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How to Make a Map | Geography for Kids | Made by Red Cat Reading

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How to Create a Scale Drawing (For your map!)

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How to Create a Scale Drawing (For your map!)

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How to Make a Scale Drawing | 7th Grade | Simplifying Math

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Renewable Power Sources Classroom Code: 2866EF

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Renewable Power Sources Classroom Code: 2866EF

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Renewable Power Sources | Kids Discover Online

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Learn About Maps - Symbols, Map Key, Compass Rose

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Maps have been a part of human culture for millenia. Whether it’s to show terrain details in preparation for invasion, plotting trade routes across oceans, or even how to get from one station to an other, maps can be used for many...

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The genius of Mendeleev's periodic table - Lou Serico

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Renewable Energy Sources - Types of Energy for Kids

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How does a solar cell work? | Ever wonder how a solar cell actually works? Check out the next video in our learning series on climate and solar energy. In today’s episode, our... | By Swift SolarFacebook

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Ever wonder how a solar cell actually works? Check out the next video in our learning series on climate and solar energy. In today’s episode, our...

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Renewable vs. nonrenewable resources | MightyOwl Science | 4th Grade

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Can 100% Renewable Energy Power the World?

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Can 100% Renewable Energy Power the World?

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Can 100% renewable energy power the world? - Federico Rosei and Renzo Rosei

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Renewable Energy 101: How Does Hydroelectricity Work?

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How do wind turbines work? - Rebecca J. Barthelmie and Sara C. Pryor

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How do solar panels work? - Richard Komp

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Sustainability of Periodic Table Natural Elements

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Sustainability of Periodic Table Natural Elements

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Sustainability table: the latest version of the periodic table. (Courtesy: European Chemical Society)

We do love an alternative periodic table here at Physics World, so I was chuffed to discover that the European Chemical Society has put a sustainable twist on its version of the table that displays the elements in terms of their abundance here on Earth

Any guesses regarding the most abundant element on Earth? Judging from the table it is oxygen, followed possibly by silicon and then maybe hydrogen. You might be wondering why I am not certain about the order. The reason, as you can see above, is that there are no numbers associated with the abundances. It is also not clear to me whether the abundances are given in terms of numbers of atoms on the planet or by mass - however, a little digging reveals that the areas are proportional to the numbers of atoms of each element on a logarithmic scale.

New in this latest version is the security of supply of the elements. This is important if they are used in key technologies such as mobile phones, which is designated in the table using an icon. Also highlighted is whether the production of an element occurs in areas of conflict.

Contentious carbon

The one element that had me scratching my head is carbon. According to the table there is a serious threat to some of the global supply of the element and that some of the global supply comes from conflict zones. According to the European Chemical Society this reflects the serious threat to the environment that the burning of carbon-based fossil fuels poses and the fact that some oil is extracted in areas of conflict.

Something I would like to see in the next version of this table is which elements are crucial to developing green technologies, and if we have enough of them.

As someone who is getting a little long in the tooth, I'm always on the lookout for stories of physicists who have scored major achievements later in life. Meet Manfred Steiner, who at the age of 89 has just completed a PhD in physics from Brown University in the US. In his youth, Steiner loved physics but put that aside to follow his family's advice and become a medical doctor. He first trained in his native Vienna before moving to the US, where he had a distinguished career in haematology before retiring in 2000.

That is when he rekindled his passion for physics and enrolled in Brown first as an undergraduate, completing his degree part time in 2007. Now he has completed his PhD with the approval of his thesis "Corrections to the geometrical interpretation of bosonization".

By the way, this is Steiner's second PhD, he had already done one in biochemistry. So, he is a doctor three times over.

"It is important not to waste your older days," says Steiner. "There is a lot of brainpower in older people and I think it can be of enormous benefit to younger generations."

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New periodic table focuses on sustainability, gaining a physics PhD age 89 - Physics World

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They Might Be Giants - Meet the Elements (official TMBG video)

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Static and Dynamic Electricity | Kids Discover Online

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What is Electricity? (CLICK WATCH ON YOUTUBE)

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What is Electricity? (CLICK WATCH ON YOUTUBE)

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In Millennium Park, Chicago children play in the water feature to escape the summer heat | Image by PPS

People often ask us, "What makes a public space great?"

When PPS was recently approached by USA Today to provide a list of the best city parks in the U.S. for their upcoming interactive webpage, we were excited for the opportunity share our thoughts on this question that has been at the core of our work for 40 years. After narrowing down our extensive library, our co-founder Kathy Madden submitted 20 parks for consideration. A handful of our selections were chosen for the shortlist (now available online for your vote)! Some of those chosen included some longtime favorites, such as Central Park in NYC, Jackson Square in New Orleans, Millennium Park in Chicago, and Boston Public Garden.

Although famous spaces like Central Park will always top lists like these, we wanted to take the opportunity to highlight some other examples of great public spaces around the world-including a few that may sometimes fly under the radar.

So, how do we decide if a public space is great? Good question, since it might seem pretty subjective-one person might feel deterred from the same place that another feels a deep attachment to. This is why we created our Place Diagram.

A successful public space generally needs to offer four qualities: it should be accessible, it should be comfortable and have a good image, people should be able to engage in an array of activities, and, it should be sociable. With these characteristics in mind, the possibilities are endless as to what type of public space can be successful, whether it's a street, waterfront, playground, market, or park.

Looking even more closely at the qualities of the Place Diagram, we've identified a few other attributes that contribute to making a public space great. While being a place to meet, a place for exchange, or a place of local or national pride, great public spaces can also be characterized by the presence of people remaining when they have no pressing reason to stay. You might call this the "lingering factor." Successful public spaces are also well-managed: this includes cleaning, offering food or services, or scheduling events, and such implementations can be managed the community, by individuals, by the city or district, or through local partnerships.

Great public spaces also serve as the heart of a community, often connecting two or more separate neighborhoods together, and encouraging a central point where people can interact and participate in the public realm. Another important but sometimes overlooked element of great public spaces is their ability to highlight an area's cultural identity - whether through local practices, location, history, design, architecture, or art. This is crucial factor for creating a sense of place that can withstand the test of time.

With these ideas in mind, we have gathered a few examples from our Great Public Spaces database that highlight each of these qualities.

Nyhavn - Copenhagen, Denmark

A mixture of activities, car-free spaces, and a strong cultural identity add to the success of Nyhavn in Copenhagen |Image by Bill Smith

Nyhavn canal has been around for a while - it was dug from 1671-1673 to allow ships access to Kongens Nytorv. Up until 1950, Nyhavn was well known for being a red light district with seedy bars, tattoo parlours, and strip clubs. Since then it has changed quite a bit, but this colorful history gives the location with a distinct cultural appeal to the still-popular location. Surrounded on both sides by a variety of brightly colored buildings, the canal is small and intimate. It is easily accessible, as everywhere in Copenhagen is within walking distance.

Since it is a canal, there are no cars getting in the way of the experience, and it is completely pedestrian and bike friendly. A strip exists on both sides of the canal filled with access to activities such as boat riding, restaurants, bars, and a range of places to sit and relax and take in this site that epitomizes Copenhagen. The tiniest ray of sunshine on the canal will draw people out to the cafes in an instant, encouraging sociability and activity. Nyhavn is quaint, aesthetically pleasing, well-managed, and oozes authenticity which makes you feel like you're actually a part of Scandinavian culture - we think it is an excellent example of a successful waterfront place.

Jemaa El-Fna - Marrakesh, Morocco

Market vendors offer their goods to locals and passersby in Jamaa-el-Fna in Marrakesh | Image by SuperCar-RoadTrip.fr

Located beneath the foothills of the Atlas Mountains in the heart of the Medina, Jemaa el-Fna has served as Marrakech's main market square since its foundation in the 11th century. Today the market bridges the old and new sections of Marrakech, and it continues to serve the community as a vibrant hub for trade, social life, and cultural expression. During portions of the 20th century the square was also used as a transport station, but since 2000 it has been closed entirely to automobile traffic. A lively source of entertainment for the local community as well as travelers, the marketplace functions as both a traditional market and an open-air stage for various musical, religious, and theatrical performances.

On one side of the square stands a traditional North African market, or souk, selling food, spices, carpets, brass and wood works, and tourist trinkets. All through the day, and well into the night, the marketplace offers an eclectic variety of services such as dental care, traditional medicine, fortune-telling, henna tattooing, and storytelling for children. The bazaar is well known for its hundreds of colorful umbrellas that shield shoppers, performers, and merchants from the harsh North African sun. As a market, theater, and public gathering place, Jemaa el-Fna is a repository of Moroccan cultural traditions both ancient and new, and we feel it is an excellent public space.

Mission Dolores Park - San Francisco, California, USA

Locals relax and take advantage of the sun and spectacular views in San Francisco's Mission Dolores Park - Image by Tim Riley

San Francisco's Mission Dolores Park, is not only situated in between two historic and culturally diverse neighborhoods - the famous Castro and Mission Districts - but it is a beautiful eight square block park nestled on a hillside with broad sweeping views of the San Francisco downtown and Bay Area skyline. The park is conveniently located only a few blocks from bustling Market Street which links to neighborhoods all over the city. Accessible by light rail, Dolores Park is also walking distance from the BART, multiple MUNI and bus lines, and the Haight Ashbury neighborhood. There are benches bordering the park and scattered throughout, but most people prefer to sit on the sloped ground which faces the spectacular views of the city.

Besides the great views, the park features opportunities for activities such as basketball, tennis, walking paths, and a playground, and it is not uncommon to see people throwing a frisbee, or dogs chasing balls. It is happily shared by families and young people at all hours of the day, and a bonus is that it's surrounded by some of the best cafes the city has to offer - it is the perfect place to bring a cup of coffee and a muffin with the morning paper. Mission Dolores Park is quintessentially California - it is placed in the pathway of sunshine, dotted with palm trees, it is often the center point for events and parties of an alternative nature, and we feel it is a great example of a local park.

Turkenmarkt (The Turkish Market) - Berlin, Germany

Berlin's bustling canalside Turkenmarkt draws a mix of people from all over the city to experience the diverse goods it has on offer | Image by Bernard Oh

Neukolln's Turkenmarkt, a streetmarket in Berlin, will make you believe you've been transported to Istanbul. Berlin has the third largest Turkish population of any city in the world, so it is no wonder that the Turkish Market is one of the city's liveliest and exciting marketplaces. This is the largest Turkish market in the city and is easily accessible, spanning along the river Landwehrkanal half a mile from Neukolln to Kreuzberg. These neighborhoods remain the center of Turkish immigrant life in Berlin, and are becoming increasingly popular due their cultural appeal. Though the market caters more to a Turkish immigrant population, it is more common now to see Turkish women in headscarves shopping alongside trendsetting artists and musician-types, all using the market as a local food source.

In addition to perhaps being the best place for fresh fruit and vegetables in Berlin, you can also find olives, herbs and spices, clothing, Turkish pizzas, unbeatable kebaps, and other delicacies. Often people settle along the river to sit, enjoy some of their purchased goods, relax, or simply wander up and down the market browsing all of the products on offer. Turkenmarkt epitomizes the cultural mix of Berlin, and the setting of this market, as well as the delicacies on offer, cannot be beat. We feel it is an excellent example of a public space - in fact, an LQC type example that shows public spaces do not have to be large, or permanent, to have a positive impact on the local community.

Luxembourg Gardens - Paris, France

Moveable chairs can be found dotted on pathways around Luxembourg Gardens in Paris | Image by Byron T.

Luxembourg Gardens came about as a result of Henri IV's assassination in 1610. His wife, Marie de Medicis, could not continue living in the Louvre with his memory. She had the Palais du Luxembourg and the surrounding gardens built to replicate her childhood home, Florence's Palazzo Pitti. The Luxembourg Gardens were completed in 1625, and the park itself has been open to the public since the 17th century. The construction of nearby streets and avenues during the Second Empire reduced its size, but not its general appearance. In the present day, this self-managed park, which closes at sunset, has a multitude of strolling paths, and is filled with hundreds of movable chairs that users take situate to their liking.

The Luxembourg Gardens may well be one of the most successful parks in the world, partly because it is so well integrated into the fabric of the city around it, which makes it easily accessible. There are also many things to do there, evidenced by the wide range of people who use it: children, older people, Sorbonne students, people cutting through on a lunch break, etc. People come to stroll, play chess, to sit and read, people watch, to sit at one of the cafes or to bring their children or grandchildren to one of the many attractions for kids. Organized activities at the park include tennis, outdoor concerts, pony rides, puppet theatres, and toy sailboat rentals, which make this public place full of endless activity, encouraging people to linger. It is one of our favorite public spaces, and it continues to be a leading example in terms of providing a mix of easy access, activities, aesthetics, and sociability.

Khan el Khalili - Cairo, Egypt

Khan El Khalili in Cairo is a market that inspires us to make the best out of urban alleyways | Image by Stephen Friday

A charming labyrinth of narrow alleys, the Khan El Khalili Bazaar, or the Khan, is a major souk in Cairo, Egypt. It is located next to two of the city's major landmarks, the Al-Hussein mosque and prestigious Al- Azhar University. Originally the burial site of the Fatimid caliphs and part of the Fatimid Great Eastern Palace, Khan El Khalili Bazaar was constructed in 970 AD, the same year as the founding of Cairo. While the bazaar's layout has been drastically modified since then, it continues to function as the city's major center of trade and a popular destination for tourists and locals in search of treasures.

The bazaar itself is an architectural draw, with monumental gates that resemble the commercial complexes of the Ottoman empire. Visitors to Khan El Khalili Bazaar will find themselves transported back in time to a traditional Arab souk, lost in the scent of spices and bustle of trade that takes place in the market daily. The many shops arranged around small courtyards stock a variety of goods from soap powder to fabrics, stones, and souvenir toy camels. While the market is not strictly organized by the types of goods, its major crowd-pullers such as gold, copper and spice are still clustered in certain sections. Khan El Khalili is an important shopping area for locals and continues to preserve the market tradition of old Cairo - we feel it is offers creative inspiration as to how urban spaces can be transformed into public treasures.

***

While these six great public spaces might be exemplary, they are just a few of thousands around the world that are worth highlighting. Such a range of unique and functional public spaces is what inspired us to create our Great Public Spaces resource -an inspiring collection of the world's treasured places that are loved by locals and visitors alike, and a collection that's growing every week.

Do you know a great public space that deserves some recognition? Nominate your favorite place to be featured on our Great Public Spaces resource! We'd love to hear from you.

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You Asked, We Answered: 6 Examples of What Makes a Great Public Space

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People often ask us, "What makes a public space great?" When PPS was recently approached by USA Today to provide a list of the best city parks in the U.S. for their upcoming interactive webpage, we were excited for the opportunity share our thoughts on this question that has been at the core of our work for 40 years.

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How do Batteries Work? (With Narration) | Mocomi Kids

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From the Power Plant to You Classroom Code: 2866EF

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From the Power Plant to You Classroom Code: 2866EF

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Electricity from the Power Plant to You | Kids Discover Online

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Bill Nye the Science Guy  0118 Electricity

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How does a battery work? - Simple and easy explanation for kids.

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Conductors And Insulators - Examples, Definition, Properties | Video for Kids

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Renewable vs. nonrenewable resources | MightyOwl Science | 4th Grade

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Have you ever wondered what happens when you flip a switch to turn on a light, TV, vacuum cleaner or computer? What does flipping that switch accomplish? In all of these cases, you are completing an electric circuit, allowing a current, or flow of electrons, through the wires.

An electric circuit is in many ways similar to your circulatory system. Your blood vessels, arteries, veins and capillaries are like the wires in a circuit. The blood vessels carry the flow of blood through your body. The wires in a circuit carry the electric current to various parts of an electrical or electronic system.

Your heart is the pump that drives the blood circulation in the body. It provides the force or pressure for blood to circulate. The blood circulating through the body supplies various organs, like your muscles, brain and digestive system. A battery or generator produces voltage -- the force that drives current through the circuit.

Take the simple case of an electric light. Two wires connect to the light. For electrons to do their job in producing light, there must be a complete circuit so they can flow through the light bulb and then back out.

The diagram above shows a simple circuit of a flashlight with a battery at one end and a flashlight bulb at the other end. When the switch is off, a complete circuit will not exist, and there will be no current. When the switch is on, there will be a complete circuit and a flow of current resulting in the flashbulb emitting light.

Circuits can be huge power systems transmitting megawatts of power over a thousand miles -- or tiny microelectronic chips containing millions of transistors. This extraordinary shrinkage of electronic circuits made desktop computers possible. The new frontier promises to be nanoelectronic circuits with device sizes in the nanometers (one-billionth of a meter).

In this article, we'll learn about the two basic types of electric circuits:

Power circuits transfer and control large amounts of electricity. Examples are power lines and residential and business wiring systems. The major components of power circuits are generators at one end and lighting systems, heating systems or household appliances at the other end. In between are power lines, transformers and circuit breakers.

Electronic circuits process and transmit information. Think computers, radios, TVs, radars and cell phones.

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Have you ever wondered what happens when you flip a switch to turn on a light, TV, vacuum cleaner or computer? What does flipping that switch accomplish? In all of these cases, you are completing an electric circuit, allowing a current, or flow of electrons, through the wires.

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This article was co-authored by Bess Ruff, MA. Bess Ruff is a Geography PhD student at Florida State University. She received her MA in Environmental Science and Management from the University of California, Santa Barbara in 2016. She has conducted survey work for marine spatial planning projects in the Caribbean and provided research support as a graduate fellow for the Sustainable Fisheries Group.

A circuit is a closed path that electrons flow along to provide power to your home and electronics. A simple electric circuit contains a power source (battery), wires, and a resistor (light bulb). In a circuit, electrons flow from the battery, through the wires, and into the light bulb. When the bulb receives enough of these electrons it will light up. When constructed properly, you will be able to light your bulb with just a few simple steps.

Building a Simple Circuit with a Battery

1. Gather the necessary materials. To build a simple circuit, you will need a power source, 2 insulated wires, a light bulb, and a light bulb holder. A power source can be any type of battery or battery pack. The rest of the materials can be found at your local hardware store.

When choosing a light bulb, find one that is around 15-25 volts so a single battery can power them.

To simplify the wire attachment process, use a battery snap with wires pre-attached and a 9-volt battery or battery pack.

2. Strip the ends of the insulated wires. In order for your circuit to work properly, the wires need to be totally exposed so you must strip the ends. Using wire strippers, remove about 1 inch (2.5 cm) of the insulation from the ends of each wire.

If you don't have wire strippers, you can carefully use scissors to cut off the insulation.

Be careful not to cut all the way through the wire.

3. Attach your wires to the battery pack. The wires will be conducting your electric current from the batteries to the light bulb. The easiest way to attach the wires is to use electrical tape. Attach the end of one wire to one side of the battery, making sure that the wire maintains contact with the metal of the battery. Repeat with the other wire on the other side of the battery.

Alternatively, if you are using a battery snap, snap the end onto the end of a 9-volt battery or the battery pack.

Use caution while building your circuit. Although unlikely, it is possible to get a very small shock if you touch the wire directly while attached to the battery. You can avoid this by only touching the insulated part of the wire or removing the batteries until you install the light bulb.

4. Test your circuit. Screw the light bulb into its holder until it is tight. If your circuit is hooked up properly, the bulb should light up when fully screwed into its socket.

Light bulbs can heat up quickly so be careful when installing and removing the bulb.

If the bulb doesn't light, check to make sure the wires are touching the ends of the battery and in contact with the metal of the screws.

Installing a Switch

Test your circuit. Screw the light bulb into its holder until it is tight. Flip the switch! If your circuit is hooked up properly, the bulb should light up when fully screwed into its socket.

Light bulbs can heat up quickly so be careful when installing and removing the bulb.

If the bulb doesn't light, check to make sure the wires are touching the ends of the battery and in contact with the metal of the screws.

Troubleshooting Your Circuit

1. Make sure all of the wires are connected properly. In order to complete the circuit, all wires must be touching the metal parts of each component. If your bulb doesn't light up, check each side of the battery and the screws on the bulb holder to make sure the wires are in contact with metal.

Make sure screws are tightened down to maintain contact.

In some cases, you may need to strip more of the insulation off the wire.

2. Test the charge of the battery. If the battery is dead or low on charge, it might not have enough power to light the bulb. Using a battery tester, check the charge or just replace the battery with a new one. If this was the problem, your bulb should light immediately after replacing the battery.

Community Q&A

Add New Question

Where can I find a battery pack?

Bess Ruff, MA
Master's Degree, Environmental Science & Management, University of California Santa Barbara

Bess Ruff is a Geography PhD student at Florida State University. She received her MA in Environmental Science and Management from the University of California, Santa Barbara in 2016. She has conducted survey work for marine spatial planning projects in the Caribbean and provided research support as a graduate fellow for the Sustainable Fisheries Group.

Master's Degree, Environmental Science & Management, University of California Santa Barbara

You should be able to purchase a battery pack at your local hardware store.

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Things You'll Need

This article was co-authored by Bess Ruff, MA. Bess Ruff is a Geography PhD student at Florida State University. She received her MA in Environmental Science and Management from the University of California, Santa Barbara in 2016. She has conducted survey work for marine spatial planning projects in the Caribbean and provided research support as a graduate fellow for the Sustainable Fisheries Group.

To make a simple electrical circuit with a battery, use wire strippers or scissors to strip the ends of a length of insulated wire, but do not cut all the way through the wire. Install your batteries in a battery pack, then attach your wires to the battery pack using a battery snap or electrical tape. Fasten the other end of the wire to the metal screw of the bulb holder. Screw the bulb tightly into the holder. If the circuit is properly connected, the bulb should light up! Keep reading to learn how to install a switch on your circuit!

Thanks to all authors for creating a page that has been read 634,155 times.

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This article was co-authored by Bess Ruff, MA. Bess Ruff is a Geography PhD student at Florida State University. She received her MA in Environmental Science and Management from the University of California, Santa Barbara in 2016. She has conducted survey work for marine spatial planning projects in the Caribbean and provided research support as a graduate fellow for the Sustainable Fisheries Group.

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Water, Wind, and Other Sources of Energy | Kids Discover Online

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Nuclear, Solar, Geothermal Classroom Code: 2866EF

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Nuclear, Solar, Geothermal Classroom Code: 2866EF

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Nuclear, Solar, and Geothermal Energy | Kids Discover Online

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The Parts of an Atom Classroom Code: 2866EF

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The Parts of an Atom Classroom Code: 2866EF

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The Parts of an Atom | Kids Discover Online

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“Atom.” The word comes from the Greek a-tomos, meaning “indivisible.” At the time these particles were named, scientists thought atoms were the smallest bits of stuff found in nature. We now know differently, but the name stuck.

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Are you thinking about adding solar to your home? With over 2 million homes in the United States with solar now, many homeowners are recognizing how beneficial they are. If you're considering having solar panels installed in your home and not sure where to start, then you've come to the right place.

We're going to go over the details of how solar panels work and how many you might need for your home.

Let's take a look.

How Do Solar Panels Work?

Simply put, solar panels absorb photons that then tap electrons free. Once they're free from the atoms, it creates electricity! Solar panels take in light and directly turns it into a flow of electricity to use.

Solar panel cells absorb sunlight

They convert the light into DC power.

All systems need some type of inverter (string, Micro or hybrid) to convert that power to AC power.

The electricity is then sent through wires into your home

That powers everything connected to it

Any excess of electricity produced is then fed into the electric grid

Solar systems are not complicated and easy to understand once you have the basics down. Now that you understand how they work, let's take a look at how long they last -

How Long Do Solar Panels Last?

In short, a quality solar panel can last up to 25 years or even longer. Solar panels are designed to live a long life in the elements outside.

Your typical solar panels come with a warranty that lasts 25 years, so you are guaranteed to reap the benefits for quite a long time.

According to a study conducted by the National Renewable Energy Laboratory, solar panels last 80% longer than their warranty.

This can save you thousands on utility bills down the road!

How many Solar Panels Do You Need?

To find out how many solar panels you'll need for your home, you need to consider everything that uses power. Taking a look at your utility bill can also give you a good idea of how many you might need.

How Many Watts Do You Use?

When looking at your utility bill, you should be able to see kilowatt-hours (KWH). KWH for homes can vary greatly depending on location. A home in the south is more likely to draw massive amounts of energy from air conditioner units.

Finding the average daily energy usage will help you calculate your solar needs. Once you have your usage you can look at how much wattage you'll need to be able to run everything.

Peak Sunlight Hours

Keep in mind that solar panels only work when they are in direct sunlight. After the sun is no longer shining down on them, they aren't producing energy. Peak sunlight hours are when your panels are in direct sunlight.

Depending on your location, your peak sunlight hours can vary.

Multiply your home's hourly energy usage by the peak sunlight hours your home has and then divide that by a solar panel's wattage. You can do this both high and low wattage panels to find a range of what you might need.

Most reputable solar companies can also help you determine this by providing them with this basic information as well!

Solar Panels For a 1500 Square Foot House

The average home in the United States is roughly 1500 square feet. With a home of this size, the typical electric bill comes in around $100 month. In order to cover the electricity for this home, you would need an estimated 15-18 solar panels.

For example, a typical fridge may be rated for 250 watts and runs for 4 hours a day. 250 watts X 4 = 1000W. A 1k watt is equal to 1 kWh of energy in a day.

This, of course, is a general estimate and eclectic usage, sunlight hours, location, and the type of panels can change this amount.

Types of Solar Panel Systems

When it comes to solar panel systems, there are three different types. Gid-tied, grid-tied with battery backup, and off-grid. Let's take a look at each one.

Grid-Tied System

The most popular type of system used by residential houses is the grid-tied system. This type of system is tired directly to your home and the utility grid. This allows homeowners to seamless switch between power from either the solar system or the utility system.

If the system produces more power then the house needs, the excess power will be sold back to the utility company or it will be used to prorate your bill.

These are generally the cheaper systems out of the three.

Grid-Tied With Battery Backup

Similar to the grid-tied system, this solar power system is also connected to both your house and the utility grid. However, it also comes equipped with a battery bank.

When the panels produce electricity while in direct sun, it stores any excess power in its battery banks. This power can then be used at a later time after the sun has gone down and the panels are no longer producing power.

The power can also be sold back to the utility companies as well - This system is much more expensive though because of the expensive price of batteries.

Off-Grid System

Unlike the other two, the off-grid system is not connected to the utility grid at all. This system is only connected to your home and a battery bank. The battery bank is essential in this setup in order to continue producing power for your home 24 hours a day.

This tends to be the most expensive system because you need an excessive amount of battery in order to store the amount of energy your house will need.

How Much Do Solar Panels Cost?

Solar energy has become cost-effective most recently. The prices have gone down and they are much more available to the public. The average cost of a solar panel is almost less then half it was a decade ago.

A typical solar panel can run between 50 cents to 70 cents per watt. At 50 cents a watt, a 350W panel would cost $175. In a typical home needing 15 solar panels, the total cost for panels would be $2,625.

That is for the panels alone though, the cost of installation needs to be considered as well. It takes professional that know what they are doing to properly install a solar system in your home.

How Much Does a Solar Installation Cost?

This can vary depending on the company, but for an average installation, it can run you between $15,000 and $30,000.

Many solar companies offer incentives and financing. There are a ton of other financial benefits that come along with installing your home:

Electricity rates have risen across the nation and are higher now than they have ever been

You can save thousands on electricity bills and will only continue to save more over time

The resale value of your home skyrockets. Many home buyers now are searching for homes that come with a solar system already installed

The government offers a massive tax credit when it comes to solar systems. Some states also offer a rebate program

The systems come with a warranty that secures your investment for at least 25 years

How Much Does it Cost Total For a 1500 Square Foot House?

The typical 1500 square foot house can use around a 6kw solar panel system. The total cost of the panels and full installation can be estimated at about $18000.

To get an estimate for your home and how much you can save, contact a local energy consultant. They can provide you with an installation quote and answer any questions you have about solar systems for your home.

Things to Keep In Mind

Solar panels are a great way to save money and go green. However, they only work effectively when using the correct products and proper installation.

You want to make sure to only use quality solar panels and solar equipment. Using cheap or knock-off brands won't produce as much as quality products.

Ensuring proper installation is key to a solar system. Not having it properly installed can cause ineffective panels, failure, or fires. Make sure to always have a Professional company conduct the install for your home.

Wrapping Up

Now that you have an in-depth understanding of how solar panels work and how many you're going to need, Its time to go green and start saving money. Contact a professional solar company and receive a quote to have your solar system installed for your home.

If you have further questions about solar panels or are ready to get them installed for your home, send us a message today.

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How Many Solar Panels Are Needed to Run a House? (The Answer Will Surprise You!) - EFS Energy

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EFS Energy are Illinois and Missouri Solar Energy Experts

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If you have enough wind resource in your area and the situation is right, small wind electric systems are one of the most cost-effective home-based renewable energy systems -- with zero emissions and pollution.

Small wind electric systems can:

Lower your electricity bills by 50%-90%

Help you avoid the high costs of having utility power lines extended to a remote location

Help uninterruptible power supplies ride through extended utility outages.

Small wind electric systems can also be used for a variety of other applications, including water pumping on farms and ranches.

Our pages on planning for a small wind electric system, and on installing and maintaining a small wind electric system have more information.

How a Small Wind Electric System Works

Wind is created by the unequal heating of Earth's surface by the sun. Wind turbines convert the kinetic energy in wind into clean electricity. When the wind spins the wind turbine's blades, a rotor captures the kinetic energy of the wind and converts it into rotary motion to drive the generator. Our wind power animation has more information about how wind systems work and the benefits they provide.

A small wind system can be connected to the electric grid through your power provider or it can stand alone (off-grid). This makes small wind electric systems a good choice for rural areas that are not already connected to the electric grid.

Small Wind Electric System Components

A wind electric system is made up of a wind turbine mounted on a tower to provide better access to stronger winds. In addition to the turbine and tower, small wind electric systems also require balance-of-system components.

Turbines

Most small wind turbines manufactured today are horizontal-axis, upwind machines that have two or three blades. These blades are usually made of a composite material, such as fiberglass.

The turbine's frame is the structure onto which the rotor, generator, and tail are attached. The amount of energy a turbine will produce is determined primarily by the diameter of its rotor. The diameter of the rotor defines its "swept area," or the quantity of wind intercepted by the turbine. The tail keeps the turbine facing into the wind.

Towers

Because wind speeds increase with height, a small wind turbine is mounted on a tower. In general, the higher the tower, the more power the wind system can produce.

Most turbine manufacturers provide wind energy system packages that include towers. There are two basic types of towers: self-supporting (free-standing) and guyed (supported with wires). There are also tilt-down versions of each tower type.

While tilt-down towers are more expensive, they offer an easy way to perform maintenance. Tilt-down towers can also be lowered to the ground during hazardous weather such as hurricanes.

Balance of System Components

The balance-of-system parts you'll need for a small wind electric system -- those in addition to the wind turbine and the tower -- will depend on your application. For example, the parts required for a water pumping system will be much different from what you need for a residential application.

The balance-of-system parts required will also depend on whether your system is grid-connected, stand-alone, or hybrid.

Manufacturers and installers can provide you with a system package that includes all the parts you need for your particular application. For a residential grid-connected application, the balance-of-system parts may include the following:

A controller

Storage batteries

An inverter (power conditioning unit)

Wiring

Electrical disconnect switch

Grounding system

Foundation for the tower.

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If you have enough wind resource in your area and the situation is right, small wind electric systems are one of the most cost-effective home-based renewable energy systems -- with zero emissions and pollution.

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Run-of-the-river microhydropower systems consist of these basic components:

Water conveyance -- channel, pipeline, or pressurized pipeline (penstock) that delivers the water

Turbine, pump, or waterwheel -- transforms the energy of flowing water into rotational energy

Alternator or generator -- transforms the rotational energy into electricity

Regulator -- controls the generator

Wiring -- delivers the electricity.

Commercially available turbines and generators are usually sold as a package. Do-it-yourself systems require careful matching of a generator with the turbine horsepower and speed.

Many systems also use an inverter to convert the low-voltage direct current (DC) electricity produced by the system into 120 or 240 volts of alternating current (AC) electricity. (Alternatively, you can buy household appliances that run on DC electricity.)

Whether a microhydropower system will be grid-connected or stand-alone will determine many of its balance of system components.

For example, some stand-alone systems use batteries to store the electricity generated by the system. However, because hydropower resources tend to be more seasonal in nature than wind or solar resources, batteries may not always be practical for microhydropower systems. If you do use batteries, they should be located as close to the turbine as possible because it is difficult to transmit low-voltage power over long distances.

Impulse turbines, which have the least complex design, are most commonly used for high-head microhydro systems. They rely on the velocity of water to move the turbine wheel, which is called the runner. The most common types of impulse turbines include the Pelton wheel and the Turgo wheel.

Pelton wheel -- uses the concept of jet force to create energy. Water is funneled into a pressurized pipeline with a narrow nozzle at one end. The water sprays out of the nozzle in a jet, striking the double-cupped buckets attached to the wheel. The impact of the jet spray on the curved buckets creates a force that rotates the wheel at high efficiency rates of 70-90%. Pelton wheel turbines are available in various sizes and operate best under low-flow and high-head conditions.

Turgo impulse wheel -- an upgraded version of the Pelton. It uses the same jet spray concept, but the Turgo jet, which is half the size of the Pelton, is angled so that the spray hits three buckets at once. As a result, the Turgo wheel moves twice as fast. It's also less bulky, needs few or no gears, and has a good reputation for trouble-free operations. The Turgo can operate under low-flow conditions but requires a medium or high head.

Jack Rabbit turbine -- a drop-in-the-creek turbine that can generate power from a stream with as little as 13 inches of water and no head. Output from the Jack Rabbit is a maximum of 100 Watts, so daily output averages 1.5-2.4 kilowatt-hours, depending on your site. Sometimes referred to as the Aquair UW Submersible Hydro Generator.

Reaction turbines, which are highly efficient, depend on pressure rather than velocity to produce energy. All blades of the reaction turbine maintain constant contact with the water. These turbines are often used in large-scale hydropower sites.

Because of their complexity and high cost, reaction turbines aren't usually used for microhydropower projects. An exception is the propeller turbine, which comes in many different designs and works much like a boat's propeller.

Propeller turbines have three to six usually fixed blades set at different angles aligned on the runner. The bulb, tubular, and Kaplan tubular are variations of the propeller turbine. The Kaplan turbine, which is a highly adaptable propeller system, can be used for microhydro sites.

Conventional pumps can be used as substitutes for hydraulic turbines. When the action of a pump is reversed, it operates like a turbine. Since pumps are mass produced, you'll find them more readily than turbines. Pumps are also less expensive. For adequate pump performance, however, your microhydropower site must have fairly constant head and flow. Pumps are also less efficient and more prone to damage.

The waterwheel is the oldest hydropower system component. Waterwheels are still available, but they aren't very practical for generating electricity because of their slow speed and bulky structure.

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Run-of-the-river microhydropower systems consist of these basic components: Water conveyance -- channel, pipeline, or pressurized pipeline (penstock) that delivers the water Turbine, pump, or waterwheel -- transforms the energy of flowing water into rotational energy Alternator or generator -- transforms the rotational energy into electricity Regulator -- controls the generator Wiring -- delivers the electricity.

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Hydropower is energy in moving water

People have a long history of using the force of water flowing in streams and rivers to produce mechanical energy. Hydropower was one of the first sources of energy used for electricity generation and is usually the largest single renewable energy source of annual electricity generation in the United States.

n 2022, hydroelectricity accounted for about 6.2% of total U.S. utility-scale electricity generation and 28.7% of total utility-scale renewable electricity generation. ¹ Hydroelectricity generation varies annually, and it's share of total U.S. electricity generation generally decreased from the 1950's through 2020, mainly because of increases in electricity generation from other sources. Hydroelectricity's percentage share of total annual U.S. electricity generation in 2001 through 2022 averaged about 6.7%.

Hydropower relies on the water cycle

1. Solar energy heats water on the surface of rivers, lakes, and oceans, which causes the water to evaporate.

2. Water vapor condenses into clouds and falls as precipitation-rain and snow.

3. Precipitation collects in streams and rivers, which empty into oceans and lakes, where it evaporates and begins the cycle again.

The amount of precipitation that drains into rivers and streams in a geographic area determines the amount of water available for producing hydropower. Seasonal and long-term changes in rain and snowfall, such as droughts, have a big effect on hydropower production.

Hydroelectric power is produced with moving water

Because the source of hydroelectric power is water, hydroelectric power plants are usually located on or near a water source. The volume of the water flow and the change in elevation (or fall) from one point to another determine the amount of available energy in moving water. In general, the greater the water flow and the higher the fall, the more electricity a hydropower plant can produce. A big river, such as the Columbia River that forms the border between Oregon and Washington, carries a great deal of energy in its flow. Water descending rapidly from a high point, such as Niagara Falls in New York, also has substantial energy in its flow.

At hydropower plants, water flows through a pipe, or penstock, then pushes against and turns blades in a turbine to spin a generator to produce electricity.

Conventional hydroelectric facilities include

Run-of-the-river systems, where the force of the river's current applies pressure on a turbine. The facilities may have a weir (a short or low dam) in the water course to divert water flow to hydro turbines.

Storage systems, where water accumulates in reservoirs created by dams on streams and rivers and is released through hydro turbines as needed to generate electricity. Most U.S. hydropower facilities have dams and storage reservoirs.

Pumped-storage hydropower facilities are a type of hydroelectric storage system where water is pumped from a water source up to a storage reservoir at a higher elevation and is released from the upper reservoir to power hydro turbines located below the upper reservoir. The electricity for pumping may be from hydroturbines or from other types of power plants including fossil fuel or nuclear power plants. They usually pump water to storage when electricity demand (or use) and prices are low and release the stored water to generate electricity when electricity demand and prices are higher. Pumped-storage hydroelectric systems generally use more electricity to pump water to the upper water storage reservoirs than they produce with the stored water.

History of hydropower

Hydropower is one of the oldest sources of energy for producing mechanical and electrical energy. Hydropower was used thousands of years ago to turn paddle wheels to help grind grain. Before steam power and electricity were available in the United States, grain and lumber mills were powered directly with hydropower. The first industrial use of hydropower to generate electricity in the United States was in 1880, when 16 brush-arc lamps were powered using a water turbine at the Wolverine Chair Factory in Grand Rapids, Michigan. The first U.S. hydroelectric power plant opened on the Fox River near Appleton, Wisconsin, on September 30, 1882. Most U.S. hydroelectricity is now produced at large dams on major rivers, and most of these hydroelectric dams were built before the mid-1970s.

Most U.S. hydroelectricity generation capacity is in the West

There are hydropower facilities in nearly every state. Most hydroelectricity is produced at large dams built by the federal government, and many of the largest hydropower dams are in the western United States.

About half of U.S. hydroelectricity generation capacity ² is in Washington, California, and Oregon. Washington has the most hydroelectric generating capacity of any state and is the site of the Grand Coulee Dam, the largest hydropower facility in the United States. New York has the largest hydroelectricity generation capacity of all states east of the Mississippi River, followed by Alabama.

In 2022, total U.S. conventional hydroelectricity net summer electricity generation capacity 79,980 megawatts (MW)-or about 80 million kilowatts.

Hydroelectricity generation varies with precipitation levels

Because hydroelectricity generation depends on precipitation, and precipitation levels vary seasonally and annually, the ranking of each state in annual hydroelectricity generation may be different from its ranking in generation capacity.

In 2022, total U.S. conventional hydroelectricity generation was equal to about 6.2% (about 262 billion kilowatthours [kWh]) of total U.S. utility-scale electricity generation

Most dams were not built for electricity generation

Only a small percentage of the dams in the United States produce electricity. Most dams were constructed for irrigation and flood control and do not have hydroelectricity generators. The U.S. Department of Energy estimated that in 2012, non-powered dams in the United States had a total of 12,000 megawatts (MW) of potential hydropower capacity.

Hydropower generators produce clean electricity, but hydropower does affect the environment

Most dams in the United States were built mainly for flood control, municipal water supply, and irrigation water. Although many of these dams have hydroelectric generators, only a small number of dams were built specifically for hydropower generation. Hydropower generators do not directly emit air pollutants. However, dams, reservoirs, and the operation of hydroelectric generators can affect the environment.

Did you know?

A dam that creates a reservoir (or a dam that diverts water to a run-of-river hydropower plant) may obstruct fish migration. A dam and reservoir can also change natural water temperatures, water chemistry, river flow characteristics, and silt loads. All of these changes can affect the ecology and the physical characteristics of the river. These changes may have negative effects on native plants and on animals in and around the river. Reservoirs may cover important natural areas, agricultural land, or archeological sites. A reservoir and the operation of the dam may also result in the relocation of people. The physical impacts of a dam and reservoir, the operation of the dam, and the use of the water can change the environment over a much larger area than the area a reservoir covers.

Manufacturing the concrete and steel in hydropower dams requires equipment that may produce emissions. If fossil fuels are the energy sources for making these materials, then the emissions from the equipment could be associated with the electricity that hydropower facilities generate. However, given the long operating lifetime of a hydropower plant (50 years to 100 years) these emissions are offset by the emissions-free hydroelectricity.

Greenhouse gases (GHG) such as carbon dioxide and methane form in natural aquatic systems and in human-made water storage reservoirs as a result of the aerobic and anaerobic decomposition of biomass in the water. The exact amounts of GHG that form in and are emitted from hydropower reservoirs is uncertain and depend on many site specific and regional factors.

Fish ladders help salmon reach their spawning grounds

Hydropower turbines kill and injure some of the fish that pass through the turbine. The U.S. Department of Energy has sponsored the research and development of hydroturbines that could reduce fish deaths to lower than 2%, in comparison with fish kills of 5% to 10% for the best existing turbines.

Many species of fish, such as salmon and shad, swim up rivers and streams from the sea to reproduce in their spawning grounds in the beds of rivers and streams. Dams can block their way. Different approaches to fixing this problem include the construction of fish ladders and elevators that help fish move around or over dams to the spawning grounds upstream.

The gravitational pull of the moon and sun along with the rotation of the earth cause the tides. In some places, tides cause water levels near the shore to vary up to 40 feet. People in Europe harnessed this movement of water to operate grain mills more than a 1,000 years ago. Today, tidal energy systems generate electricity. Producing tidal energy economically requires a tidal range of at least 10 feet.

Tidal barrages

One type of tidal energy system uses a structure similar to a dam called a barrage. The barrage is installed across an inlet of an ocean bay or lagoon that forms a tidal basin. Sluice gates on the barrage control water levels and flow rates to allow the tidal basin to fill on the incoming high tides and to empty through an electricity turbine system on the outgoing ebb tide. A two-way tidal power system generates electricity from both the incoming and outgoing tides.

A potential disadvantage of tidal power is the effect a tidal station can have on plants and animals in estuaries of the tidal basin. Tidal barrages can change the tidal level in the basin and increase turbidity (the amount of matter in suspension in the water). They can also affect navigation and recreation.

Several tidal power barrages operate around the world. The Sihwa Lake Tidal Power Station in South Korea has the largest electricity generation capacity at 254 megawatts (MW). The oldest and second-largest operating tidal power plant is in La Rance, France, with 240 MW of electricity generation capacity. The next largest tidal power plant is in Annapolis Royal in Nova Scotia, Canada, with 20 MW of electricity generation capacity. China, Russia, and South Korea all have smaller tidal power plants.

The United States does not have any tidal power plants, and it only has a few sites where tidal energy could be economical to produce. France, England, Canada, and Russia have much more potential to use tidal power.

Tidal turbines

Tidal turbines look similar to wind turbines. They can be placed on the sea floor where there is strong tidal flow. Because water is about 800 times denser than air, tidal turbines have to be much sturdier and heavier than wind turbines. Tidal turbines are more expensive to build than wind turbines but capture more energy with the same size blades. A demonstration tidal turbine project is under development in the East River of New York.

Tidal fences

A tidal fence is a type of tidal power system that has vertical axis turbines mounted in a fence or row placed on the sea bed, similar to tidal turbines. Water passing through the turbines generates electricity. As of the end of 2021, no tidal fence projects were operating.

Waves have a lot of energy

CETO underwater wave energy device

Waves form as wind blows over the surface of open water in oceans and lakes. Ocean waves contain tremendous energy. The theoretical annual energy potential of waves off the coasts of the United States is estimated to be as much as 2.64 trillion kilowatthours, which is equal to about 64% of total U.S. utility-scale electricity generation in 2021. ( Utility-scale generation is from electric generators/power plants with at least one megawatt of generation capacity.) The west coasts of the United States and Europe, and the coasts of Japan and New Zealand, have potential sites for harnessing wave energy. Many different methods and technologies for capturing and converting wave energy to electricity are under development. These methods include placing devices on or just below the surface of the water and anchoring devices to the ocean floor.

Different ways to channel the power of waves

One way to harness wave energy is to bend or focus waves into a narrow channel to increase their size and power and to spin the turbines that generate electricity. Waves can also be channeled into a catch basin or reservoir where the water flows to a turbine at a lower elevation, similar to the way a hydropower dam operates.

The U.S. Department of Energy's Marine and Hydrokinetic Technology Database provides information on marine and hydrokinetic renewable energy, in the United States and around the world.

Ocean thermal energy conversion produces energy from temperature differences in ocean waters

Ocean thermal energy conversion (OTEC) is a process or technology for producing energy by harnessing the temperature differences (thermal gradients) between ocean surface waters and deep ocean waters.

Energy from the sun heats the surface water of the ocean. In tropical regions, surface water can be much warmer than deep water. This temperature difference can be used to produce electricity and to desalinate ocean water. Ocean Thermal Energy Conversion (OTEC) systems use a temperature difference (of at least 36° Fahrenheit or 20° Celsius) to power a turbine to produce electricity. Warm surface water is pumped through an evaporator containing a working fluid. The vaporized fluid drives a turbine/generator. The vaporized fluid is turned back to a liquid in a condenser cooled with cold ocean water pumped from deeper in the ocean. OTEC systems using seawater as the working fluid can use the condensed water to produce desalinated water.

The United States became involved in OTEC research in 1974 with the establishment of the Natural Energy Laboratory of Hawaii Authority. The laboratory is one of the world's leading test facilities for OTEC technology. The laboratory operated a 250 kilowatt (kW) demonstration OTEC plant for six years in the 1990s. The United States Navy supported the development of a 105 kW demonstration OTEC plant at the laboratory site. This facility became operational in 2015 and supplies electricity to the local electricity grid.

Other larger OTEC systems are in development or planned in several countries, mostly to supply electricity and desalinated water for island communities.

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People have a long history of using the force of water flowing in streams and rivers to produce mechanical energy. Hydropower was one of the first sources of energy used for electricity generation and is usually the largest single renewable energy source of annual electricity generation in the United States.

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Energy from the sun

The sun has produced energy for billions of years and is the ultimate source for all of the energy sources and fuels that we use today. People have used the sun's rays (solar radiation) for thousands of years for warmth and to dry meat, fruit, and grains. Over time, people developed technologies to collect solar energy for heat and to convert it into electricity.

Collecting and using solar thermal (heat) energy

An example of an early solar energy collection device is the solar oven (a box for collecting and absorbing sunlight). In the 1830s, British astronomer John Herschel used a solar oven to cook food during an expedition to Africa. People now use many different technologies for collecting and converting solar radiation into heat energy for a many uses.

Water for use in homes, buildings, or swimming pools

The inside of homes, greenhouses, and other buildings

Fluids to high temperatures in solar thermal power plants

Solar photovoltaic systems convert sunlight into electricity

Solar photovoltaic (PV) devices, or solar cells, change sunlight directly into electricity. Small PV cells can power calculators, watches, and other small electronic devices. Arrangements of many solar cells in PV panels and arrangements of multiple PV panels in PV arrays can produce electricity for an entire house. Some PV power plants have large arrays that cover many acres to produce electricity for thousands of homes.

Solar energy has benefits and some limitations

Solar energy systems do not produce air pollutants or carbon dioxide.

Solar energy systems on buildings have minimal effects on the environment.

The amount of sunlight that arrives at the earth's surface is not constant. The amount of sunlight varies depending on location, time of day, season of the year, and weather conditions.

The amount of sunlight reaching a square foot of the earth's surface is relatively small, so a large surface area is necessary to absorb or collect a useful amount of energy.

Solar energy is sunshine

Sunshine is radiant energy from the sun. The amount of solar radiation, or solar energy, that the earth receives each day is many times greater than the total amount of all energy that people consume each day. Use of solar energy, especially for electricity generation, has increased a lot in the United States and around the world in the past 30 years.

Latitude, climate, and weather patterns are major factors that affect insolation -the amount of solar radiation received on a given surface area during a specific amount of time. Locations nearer the equator and in arid climates generally receive higher amounts of insolation than other locations. Clouds, dust, volcanic ash, and pollution in the atmosphere affect insolation levels at the surface. Buildings, trees, and mountains may shade a location during different times of the day in different months of the year. Seasonal (monthly) variations in solar resources increase with increasing distance from the earth's equator.

The type of solar collector also determines the type of solar radiation and level of insolation that a solar collector receives. Concentrating solar collector systems, such as those used in solar thermal-electric power plants, require direct solar radiation, which is generally greater in arid regions with few cloudy days. Flat-plate solar thermal and photovoltaic (PV) collectors are able to use global solar radiation, which includes diffuse (scattered) and direct solar radiation. Learn more about solar radiation.

Solar thermal collectors

Low-temperature solar thermal collectors absorb the sun's heat energy to heat water for washing and bathing or for swimming pools, or to heat air inside buildings.

Concentrating collectors

Concentrating solar energy technologies use mirrors to reflect and concentrate sunlight onto receivers that absorb solar energy and convert it to heat. We can use this thermal energy for heating buildings or to produce electricity with a steam turbine or a heat engine that drives a generator.

Photovoltaic systems

Photovoltaic (PV) cells convert sunlight directly into electricity. PV systems can range from systems that provide tiny amounts of electricity for watches and calculators to systems that provide the amount of electricity that hundreds or thousands of homes use. Millions of houses and buildings around the world have PV systems on their roofs and there are many large PV power plants.

Use of solar energy

The U.S. Energy Information Administration (EIA) estimates that total solar energy use in the United States increased from about 0.06 trillion British thermal units (Btu) in 1984 to about 1,870 trillion Btu in 2022. Solar electricity generation accounted for about 97% of total solar energy use in 2022 and direct use of solar energy for space and water heating accounted for about 3%.

Total U.S. solar electricity generation increased from about 5 million kWh in 1984 (nearly all from utility-scale, solar thermal-electric power plants) to about 204 billion kWh in 2022. In 2022, utility-scale PV power plants accounted for 70% of total solar electricity generation, small-scale PV systems accounted for 29%, and utility-scale solar thermal-electric power plants accounted for 1%. Utility-scale power plants have at least 1,000 kilowatts (kW) (or one megawatt [MW]) of electricity generation capacity. Small-scale PV systems have less than one MW generation capacity.

According to EIA's International Energy Statistics, total world solar electricity generation grew from 0.4 billion kWh in 1990 to about 1.306 billion (about 1.3 trillion) kWh in 2021. The top five producers of solar electricity and their percentage shares of world total solar electricity generation in 2021 were:

Photovoltaic cells convert sunlight into electricity

A photovoltaic (PV) cell, commonly called a solar cell, is a nonmechanical device that converts sunlight directly into electricity. Some PV cells can convert artificial light into electricity.

Photons carry solar energy

Sunlight is composed of photons, or particles of solar energy. These photons contain varying amounts of energy that correspond to the different wavelengths of the solar spectrum.

A PV cell is made of semiconductor material. When photons strike a PV cell, they may reflect off the cell, pass through the cell, or be absorbed by the semiconductor material. Only the absorbed photons provide energy to generate electricity. When the semiconductor material absorbs enough sunlight (solar energy), electrons are dislodged from the material's atoms. Special treatment of the material surface during manufacturing makes the front surface of the cell more receptive to the dislodged, or free, electrons so that the electrons naturally migrate to the surface of the cell.

The flow of electricity

The movement of electrons, each carrying a negative charge, toward the front surface of the cell creates an imbalance of electrical charge between the cell's front and back surfaces. This imbalance, in turn, creates a voltage potential like the negative and positive terminals of a battery. Electrical conductors on the cell absorb the electrons. When the conductors are connected in an electrical circuit to an external load, such as a battery, electricity flows in the circuit.

The efficiency of photovoltaic systems varies by the type of photovoltaic technology

The efficiency at which PV cells convert sunlight to electricity varies by the type of cell material and technology. The efficiency of PV modules averaged less than 10% in the mid-1980s, increased to around 15% by 2015, and is now approaching 20% for state-of-the art modules. Experimental PV cells and PV cells for space satellites are nearly 50% efficient.

How photovoltaic systems operate

The PV cell is the basic building block of a PV system. Individual cells can vary in size from about 0.5 inches to about 4 inches across. However, one cell only produces 1 or 2 Watts, which is only enough electricity for small uses, such as for powering calculators or wristwatches.

PV cells are electrically connected in a packaged, weather-tight PV module or panel. PV modules vary in size and in the amount of electricity they can produce. PV module electricity generating capacity increases with the number of cells in the module or in the surface area of the module. PV modules can be connected in groups to form a PV array. A PV array can be composed of two or hundreds of PV modules. The number of PV modules connected in a PV array determines the total amount of electricity the array can generate.

Photovoltaic cells generate direct current (DC) electricity. This DC electricity can be used to charge batteries that, in turn, power devices that use direct current electricity. Nearly all electricity is supplied as alternating current (AC) in electric power lines. Devices called inverters are used on PV modules or in arrays to convert the DC electricity to AC electricity.

PV cells and modules will produce the largest amount of electricity when they are directly facing the sun. PV modules and arrays can use tracking systems that move the modules to constantly face the sun, but these systems are expensive and are mostly used in large PV power plants. Most PV systems on buildings have modules in a fixed position with the modules facing directly south (in the northern hemisphere-directly north in the southern hemisphere). Learn more about PV collector tilt angles and PV collector tracking systems.

Did you know?

Applications of photovoltaic systems

The smallest photovoltaic systems power calculators and wristwatches. Larger systems can provide electricity to pump water, to power communications equipment, to supply electricity for a single home or business, or to form large arrays that supply electricity to thousands of electricity consumers.

PV systems can supply electricity in locations where electricity distribution systems (power lines) do not exist, and they can also supply electricity to an electric power grid.

PV arrays can be installed quickly and can be any size.

The environmental effects of PV systems located on buildings is minimal.

History of photovoltaics

The first practical PV cell was developed in 1954 by Bell Telephone researchers. Beginning in the late 1950s, PV cells were used to power U.S. space satellites. By the late 1970s, PV panels were providing electricity in remote, or off-grid, locations that did not have electric power lines. Since 2004, most of the PV panels installed in the United States have been in grid-connected systems on homes, buildings, and central-station power facilities. Technical advances, lower costs for PV systems, and financial incentives and government policies have helped to greatly expand PV use since the mid-1990s. Hundreds of thousands of grid-connected PV systems are now installed in the United States.

EIA estimates that electricity generated at utility-scale PV power plants increased from 6 million kilowatthours (kWh) in 2004 to 143 billion kWh in 2022. Utility-scale power plants have at least 1,000 kilowatts (or one megawatt) of electricity generating capacity. EIA estimates that 59 billion kWh were generated by small-scale grid-connected PV systems in 2022, up from 11 billion kWh in 2014. Small-scale PV systems are systems that have less than 1,000 kilowatts of electricity generation capacity. Most small-scale PV systems are located on buildings and are sometimes called rooftop PV systems.

Solar thermal power systems use concentrated solar energy

Solar thermal power (electricity) generation systems collect and concentrate sunlight to produce the high temperature heat needed to generate electricity. All solar thermal power systems have solar energy collectors with two main components: reflectors (mirrors) that capture and focus sunlight onto a receiver. In most types of systems, a heat-transfer fluid is heated and circulated in the receiver and used to produce steam. The steam is converted into mechanical energy in a turbine, which powers a generator to produce electricity. Solar thermal power systems have tracking systems that keep sunlight focused onto the receiver during the day as the sun changes position in the sky.

Solar thermal power systems may also have a thermal energy storage system component that allows the solar collector system to heat an energy storage system during the day, and the heat from the storage system is used to produce electricity in the evening or during cloudy weather. Solar thermal power plants may also be hybrid systems that use other fuels (usually natural gas) to supplement energy from the sun during periods of low solar radiation.

Types of concentrating solar thermal power plants

Linear concentrating systems

Linear concentrating systems collect the sun's energy using long, rectangular, curved (U-shaped) mirrors. The mirrors focus sunlight onto receivers (tubes) that run the length of the mirrors. The concentrated sunlight heats a fluid flowing through the tubes. The fluid is sent to a heat exchanger to boil water in a conventional steam-turbine generator to produce electricity. There are two major types of linear concentrator systems: parabolic trough systems, where receiver tubes are positioned along the focal line of each parabolic mirror, and linear Fresnel reflector systems, where one receiver tube is above several mirrors to allow the mirrors greater mobility in tracking the sun.

A linear concentrating collector power plant has a large number, or field, of collectors in parallel rows with a north-south orientation so that the mirrors track the sun from east to west and concentrate sunlight continuously onto the receiver tubes during the day.

Parabolic troughs

Parabolic trough power plant

A parabolic trough collector has a long parabolic (curved-shaped) reflector that focuses the sun's rays on a receiver pipe located at the focus of the parabola. The collector moves to focus sunlight on the receiver as the sun moves through the sky during the day.

Because of its parabolic shape, a trough can focus the sunlight from 30 times to 100 times its normal intensity (concentration ratio) on the receiver pipe, located along the focal line of the trough, achieving operating temperatures higher than 750°F.

Parabolic trough linear concentrating systems are used in one of the longest operating solar thermal power facilities in the world, the Solar Energy Generating System (SEGS) located in the Mojave Desert in California. The facility has had nine separate plants over time, with the first plant in the system, SEGS I, operating from 1984 to 2015, and the second, SEGS II, operating from 1985 to 2015. SEGS III-VII (3-7), each with net summer electric generation capacities of 36 megawatts (MW), came online in 1986, 1987, and 1988. SEGS VIII (8) and IX (9), each with a net summer electric generation capacity of 88 MW, began operation in 1989 and 1990, respectively. SEGS 3, 4, 5, 6, 7, and 8 all ceased operation in 2021, leaving only SEGS 9 in operation as of December 31, 2021.

Solana Generating Station: a 296 MW project in Gila Bend, Arizona

Mojave Solar Project: a 275 MW project in Barstow, California

Genesis Solar Energy Project: a 250 MW project in Blythe, California

Nevada Solar One: a 69 MW plant near Boulder City, Nevada

Linear Fresnel reflectors

Linear Fresnel reflector (LFR) systems are similar to parabolic trough systems in that mirrors (reflectors) concentrate sunlight onto a receiver located above the mirrors. These reflectors use the Fresnel lens effect, which allows for a concentrating mirror with a large aperture and short focal length. These systems are capable of concentrating the sun's energy to about 30 times its normal intensity. Compact linear Fresnel reflector (CLFR)-also referred to as a concentrating linear Fresnel reflector-are a type of LFR technology with multiple absorbers within the vicinity of the mirrors. Multiple receivers allow the mirrors to change their position so they do not shade other reflectors. This improves system efficiency and reduces costs. A demonstration CLFR solar power plant was built near Bakersfield, California, in 2008, but it is currently not operating.

Solar power towers

A solar power tower system uses a large field of flat, sun-tracking mirrors called heliostats to reflect and focus sunlight onto a receiver on the top of a tower. Sunlight can be concentrated as much as 1,500 times. Some power towers use water as the heat-transfer fluid. Advanced designs are experimenting with molten nitrate salt because of its superior heat transfer and energy storage capabilities. The thermal energy-storage allows the system to produce electricity during cloudy weather or at night.

Ivanpah Solar Power Facility: a facility with three separate collector fields and towers with a combined net summer electric generation capacity of 393 MW in Ivanpah Dry Lake, California

Crescent Dunes Solar Energy Project: Crescent Dunes Solar Energy Project: a 110 MW one-tower facility with an energy storage component in Tonapah, Nevada

Solar dish/engines

Solar dish/engine systems use a mirrored dish similar to a very large satellite dish. To reduce costs, the mirrored dish usually has many small flat mirrors formed into a dish shape. The dish-shaped surface directs and focuses sunlight onto a thermal receiver, which absorbs and collects the heat and transfers it to an engine generator. The most common type of heat engine used in dish/engine systems is the Stirling engine. This system uses the fluid heated by the receiver to move pistons and create mechanical power. The mechanical power runs a generator or alternator to produce electricity.

Solar dish/engine systems always point straight at the sun and concentrate solar energy at the focal point of the dish. A solar dish's concentration ratio is much higher than linear concentrating systems, and it has a working fluid temperature higher than 1,380°F. The power-generating equipment of a solar dish can be placed at the focal point of the dish, making it well suited for remote locations, or the energy may be collected from many dishes and converted into electricity at a central point.

There are no utility-scale solar dish/engine projects in commercial operation in the United States.

Heating with the sun's energy

People use solar thermal energy to heat water and air. The two general types of solar heating systems are passive systems and active systems.

Passive solar space heating happens when the sun shines through the windows of a building and warms the interior. Building designs that use passive solar heating usually have south-facing windows that allow the sun to shine on solar heat-absorbing walls or floors during the day in the winter. The absorbed solar energy heats the building by natural radiation and convection at night. Window overhangs or shades block the sun from entering the windows during the summer to keep the building cool.

Active solar heating systems use a collector and a fluid that absorbs solar radiation. Fans or pumps circulate air or heat-absorbing liquids through collectors and then transfer the heated fluid directly to a room or to a heat storage system. Active solar water heating systems usually have a tank for storing solar heated water.

Solar collectors are either nonconcentrating or concentrating

Nonconcentrating collectors-The collector area (the area that intercepts the solar radiation) is the same as the absorber area (the area absorbing the radiation). Solar systems for heating water or air usually have nonconcentrating collectors. Flat-plate collectors are the most common type of nonconcentrating collectors for water and space heating in buildings and are used when temperatures lower than 200°F are sufficient.

A flat metal plate that intercepts and absorbs solar energy

A transparent cover that allows solar energy to pass through the cover and reduces heat loss from the absorber

A layer of insulation on the back of the absorber to reduce heat loss

Solar water heating collectors have metal tubes attached to the absorber. A heat-transfer fluid is pumped through the absorber tubes to remove heat from the absorber and transfer the heat to water in a storage tank. Solar systems for heating swimming pool water in warm climates usually do not have covers or insulation for the absorber, and pool water is circulated from the pool through the collectors and back to the pool.

Solar air heating systems use fans to move air through flat-plate collectors and into the interior of buildings.

Concentrating collectors -The area intercepting the solar radiation is greater, sometimes hundreds of times greater, than the absorber area. The collector focuses, or concentrates, solar energy onto an absorber. The collector usually moves so that it keeps sunlight focused on the absorber. Solar thermal power plants use concentrating solar collector systems because they can produce high temperature heat.

Solar energy systems/power plants do not produce air pollution, water pollution, or greenhouse gases. Using solar energy can have a positive, indirect effect on the environment when solar energy replaces or reduces the use of other energy sources that have larger effects on the environment.

Some toxic materials and chemicals are used to make the photovoltaic (PV) cells that convert sunlight into electricity. Some solar thermal systems use potentially hazardous fluids to transfer heat. Leaks of these materials could be harmful to the environment. U.S. environmental laws regulate the use and disposal of these types of materials.

As with any type of power plant, large solar power plants can affect the environment near their locations. Clearing land for construction and the placement of the power plant may have long-term effects on the habitats of native plants and animals. Some solar power plants may require water for cleaning solar collectors and concentrators or for cooling turbine generators. Using large volumes of ground water or surface water in some arid locations may affect the ecosystems that depend on these water resources. In addition, the beam of concentrated sunlight a solar power tower creates can kill birds and insects that fly into the beam.

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The sun has produced energy for billions of years and is the ultimate source for all of the energy sources and fuels that we use today. People have used the sun's rays (solar radiation) for thousands of years for warmth and to dry meat, fruit, and grains.

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Energy from moving air

Wind is caused by uneven heating of the earth's surface by the sun. Because the earth's surface is made up of different types of land and water, it absorbs the sun's heat at different rates. One example of this uneven heating is the daily wind cycle.

The daily wind cycle

During the day, air above the land heats up faster than air over water. Warm air over land expands and rises, and heavier, cooler air rushes in to take its place, creating wind. At night, the winds are reversed because air cools more rapidly over land than it does over water.

In the same way, the atmospheric winds that circle the earth are created because the land near the earth's equator is hotter than the land near the North Pole and the South Pole.

Wind energy for electricity generation

Today, wind energy is mainly used to generate electricity. Water-pumping windmills were once used throughout the United States and some still operate on farms and ranches, mainly to supply water for livestock.

How wind turbines work

Wind turbines use blades to collect the wind's kinetic energy. Wind flows over the blades creating lift (similar to the effect on airplane wings), which causes the blades to turn. The blades are connected to a drive shaft that turns an electric generator, which produces the electricity.

Electricity generation with wind

Total annual U.S. electricity generation from wind energy increased from about 6 billion kilowatthours (kWh) in 2000 to about 435 billion kWh in 2022. In 2022, wind turbines were the source of about 10.2% of total U.S. utility-scale electricity generation. Utility scale includes facilities with at least one megawatt (1,000 kilowatts) of electricity generation capacity

New technologies have decreased the cost of producing electricity from wind, and growth in wind power has been encouraged by government and industry incentives.

Wind power plants require careful planning

Operating a wind power plant is more complex than simply erecting wind turbines in a windy area. Wind power plant owners must carefully plan where to position wind turbines and must consider how fast and how often the wind blows at the site.

Good places for wind turbines are where the annual average wind speed is at least 9 miles per hour (mph)-or 4 meters per second (m/s)-for small wind turbines and 13 mph (5.8 m/s) for utility-scale turbines. Favorable sites include the tops of smooth, rounded hills; open plains and water; and mountain gaps that funnel and intensify wind. Wind resources are generally more favorable for electricity generation at higher elevations above the earth's surface. Large wind turbines are placed on towers that range from about 500 feet to as much as 900 feet tall.

Wind speeds are not the same across the country

Wind energy resources vary hourly and seasonally throughout the United States. For example, in Tehachapi, California, where numerous wind turbines are located, the wind blows more frequently from April through October than it does in the winter, and the wind is usually strongest in the afternoon. These fluctuations are a result of the extreme heat of the Mojave Desert during summer months. As the hot air over the desert rises, the cooler, denser air above the Pacific Ocean rushes through the Tehachapi mountain pass to take its place. In Montana, strong winter winds channeled through Rocky Mountain valleys create more intense winds during the winter.

Fortunately, the seasonal variations in wind speeds in California and Montana match the electricity demands of consumers in those states. In California, people use more electricity in the afternoon and during the summer. In Montana, people use more electricity, in general, during the winter.

Locations of U.S. wind power projects

In 2022, 42 states had utility-scale wind power projects, which together produced about 10% (435 billion kilowatthours [kWh]) of total U.S. utility-scale electricity generation. ¹ The five states with the most electricity generation from wind in 2022 were Texas, Iowa, Oklahoma, Kansas, and Illinois. These states combined produced about 57% of total U.S. wind electricity generation in 2022

International wind power

World wind electricity generation has also increased substantially in recent years. In 1990, 16 countries generated a total of about 3.6 billion kWh of wind electricity. In 2010, 105 countries generated about 340 billion kWh, and in 2020, 129 countries (includes Puerto Rico) generated about 1,597 billion kWh of wind electricity

Offshore wind power

The waters off the coasts of the United States have significant potential for electricity generation from wind energy. There are currently two operating U.S. offshore wind energy projects: the Block Island wind farm off the coast of Rhode Island, with 30 megawatts (MW) of electricity generation capacity, and the Coastal Virginia Offshore Wind pilot project with 12 MW electricity generation capacity. As of December 2022, wind project developers reported plans for about 7,500 MW of nameplate wind electricity generation capacity in waters off the coasts of Maryland, Massachusetts, New Jersey, Rhode Island, and Virgina, and about 20 MW in Ohio state waters on Lake Erie. European countries and China lead the world in offshore wind electric generation capacity. Many other countries have and are developing offshore wind energy projects.

Horizontal-axis turbines

Vertical-axis turbines

The size of wind turbines varies widely. The length of the blades is the biggest factor in determining the amount of electricity a wind turbine can generate. Small wind turbines that can power a single home may have an electricity generating capacity of 10 kilowatts (kW). The largest wind turbines in operation have electricity generating capacities of around 15,000 kW, and larger turbines are in development. Large turbines are often grouped together to create wind power plants, or wind farms, that provide power to electricity grids.

Horizontal-axis turbines are similar to propeller airplane engines

Horizontal-axis turbines have blades like airplane propellers, and they commonly have three blades. The largest horizontal-axis turbines are as tall as 20-story buildings and have blades more than 100 feet long. Taller turbines with longer blades generate more electricity. Nearly all of the wind turbines currently in use are horizontal-axis turbines.

Vertical-axis turbines look like egg beaters

Vertical-axis turbines have blades that are attached to the top and the bottom of a vertical rotor. The most common type of vertical-axis turbine-the Darrieus wind turbine, named after the French engineer Georges Darrieus who patented the design in 1931-looks like a giant, two-bladed egg beater. Some versions of the vertical-axis turbine are 100 feet tall and 50 feet wide. Very few vertical-axis wind turbines are in use today because they do not perform as well as horizontal-axis turbines.

Wind power plants, or wind farms, produce electricity

Wind power plants, or wind farms, are clusters of wind turbines that produce large amounts of electricity. A wind farm usually has many turbines scattered over a large area. One of the United States' largest wind farms is the Horse Hollow Wind Energy Center in Texas, which at the end of 2021, had 422 wind turbines spread over about 47,000 acres. The project has a combined electricity generating capacity of about 735 megawatts (or 735,000 kilowatts).

People have been using wind energy for thousands of years

People used wind energy to propel boats along the Nile River as early as 5,000 BC. By 200 BC, simple wind-powered water pumps were used in China, and windmills with woven-reed blades were grinding grain in Persia and the Middle East.

New ways to use wind energy eventually spread around the world. By the 11th century, people in the Middle East were using windpumps and windmills extensively for food production. Merchants and the Crusaders brought wind technology to Europe. The Dutch developed large windpumps to drain lakes and marshes in the Rhine River Delta. Immigrants from Europe eventually took wind energy technology to the Western Hemisphere.

American colonists used windmills to grind grain, to pump water, and to cut wood at sawmills. Homesteaders and ranchers installed thousands of windpumps as they settled the western United States. In the late 1800s and early 1900s, small wind-electric generators (turbines) were also widely used.

When power lines were built to transmit electricity to rural areas in the 1930s, wind pump and small turbine use began to decline. However, some ranches still use windpumps to supply water for livestock. Small wind turbines are becoming more common again, mainly to supply electricity in remote and rural areas.

Wind energy use expanded in the wake of oil shortages and environmental concerns

The oil shortages of the 1970s changed the energy environment for the United States and the world. The oil shortages created an interest in developing ways to use alternative energy sources, such as wind energy, to generate electricity. The U.S. federal government supported research and development of large wind turbines. In the early 1980s, thousands of wind turbines were installed in California, largely because of federal and state policies that encouraged the use of renewable energy sources.

In the 1990s and 2000s, the U.S. federal government established incentives to use renewable energy sources in response to a renewed concern for the environment. The federal government also provided research and development funding to help reduce the cost of wind turbines and offered tax and investment incentives for wind power projects. In addition, state governments enacted new requirements for electricity generation from renewable sources, and electric power marketers and utilities began to offer electricity generated from wind and other renewable energy sources (sometimes called green power) to their customers. These policies and programs resulted in an increase in the number of wind turbines and in the amount of electricity generated from wind energy.

The share of total U.S. electricity generation from wind energy has grown from less than 1% in 1990 to about 10.2% in 2022. Financial and other incentives for electricity generation with wind energy have resulted in a large expansion of wind energy use in the United States and Europe. China has invested heavily in wind energy and is now the world's largest wind electricity generator. In 1990, 16 countries generated a total of about 3.6 billion kWh of wind electricity. In 2021, at least 128 countries (including Puerto Rico) generated about 1,808 billion kWh of wind electricity.

Wind is an emissions-free source of energy

Wind is a renewable energy source. Overall, using wind to produce energy has fewer effects on the environment than many other energy sources. Wind turbines do not release emissions that can pollute the air or water (with rare exceptions), and they do not require water for cooling. Wind turbines may also reduce the amount of electricity generation from fossil fuels, which results in lower total air pollution and carbon dioxide emissions.

An individual wind turbine has a relatively small physical footprint. Groups of wind turbines, sometimes called wind farms, are located on open land, on mountain ridges, or offshore in lakes or the ocean.

Wind turbines have effects on the environment

Modern wind turbines can be very large machines, and they may visually affect the landscape. A small number of wind turbines have also caught fire, and some have leaked lubricating fluids, but these occurrences are rare. Some people do not like the sound that wind turbine blades make as they turn in the wind. Some types of wind turbines and wind projects cause bird and bat deaths. These deaths may contribute to declines in the population of species also affected by other human-related impacts. The wind energy industry and the U.S. government are researching ways to reduce the effect of wind turbines on birds and bats.

Most wind power projects on land require service roads that add to the physical effects on the environment. Producing the metals and other materials used to make wind turbine components has impacts on the environment, and fossil fuels may have been used to produce the materials. Although most of the materials used to make wind turbines can be reused or recycled, turbine blades, as most are currently constructed, cannot be recycled. Researchers at the National Renewable Energy Laboratory (NREL) established an approach to manufacturing wind turbine blades, employing a thermoplastic resin system. These thermoplastic resins enable a manufacturing process that allows wind turbine blades to be recycled at their end of life and also reduces the energy required to manufacture blades.

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Wind is caused by uneven heating of the earth's surface by the sun. Because the earth's surface is made up of different types of land and water, it absorbs the sun's heat at different rates. One example of this uneven heating is the daily wind cycle.

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Solar energy is light, heat, and other forms of energy given off by the Sun. Solar energy can be collected and used to heat buildings and to make electricity. Solar Heating...

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Do you want to know how solar panels work and how they can benefit you? Solar energy is a great way to create renewable electricity with fewer emissions than traditional methods of power generation. It's an idea that has been around for decades, but now it's being used in many homes, businesses, and schools! In this blog post, we'll explain the basics of solar energy in easy-to-understand terms so that kids can learn more about this amazing resource. We'll go through some common questions about solar panels like: How do they work? What are their benefits? And what are the fun facts about solar panels? Read on to find out the answers!

What is Solar Energy?

Do you want to know how does solar energy work for kids? Here is the answer for you! Solar energy is the power we get from the sun. The sun is like a big ball of fire in the sky that gives off light and heat. But did you know that it also gives us a special kind of energy that we can use? That's called solar energy!

When the sun shines, it sends out tiny particles of energy called photons. These photons travel all the way from the sun to Earth. We can't see them, but they're there, carrying lots of energy with them.

Now, we have something amazing called solar panels. These panels are made up of special materials that can capture the sun's energy. When sunlight hits the solar panels, they absorb the energy from the photons.

Once the solar panels have turned the sunlight into electricity, we can use that electricity to power things like our homes, schools, and even toys. Isn't that cool?

The best part about solar energy is that it's renewable. That means the sun keeps shining every day, and we'll always have more solar energy to use. Plus, using solar energy is good for the environment because it doesn't make any pollution like other sources of energy do.

So, solar energy is the power we get from the sun. It's clean, renewable, and can be turned into electricity using special panels called solar panels. It's a fantastic way to use the sun's energy to help us in lots of different ways.

How Do Solar Panels Work?

Solar electricity starts with sunlight. When the sun shines, it gives off light and energy. Solar panels are special panels that capture the sunlight. They are made up of small units called photovoltaic cells, which are like tiny power factories.

Photovoltaic cells are special cells inside solar panels. They have an amazing ability to turn sunlight into electricity! When sunlight shines on these cells, they get really excited and start moving around. This movement creates something called an electric current, which is like a superpower we can use. It can power our devices, light up our homes, and do all sorts of cool things. The more photovoltaic cells there are, the more electricity we can make. So, these little cells are like tiny superheroes that help us capture the sun's energy and turn it into usable electricity. It's like the panels are doing a magic trick!

Sometimes, solar panels make more electricity than we need right away. In those cases, we can store the extra electricity in batteries. These batteries can keep the electricity for later, like when it's nighttime or cloudy and the sun isn't shining as much.

And that's how solar electricity works! It all starts with the sun, the solar panels capture its energy, and the photovoltaic cells inside the panels turn that energy into electricity that we can use. It's an amazing way to use the sun's power to help us and our planet.

Benefits of Solar Panels

Solar panels have many advantages. Let's explore some of them!

Clean and Renewable Energy

Solar panels give us clean and renewable energy. They use the power of the sun, which is always shining, to create electricity. Unlike other sources of energy, like coal or gas, solar energy doesn't make pollution or release harmful gases into the air. So, it's good for the Earth and helps keep our air clean and healthy.

Saving Money on Electricity Bills

When we use solar panels to make electricity, we can save money on our electricity bills. How cool is that? Solar energy is free because it comes from the sun. So, when we use solar panels to power our homes or schools, we don't have to pay as much for electricity from other sources. That means more money in our pockets to do other fun things!

Helping the Environment

Solar panels are great for the environment. When we use solar energy, we're not using up Earth's resources like coal or gas. We're also reducing the amount of pollution that comes from using those other energy sources. Solar panels help us protect nature, animals, and our planet, so we can all live in a healthier and happier world.

Long-Lasting and Low Maintenance

Solar panels are built to last a long time. They are made of strong materials that can withstand different weather conditions. Once they're installed, solar panels don't need much maintenance. They keep working and making electricity for many years without needing a lot of repairs. That means we can enjoy the benefits of solar energy for a long time without having to worry too much about taking care of the panels.

So, solar panels have many benefits for us and the environment. They give us clean and renewable energy, help us save money on electricity bills, protect the environment, and last a long time with low maintenance. It's like having our own little sun-powered superheroes helping us and our planet every day!

Fun Facts About Solar Panels

Solar panels are not only fascinating but also have some exciting facts associated with them. Let's start to explore!

Solar-Powered Inventions

Did you know that solar panels can power all sorts of cool inventions? People use solar energy to make things like solar-powered cars, boats, and even planes! These inventions use the power of the sun to move and do amazing things. It's like having a supercharged battery that never runs out because it's always getting energy from the sun.

Largest Solar Power Plants

There are some really big solar power plants in the world. These are places where many solar panels are installed together to make a lot of electricity. Some of these power plants are so huge that they can power thousands of homes and buildings! It's like having a gigantic sun-catching machine that produces a lot of clean energy for many people to use.

Solar Energy in Space

Solar energy is not just for Earth; it's also used in space! Astronauts and satellites use solar panels to get energy in space. They are explorers that use the sun's power to travel and explore the mysteries of the universe. In fact, many satellites have big solar panels that collect sunlight and turn it into electricity to power all the amazing things they do up there.

These fun facts show us how solar panels are used in exciting ways. They power inventions, provide electricity for big power plants, and even work in outer space. It's like the sun's energy is being used everywhere, making our lives better and more fun!

Exploring Solar Power with Your Kids

Introducing children to the concept of solar energy and educating them about how solar panels work is a fantastic way to foster their understanding of renewable energy. Engaging in a practical activity such as installing a solar panel with your kids can provide them with hands-on experience and further deepen their knowledge of solar power.

By involving children in the process of setting up a solar panel, they can witness firsthand how sunlight is converted into usable energy. This interactive activity not only sparks their curiosity but also helps them appreciate the significance of harnessing renewable resources for a sustainable future.

To enhance your solar panel installation project, we recommend considering the . Anker is renowned for its high-quality and reliable products in the field of solar energy.

The Anker 531 Solar Panel provides an excellent combination of efficiency, durability, and affordability, making it an ideal choice for both beginners and experienced users. By using the Anker 531 Solar Panel with a 3-angel adjustment function, you can demonstrate to your children the functionality and effectiveness of solar power generation and see how angels affect power efficiency. Together, you can explore the various components of the solar panel, such as the photovoltaic cells that capture sunlight and convert it into electricity.

This hands-on experience will enable your kids to comprehend how solar energy can be harnessed to power devices and reduce reliance on non-renewable energy sources.

Conclusion

Congratulations, young solar enthusiasts! In this blog, we embarked on an exciting journey to uncover the secrets of solar power for kids. Now, armed with knowledge and inspiration, it's time to take action! Consider installing a solar panel to experience the wonders of solar energy with kids firsthand. Engaging in this hands-on activity will deepen their understanding and empower them to make a positive impact on our planet. Together, we can create a greener, cleaner, and more sustainable future.

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How Do Solar Panels Work for Kids? A Child-Friendly Explanation

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Learn the science behind solar energy with this clear explanation of how do solar panels work for kids. Uncover the benefits and fun facts about solar energy!