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Design an energy system using an alternative energy source

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For something we use every day, energy is a pretty mysterious concept. This Lab investigates what energy is, how it can be converted into useful forms, and why some sources are running low. In our Research Challenge, you'll use scientific data to design renewable energy systems for cities across the U.S.-and compete with others to see whose designs can produce the most power.

Video Intro About this Lab Educator Guide

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energy renewable power wind solar geothermal biomass fossile fuels smart grid

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For something we use every day, energy is a pretty mysterious concept. This Lab investigates what energy is, how it can be converted into useful forms, and why some sources are running low. In our Research Challenge, you'll use scientific data to design renewable energy systems for cities across the U.S.-and compete with others to see whose designs can produce the most power.

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An interactive graph on energy use in the United States

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The National Academies presents: What You Need to Know About Energy

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Want to understand the basics of America's current energy situation? The National Academies, advisers to the nation on science, engineering, and medicine, provides objective information about the United States' current energy sources and uses, as well as a look forward to the future of energy.

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Journal of Advances in Modeling Earth Systems (JAMES)

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All forms of electric vehicles (EVs) can help improve fuel economy, lower fuel costs, and reduce emissions.

Energy Security

The United States became a net exporter of petroleum in 2020 with exports surpassing imports, although imports of 8.32 million barrels per day in 2022 remained an important part of balancing supply and demand for domestic and international markets. Overall, the transportation sector accounts for approximately 30% of total U.S. energy needs and 70% of U.S. petroleum consumption. Using more energy efficient vehicles like hybrid and electric vehicles supports the U.S. economy and helps diversify the U.S. transportation fleet. The multiple fuel sources used to generate electricity results in a more secure energy source for the electrified portion of the transportation sector. All of this adds to our nation's energy security.

Hybrid electric vehicles (HEVs) typically use less fuel than similar conventional vehicles because they employ electric-drive technologies to boost vehicle efficiency through regenerative braking-recapturing energy otherwise lost during braking. Plug-in hybrid electric vehicles (PHEVs) and all-electric vehicles, also referred to as battery electric vehicles (BEVs), are both capable of being powered solely by electricity, which is produced in the United States from natural gas, coal, nuclear energy, wind energy, hydropower, and solar energy.

Costs

Although energy costs for EVs are generally lower than for similar conventional vehicles, purchase prices can be significantly higher. Prices are likely to equalize with conventional vehicles, as production volumes increase and battery technologies continue to mature. Also, initial costs can be offset by fuel cost savings, a federal tax credit, and state and utility incentives. The federal Clean Vehicle Credit is available for EV purchases from manufacturers that have not yet met certain thresholds of vehicle sales. It provides a tax credit of $3,750 to $7,500 for new purchases by eligible individuals and businesses, with the amount determined by the battery capacity, critical mineral sourcing, battery components, and vehicle cost. Some states and electric utilities also offer incentives, many of which can be found in the Laws and Incentives database. For more information on available incentives, connect with your local Clean Cities coalition.

Use the Vehicle Cost Calculator to compare lifetime ownership costs of individual models of electric vehicles and conventional vehicles.

Fuel Economy

Electric vehicles can reduce fuel costs dramatically because of the high efficiency of electric-drive components. Because all-electric vehicles and PHEVs rely in whole or part on electric power, their fuel economy is measured differently than that of conventional vehicles. Miles per gallon of gasoline equivalent (MPGe) and kilowatt-hours (kWh) per 100 miles are common metrics. Depending on how they are driven, today's light-duty all-electric vehicles (or PHEVs in electric mode) can exceed 130 MPGe and can drive 100 miles consuming only 25-40 kWh.

HEVs typically achieve better fuel economy and have lower fuel costs than similar conventional vehicles. For example, FuelEconomy.gov lists the 2023 Toyota Corolla Hybrid at an EPA combined city-and-highway fuel economy estimate of 50 miles per gallon (MPG), while the estimate for the conventional 2023 Corolla (four cylinder, automatic) is 35 MPG. Use the Find A Car tool on FuelEconomy.gov to compare fuel economy ratings of individual hybrid and conventional models.

The fuel economy of medium- and heavy-duty all-electric vehicles and PHEVs is highly dependent on the load carried and the duty cycle, but in the right applications, all-electric vehicles maintain a strong fuel-to-cost advantage over their conventional counterparts.

Infrastructure Availability

All-electric vehicles and PHEVs have the benefit of flexible charging because the electric grid is near most locations where people park. To safely deliver energy from the electric grid to a vehicle's battery, an EV charging station, sometimes referred to as electric vehicle supply equipment (EVSE), is needed. Drivers can charge overnight at a residence, including multifamily housing, as well as the workplace or a public charging station when available. PHEVs have added flexibility because they can also refuel with gasoline or diesel (or possibly other fuels in the future) when necessary.

Public charging stations are not as ubiquitous as gas stations. Charging equipment manufacturers, automakers, utilities, Clean Cities coalitions, states, municipalities, and government agencies are rapidly establishing a national network of public charging stations. The number of publicly accessible charging stations in the United States reached more than 53,000 in 2023, offering more than 137,000 charging ports, according to the Alternative Fueling Station Locator. Search for electric charging stations near you.

Emissions

Electric and hybrid vehicles can have significant emissions benefits over conventional vehicles. All-electric vehicles produce zero tailpipe emissions, and PHEVs produce no tailpipe emissions when operating in all-electric mode. HEV emissions benefits vary by vehicle model and type of hybrid power system.

The life cycle emissions of an electric vehicle depend on the source of the electricity used to charge it, which varies by region. In geographic areas that use relatively low-polluting energy sources for electricity production, electric vehicles typically have a life cycle emissions advantage over similar conventional vehicles running on gasoline or diesel. In regions that depend heavily on conventional electricity generation, electric vehicles may not demonstrate a strong life cycle emissions benefit. Use the Electricity Sources and Emissions Tool to compare fuel-cycle emissions by vehicle type and state.

Batteries

The advanced batteries in electric vehicles are designed for extended life but will wear out eventually. Several manufacturers of electric vehicles are offering 8-year/100,000-mile battery warranties. Predictive modeling by the National Renewable Energy Laboratory indicates that today's batteries may last 12 to 15 years in moderate climates (8 to 12 years in extreme climates). In addition to climate, other factors impacting battery life include driving and charging patterns, battery cell chemistry and design, and the vehicle-battery-environment thermal system.

Check with your dealer for model-specific information about battery life and warranties. Although manufacturers have not published pricing for replacement batteries, some are offering extended warranty programs with monthly fees. If the batteries need to be replaced outside the warranty, it may be a significant expense. Battery prices are expected to continue declining as battery technologies improve and production volumes increase.

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Electric Vehicle Benefits and Considerations

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All forms of electric vehicles (EVs) can help improve fuel economy, lower fuel costs, and reduce emissions. The United States became a net exporter of petroleum in 2020 with exports surpassing imports, although imports of 8.32 million barrels per day in 2022 remained an important part of balancing supply and demand for domestic and international markets.

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on fuel economy

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FuelEconomy.gov - The official U.S. government source for fuel economy information.

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EPA gas mileage, safety, air pollution, and greenhouse gas estimates for new and used cars and trucks. Improve the MPG of your vehicle with our gas mileage tips.

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Energy And Cars: What Does The Future Hold? | Free Lesson Plans | Teachers

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The Lesson Plan Library offers high school lesson plans covering all major school subjects and special interests.

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To gas power

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10 alternatives to the gasoline-powered engine

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There's no shortage of greener ways to run a car. How viable they are is another story.

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Quick reference

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Six Types of Fuels Used in Today's Vehicles

by Lee Morgan

Today's vehicles run on a variety of fuels, some of which you probably aren't aware of. While it's true than the vast majority of vehicles run on gasoline, the technology to burn other fuels to meet our transportation needs does exist, with specific advantages and disadvantages for each.

About the Author

Lee Morgan is a fiction writer and journalist. His writing has appeared for more than 15 years in many news publications including the "Tennesseean," the "Tampa Tribune," "West Hawaii Today," the "Honolulu Star Bulletin" and the "Dickson Herald," where he was sports editor. He holds a Bachelor of Science in mass communications from Middle Tennessee State University.

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Six Types of Fuels Used in Today's Vehicles

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Today's vehicles run on a variety of fuels, some of which you probably aren't aware of. While it's true than the vast majority of vehicles run on gasoline, the technology to burn other fuels to meet our transportation needs does exist, with specific advantages and disadvantages for each.

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Shows how a generator works by "turning the crank".

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Locations of places to charge

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Google, Inc. is about to take the guesswork out of finding an electric vehicle charging station. The Internet giant has partnered up with the Department of Energy's National Renewable Energy Laboratory and other stakeholders to use Google Maps as the primary platform for coordinating a database that provides up-to-date information on the whereabouts of EV charging stations nationwide. The project is being conducted through DOE's Alternative Fuels and Advanced Vehicles Data Center, which already features an online alternative fuels location finder that includes EV charging stations.

$5 Million in New Funds to Kickstart EV Charging Stations

The new partnership is coordinated with a $5 million funding program from DOE, which will pair up local governments with private companies to speed up the development of an EV charging station infrastructure. On the government side, that involves updating and streamlining permitting procedures for charging stations, as well as developing a framework of incentives to encourage the use of EV's by consumers, businesses, and organizations. On the business side, that means the arrival of new opportunities for companies that design and construct charging stations to expand more rapidly and create new green jobs.

Electric Vehicle Explosion

EV's are already starting to make inroads into fleet vehicles, including government fleets, so the new initiative isn't starting from scratch. It also has a head start as part of the Clean Cities Initiative, a DOE program that has been going on since 1993 to reduce auto emissions. The $5 million will be doled out on a competitive basis, so it will be interesting to see how that affects the dynamic between state and local governments, given that at least some of the probable applicants are located in states where governors have already turned down funding for federal transportation projects (namely, high speed rail).

Google and Clean Energy

Aside from the EV charging station project, Google is also having a hand in promoting solar energy. Earlier this year, researchers at the University of California - San Diego teamed up with Google Earth to fine-tune a solar power map that enables California home owners and solar companies to calculate the most cost-effective placement of rooftop solar panels, coordinating peak use rates along with the sun's location.

Related Article:

Image: Power plug by Samuel M. Livingston

About the Author

Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina's articles are reposted frequently on Reuters, Scientific American, and many other sites. Views expressed are her own. Follow her on Twitter @TinaMCasey and Google+.

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Google Maps Will Guide EV Drivers to Charging Stations

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Google, Inc. is about to take the guesswork out of finding an electric vehicle charging station. The Internet giant has partnered up with the Department of Energy's National Renewable Energy Laboratory and other stakeholders to use Google Maps as the primary platform for coordinating a database that provides

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Using Google Earth to evaluate effectiveness of solar panels by geographic area. Focuses on homes, but might have applications to our project

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Using Google Earth to evaluate effectiveness of solar panels by geographic area. Focuses on homes, but might have applications to our project

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Clean Power

Researchers at the University of California, San Diego have harnessed the power of Google Earth to fine-tune a free solar map that works like a kind of crystal ball for solar power. The map helps homeowners and other photovoltaic installers to determine the most effective angle for solar panels in different parts of the state. It also helps to predict the amount of power a solar installation could generate. Tools like this are going to become increasingly important as solar energy competes for installation dollars with other emerging small-scale alternative energy technologies including micro wind power and fuel cells.

Predicting Solar Energy

According to an article from the UC Jacobs School of Engineering, Professor Jan Kleissl and his research team have correlated solar production with demand, in order to squeeze the most valuable power out of an installation. Electricity rates generally go up during periods of peak use, so it makes sense to build a solar installation that takes the best advantage of the sun's location during these times.

Distributed Solar Energy and Green Jobs

Along with making solar energy a more economical choice for individual homeowners, the new map could help speed the development of more distributed solar networks. Distributed solar can help reduce the need to build new central power plants, while spreading more green jobs in local communities. As demonstrated by President Obama's job-creation record in the first two years of his term, green jobs are an economic powerhouse despite the obstruction of legislators with an interest in preserving the dominance of fossil fuels. If legislators are serious about getting this nation on the right fiscal track, it's time to stop coddling out-of-date, destructive energy sources.

Image: Crystal ball by Bitterjug on flickr.com.

Tags: google-earth, micro wind power, University of California

About the Author

Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina's articles are reposted frequently on Reuters, Scientific American, and many other sites. Views expressed are her own. Follow her on Twitter @TinaMCasey and Google+.

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New Google Earth Map Lets Homeowners Predict Solar Power

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January 12th, 2011 by Tina Casey Researchers at the University of California, San Diego have harnessed the power of Google Earth to fine-tune a free solar map that works like a kind of crystal ball for solar power.

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How do they work?

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Battery electric vehicles, or BEVs, use electricity stored in a battery pack to power an electric motor and turn the wheels. When depleted, the batteries are recharged using grid electricity, either from a wall socket or a dedicated charging unit. Since they don't run on gasoline or diesel and are powered entirely by electricity, battery electric cars and trucks are considered "all-electric" vehicles.

When driven, BEVs don't produce tailpipe pollution-they don't even have a tailpipe. However, the electricity they use may produce heat-trapping gases and other pollution at the source of its generation or in the extraction of fossil fuels. The amount of pollution produced depends on how the electricity is made. In the United States, battery electric cars charged off the dirtiest coal-dominated grid still produce less pollution than their gasoline-powered counterparts. BEVs powered by renewable energy sources like wind or solar are virtually emission-free.

Not using gasoline or diesel also means that battery electric cars are significantly cheaper to fuel than conventional vehicles. Exact comparisons depend on the vehicle model and fuel prices, but driving a BEV can save drivers over $1,000 annually in gasoline money.
New data show EVs continue to get cleaner. See our blog
Battery electric vehicle features

Like other electric and hybrid-electric vehicles, BEVs minimize wasted energy by turning the car off when stopped (" idle-off") and by charging the battery when braking (" regenerative braking "). Electric motors are also inherently more energy-efficient than gasoline or diesel engines.

Battery electric cars have the added benefit of home recharging. A 240-volt outlet, similar to those used for clothes dryers, can charge a vehicle overnight. Fully-charged, most battery electric cars have a driving range of between 70 to 100 miles, well within the day-to-day range requirements of most Americans, though some BEVs can go up to 265 miles on a single charge. An increasing number of public and workplace charging stations provide added charging capacity.

More subjectively, many drivers appreciate the driving experience provided by all-electric cars. Electric motors generate near-instant torque, or turning-force, while the torque of internal combustion engines increases in tandem with the engine's revolutions (RPM). This means that BEVs have extremely fast acceleration and a "light" or "zippy" feel compared to conventional cars and trucks.

Differences between battery electric cars and other EVs

Plug-in hybrid electric vehicles have both an electric motor and a conventional gasoline or diesel engine. Compared to a battery electric vehicle, this extends the total driving range but lowers the all-electric range. Conventional hybrids, which can't be plugged in, aren't considered electric vehicles. Learn more about how plug-in vehicles work >

Fuel cell electric vehicles convert hydrogen gas into electricity to power an electric motor and battery. Fuel cell vehicles are a relatively new technology in passenger vehicles, but have a substantial carbon-cutting role to play alongside other all-electric vehicles. Learn more about how fuel cells and fuel cell vehicles work >

Learn more about electric vehicle technology here, including its potential as a nationwide oil-saving solution.

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Battery electric vehicles, or BEVs, use electricity stored in a battery pack to power an electric motor and turn the wheels. When depleted, the batteries are recharged using grid electricity, either from a wall socket or a dedicated charging unit.

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Students learn how engineers transform wind energy into electrical energy by building their own miniature wind turbines and measuring the electrical current they produce. They explore how design and position affect the electrical energy production.
This engineering curriculum meets Next Generation Science Standards (NGSS).

Learning Objectives

After this activity, students should be able to:

Describe the transformations of energy that occur in a wind turbine.

Describe how engineers construct a wind turbine.

Explain how the design and position of a wind turbine affects the electrical energy produced by it.

Educational Standards
Suggest an alignment not listed above

Materials List

Each group needs:

small DC toy motor; available at science and electronics supply catalogs, websites and stores

2 pieces of thin electrical wire with alligator clips, each about 50 cm or 20 inches long

rubber band

stiff ruler

cylindrical-shaped cork, at least 2 cm or ¾ inch in diameter; alternative to cork: Styrofoam ball

4 paperclips

scotch tape

scissors

4 pieces of cardboard, each 3 x 5 cm

(optional) safety goggles or glasses

Wind Turbine Worksheet, one per team

For the entire class to share:

1 or 2 small electric fans or hair dryers

DC voltmeter; available from electronics catalogs, websites and stores

Introduction/Motivation

Have you ever felt a really strong wind? How does it feel? Have you ever felt blown around by the wind? Wind can do work for us by moving things around. Sometimes we do not want the wind to move things, like when it blows our papers around and we have to pick them up. But sometimes we want the wind to move things around for us. For example, when the wind moves the blades of a wind turbine (a machine that converts the moving energy of wind into mechanical energy and electrical energy), the turbine produces some useful energy (in the form of electricity).

Let's talk about what happens to get electricity from the wind. First of all, to change the wind energy to electricity, rotor blades spin the hub (center) of the turbine. Inside the turbine is an electric generator, which is a rotating machine that supplies an electrical output with voltage and current. The rotating action of the hub turns a magnet inside a coil of wire in the generator, producing electricity.

A turbine is basically a motor connected backwards. Rather than connecting a battery to the motor to make something move, a wind turbine is connected to the motor, and its movement generates electricity. You can measure how much electricity (voltage) is produced with a voltmeter.

Engineers design wind turbines that turn the kinetic energy of the wind (the movement of the wind) into mechanical or electrical power.

So, when does a wind turbine work best? The power produced by a wind turbine depends on elevation, wind speed and air temperature. Wind speeds of at least 23 kilometers (14 miles) per hour are required to generate electricity. Wind turbines are best located in areas in which wind speeds are 26-32 kph (16-20 mph) with the windmill at 50 meters (55 yards) high. That's pretty high up. The greater the wind speed, the more power generated. Think about it: when the wind blows harder, those papers move around even faster. If the wind speed doubles, the power available to a wind turbine increases by a factor of eight. That means the power doubles and doubles and doubles again!

Today, we are going to act as if we are engineers and create small-scale wind turbines that convert wind energy connected to a motor into electrical energy (voltage). Then, we will measure how the wind speed affects our little wind turbines. This will help us understand what engineers need to know when designing and placing wind turbines in the best locations.

Vocabulary/Definitions

electrical energy: Electrical energy exists when charged particles attract or repel each other. Television sets, computers and refrigerators use electrical energy.

energy: The ability to do work.

generator: A device that transforms mechanical energy into electrical energy.

hub: The center part of a wheel, fan or propeller.

kinetic energy: The energy of motion. For example, a spinning top, a falling object and a rolling ball all have kinetic energy. The motion, if resisted by a force, does work. Wind and water both have kinetic energy.

mechanical energy: Mechanical energy is energy that can be used to do work. It is the sum of an object's kinetic and potential energy.

potential energy: Potential energy is the energy stored by an object as a result of its position. A roller coaster at the top of a hill has potential energy.

renewable energy: Energy that is made from sources that can be regenerated. Sources include solar, wind, geothermal, biomass, ocean and hydro (water).

rotor: The rotating part of an electrical or mechanical device.

turbine: A machine in which the kinetic energy of a moving fluid is converted into mechanical energy by causing a series of buckets, paddles or blades on a rotor to rotate.

voltmeter: An instrument that measures electromotor force in units called volts.

wind turbine: A machine that converts the moving energy of wind into mechanical and/or electrical energy.

Procedure

Before the Activity

It is helpful to build and test a wind turbine in advance, to use as an example.

Gather materials and make copies of the Wind Turbine Worksheet.

Attach wires to the DC motors.

Set up a test station with a voltmeter and a wind source (fan or hair dryer) where teams can take turns measuring the output of their wind turbine generators.

Test to make sure the motors and voltmeters are working correctly.

With the Students

1. Divide the class into teams of two students each. Provide each team with materials and a work space.

2. Emphasize safety precautions. Students should never touch any bare or exposed metal in a circuit that is generating electricity.

3. Have students use a rubber band to attach the electric motor to the ruler with the motor shaft positioned at the end of the ruler (see Figure 1). The ruler serves as a platform for the wind turbine.

Figure 1. The activity setup: A wind turbine prototype hooked to a voltmeter.

1. Straighten out the lower part of each of four paperclips.

2. Cut out four 3 x 5 cm pieces of cardboard. Use tape to firmly attach a piece of cardboard to each paperclip.

3. Stick the straightened part of each paperclip into the curved sides of a cork to create four turbine blades. Be sure to space the blades equally around the cork.

4. Push the cork into the motor shaft. Make sure the shaft goes into the exact center of the cork.

5. Rotate the blade in the cork so that it is at a 45º angle to the flat plane of the edge of the ruler. You have completed your wind turbine!

Figure 2. The activity setup.

6. In teams, have students bring their wind turbines to the testing station.

7. For one team at a time, use alligator clips to attach the free ends of the wires to a DC voltmeter. While waiting, have other teams work on the worksheet.

8. Start by placing the wind turbine about 30 cm (12 inches) away from the wind source (fan or hair dryer). Adjust the distance, depending on the strength of the wind source.

9. Turn on the wind source and measure the voltage produced. Record on the worksheet.

10. Repeat with the wind turbine at different distances from the wind source.

11. Have team members work together to complete the worksheet.

12. After all teams have had a turn at the test station and have completed their worksheets, conclude with a class discussion. Describe the movement of energy in your generator, starting with the wind and ending at the voltmeter. Review each team's results and observations. Did the turbine design of any team produce more voltage at the same distance, compared to the rest? Did anyone adjust the angle of the blades? What did that do? What happened as you moved your wind turbine closer or farther away from the wind source? How might you alter your turbine design or position to better capture the wind and produce more voltage? What factors might engineers consider when deciding where to put a wind turbine generator or a wind farm?

Worksheets and Attachments

Safety Issues

Emphasize safety precautions. Students should never touch any bare or exposed metal in a circuit that is generating electricity.

Remind students not to put anything, including their hands, near the wind turbine or fan while it is rotating.

Troubleshooting Tips

In advance of the activity, test the motors and voltmeters to make sure they are working correctly.

If the activity does not work well, try the following alternative: Attach a DC motor to a wheel. Duct tape 2 Popsicle sticks to the wheel to form a straight line. Duct tape a rectangular piece of cardboard to each Popsicle stick at such an angle as to create spin when wind blows past it. Tape the motor to a ruler to serve as a handle.

If time is limited, speed up the activity by bringing in two fans to provide two test stations.

Assessment

Pre-Activity Assessment

Brainstorming: Have students engage in open discussion to think of how wind could be used as an energy source. Remind them that no idea or suggestion is "silly." All ideas should be respectfully heard. Write their ideas on the classroom board.

Activity Embedded Assessment

Worksheet: Have student teams record their measurements and observations on the Wind Turbine Worksheet. Review their answers to gauge their mastery of the subject.

Post-Activity Assessment

Question/Answer: Ask the students and discuss as a class:

When can wind power be used? (Answer: The wind must have a high enough speed.)

Why might engineers be interested in developing wind power in a location? (Answer: Wind is a renewable energy resource. Wind power does not produce greenhouse gases or pollution. Using wind power reduces the consumption of non-renewable fossil fuels.)

Why are large wind turbines often located on hills? (Answer: Wind speed is greater up high above the ground.)

If we remove the motor from the rotor of the wind turbine, we will not be able to produce electricity, but we will still be able to do work with our windmill. What kind of work could we do? (Answer: We could do mechanical work by making the blades of the windmill move.)

Engineer Challenge Question: Ask students to think about the following engineering design problem. Have them discuss their answers in teams and share their thoughts with the class.

A homeowner wants to use a wind turbine to supply electricity for her home, but no hills are near the house. Where could an engineer place the wind turbine? (Answer: As high up as possible, such as on a pole above the roof, or on a separate structure that puts it up very high in the air.)

Activity Extensions

Have students design their own sets of blades, varying the size, shape, material and number. Have students attach these new blades to the motor and adjust them at various angles to produce the greatest voltage. Have them record their variables and results in a data chart they create during the activity. Have students share and compare their designs by giving brief engineering reports to the class.

Explore how wind velocity affects the amount of electricity produced by changing fan speeds.

Explore the Renewable Energy Living Lab for real wind measurement, energy collections systems and real-world data. See: http://www.teachengineering.org/livinglabs/

Activity Scaling

For lower grades, have the motor setup already prepared. Just have the students create the blades on the paperclips and press them into the cork. Help students measure the voltage generated by their wind turbines.

For upper grades, have students graph the voltage produced as a function of fan distance. Have students solve the power problems in the Wind Power! Math Worksheet.

References

Buy into Wind and Fight Global Warming! Clean Air-Cool Planet. Accessed October 20, 2005. (Good photographs of the first large utility-scale wind turbine installed on the Rosebud Sioux Indian Reservation) http://www.cleanair-coolplanet.org/action/windbuilders.php

Renewable Energy Lesson Plans. Infinite Power, Texas State Energy Conservation Office. Accessed October 19, 2005. http://www.infinitepower.org/lessonplans.htm

How Wind Turbines Work. Updated October 3, 2005. Wind & Hydropower Technologies Program, Energy Efficiency and Renewable Energy, U.S. Department of Energy. Accessed October 19, 20015. (Great animation of a wind turbine generating electricity) http://www1.eere.energy.gov/wind/wind_animation.html

Contributors Xochitl Zamora-Thompson; Sabre Duren; Natalie Mach; Malinda Schaefer Zarske; Denise W. Carlson

Copyright © 2005 by Regents of the University of Colorado

Supporting Program Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder

Acknowledgements

The contents of this digital library curriculum were developed under grants from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and the National Science Foundation (GK-12 grant no. 0338326). However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.

Last modified: August 13, 2018

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Wind Power! Designing a Wind Turbine - Activity

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Students learn how engineers transform wind energy into electrical energy by building their own miniature wind turbines and measuring the electrical current they produce. They explore how design and position affect the electrical energy production. This engineering curriculum meets Next Generation Science Standards (NGSS).

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Renewable Energy Projects for the Classroom 

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Renewable Energy Projects for the Classroom 

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Inquiry based lab on generating energy through the use of wind power

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KidWind - Teaching the World about Renewables

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Wind and solar energy lessons and workshops for science classrooms. The KidWind Challenge, a student driven renewable energy design competition.

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Inquiry based lab to explore how biofuels are created

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In this activity, students examine how to grow plants the most efficiently. They imagine that they are designing a biofuels production facility and need to know how to efficiently grow plants to use in this facility. As a means of solving this design problem, they plan a scientific experiment in which they investigate how a given variable (of their choice) affects plant growth. They then make predictions about the outcomes and record their observations after two weeks regarding the condition of the plants' stem, leaves and roots. They use these observations to guide their solution to the engineering design problem. The biological processes of photosynthesis and transpiration are briefly explained to help students make informed decisions about planning and interpreting their investigation and its results.
This engineering curriculum meets Next Generation Science Standards (NGSS).

Learning Objectives

After this activity, students should be able to:

Use vocabulary related to plants energy processes, including photosynthesis and transpiration.

Plan an investigation to support their design project.

Discuss the effect that an experimental variable (of their choice) has on plant growth.

Apply their understanding of plant growth to design a biofuels plant.

Educational Standards
Suggest an alignment not listed above

Materials List

Each group needs:

2 planting containers; e.g., plastic cups

6 seeds (e.g., lima beans, peas, broad beans, etc.)

2 cups soil

a glass bottle or jar

options for experimental variables (e.g., 2 different kinds of soil, fertilizer, sunlight filters, heat lamps)

one copy of the Designing a Biofuels Plant Worksheet for each student

one copy of the Corn for Fuel?! Datasheet for each student

To share with the entire class:

a dark area and a bright area - a box will work for the dark area

a glass bottle or jar

computer access, with an internet connection to watch an online video

Introduction/Motivation

Environmental engineers design products that are friendly to the Earth. Today we are going to design a way to provide energy for cars without using environmentally harmful fossil fuels. What are some possible alternative energy sources we could use? (Possible answers: solar, wind, hydropower, nuclear, or biomass) Okay, let's focus on solar power. Some engineers have worked on creating cars that use solar panels that generate electricity to power the car. Unfortunately, it's hard to get enough energy out of those solar panels to provide the kind of power that we typically use on ordinary cars. Does anyone have another idea for how we could harness the sun's energy to use in a car? I'll give a hint: it uses a natural way of storing the sun's energy, and we can put it into the car just like gasoline. The answer is biofuels!

Biofuels are a renewable form of fuel that biochemical engineers have created. These engineers figured out a way to turn the starch and sugar of corn and other plants into fuel called ethanol. With current technology, ethanol can only be made from the edible part of corn. However, biochemical engineers are currently trying to find a way that we can also use the nonedible parts, such as the husks. This would be a great way to use all of the biomass that is left over after we harvest the corn.

Figure 2. From photosynthesis to biofuel for cars?

Now, you may be wondering what this has to do with solar energy. Well, a plant is basically just nature's version of the photovoltaic cells that make up a solar panel. As you learned in the previous lesson, the plant converts solar energy into chemical energy that can be stored through a process called photosynthesis. The chlorophyll in the plant leaves use the sun's energy to turn carbon dioxide and water into glucose and oxygen. Later, in a biorefinery, the glucose is turned into ethanol, which provides the chemical energy that your car uses.

In this activity, you explore how to get the best results from growing plants. Your understanding of photosynthesis helps you understand your results. At the end of the activity, you will apply the information you gather to a biochemical engineering problem related to making biofuels.

Vocabulary/Definitions

biofuel: Fuel derived from biological sources; common examples are ethanol, which comes from the starch and sugar of plants (usually corn), and biodiesel, which combines alcohol with a fat, such as recycled frying oil.

fossil fuel: Fuel derived from the decomposed remains of plants and animals that lived over 300 million years ago.

photosynthesis: The process of using energy in sunlight to convert water and carbon dioxide into carbohydrates and oxygen.

transpiration: Water vapor that is emitted by a plant when it exchanges oxygen for carbon dioxideFossil Fuel and Plants Background

Procedure

Fossil Fuel and Plants Background

Fossil fuels are derived from the decomposed remains of plants and animals that lived over 300 million years ago (before the time of dinosaurs). Natural gas, coal and oil are the three main types of fossil fuels. About 85% of the energy used in the United States comes from fossil fuels. Because our supply of fossil fuels is limited, they are considered nonrenewable sources of energy.

The parts of a plant, similar to the body parts of a human, each have a function in order to help plants to attain the necessities of survival, food water and sunlight. The main components of the plant are the roots, the stem/trunk, branches and the leaves. The pores on the leaves of the plant are called the stomata, and they are the parts of the plants that take in sunlight. Plants begin their lives as seeds, which turn into roots. They eventually expand to leaves, flowers and even fruit, in many cases, to complete a cycle. Plants make their own food using the chlorophyll inside the cells of the leaves. Plants get their energy through a chemical process called photosynthesis. Sunlight reacts with the chlorophyll molecules in the leaves, creating Adenosine Triphosphate (ATP), a high-energy molecule, that is the chemical powerhouse that provides the energy to turn carbon dioxide and water into glucose. The glucose is the plant's "food." A byproduct of photosynthesis is oxygen, which is released into the atmosphere. See the associated lesson for this activity to learn more about photosynthesis.

Before the Activity
Day 1
1. Divide students into groups of 3-4.

2. Explain to students that they will be biochemical engineers today, designing a biofuels production facility to convert corn to ethanol. Explain that, like real engineers, they will use an iterative "design loop" to invent a biofuels facility. Handout the Designing a Biofuels Plant Worksheet, and point out that they will start with defining the problem. First, however, it is helpful to have some background information, which they can find in a video produced by the National Renewable Energy Laboratory (http://www.nrel.gov/learning/re_biofuels.html). As they watch the video, encourage students to think about what they would need to know to design a biofuels (ethanol) facility.

3. After watching the video, have students complete the first part of the Designing a Biofuels Plant Worksheet, where they write down what they would need to know in order to make a facility that would create ethanol. They can revise the list that they made during the Pre-Assessment.

4. After a few minutes, explain that today's design problem will focus on how to grow the most corn possible for their biofuels production facility. To gather information about this design problem, students will plan a controlled experiment with plants. As a result of this investigation, they should learn what conditions result in the greatest plant growth so that they can apply these findings to their engineering design problem. In addition, provide two different species of plant so that students can see how different species of plant can respond differently to the same environmental factors. Give the students another minute to write down an investigating question. On the back of their paper, they should write down their control and experimental groups. It may help to give them a list of some of the equipment you have that allows them to create varying growing conditions (e.g., two different kinds of soil, fertilizer, sunlight filters, heat lamps.)

Distribute different species to different groups so that the groups can compare their results to determine whether one growing condition affected one plant species more than the other. For instance, two groups can have sunlight as their experimental variable, but each group can test a different species of plant. With this approach, each group can not only draw conclusions about the impact on sunlight on growth for their particular plant species; they can also compare their results to determine if one plant species responded more strongly to changes in sunlight than the other. Alternatively, students could keep all of the growing conditions constant, and vary the species of plant.

Note: If they have never done this before, it may help to have them fill in the blanks for a prepared question (e.g., "How does ________ affect how the plants grow?). Examples to fill in could include "sunlight," "water," "soil composition," etc. The control and experimental groups should be consistent with their question. For example, if they choose sunlight, then the control group should be in the sun, and the other plants should be in the dark.

Check student's answers before they continue. You could have groups write their questions and control/experimental groups on the board, and give feedback as a class, so that everyone gets more practice with these investigation skills.

5. Once their investigation plans have been approved, have each group plant their seeds for both their control and experimental groups. Ideally, each group will have 6 seeds each, so that they can plant 3 control plants and 3 experimental plants for repeatability of results. Inform students they will keep track of the plant growth for each plant using the Corn for Fuel?! Datasheet.

6. As a closure activity for the day, have students write down their hypothesis for this experiment on separate sheet of paper. Collect their Designing a Biofuels Plant Worksheet.

7. Gather the class back together for a simple, short demonstration. Take a seedling that has been set aside for this demonstration, and place it in a bright place. Place a clear bottle or jar, turned upside down, on top of it. Explain that over the next week, they should look at the plant and observe what happens to the jar. Overnight, condensation should collect on the inside of the bottle or jar. This is the water vapor that is emitted by the plant when it exchanges oxygen for carbon dioxide - called transpiration. Start the next class (1 week later) by returning to this demonstration.
End of Day 1`
For the next week: Keep the seeds in their respective places for a week, or slight longer, watering them when the soil gets dry. If water was the experimental variable for the group, water according to their plan.
Day 2 (1 week later)
1. As a whole class, observe the demonstration plant that had the jar over it. Point out that they should see evidence of transpiration. Ask students to explain to their group what transpiration is and what evidence they see that it occurred. Gather the class back together to share their answers.

2. Give Designing a Biofuels Plant Worksheets back to students. Have them compare the seeds from the control and experimental group. Ask students to record what they see under the "observations" section of their worksheet. Next, students should separate one seedling away from each container and compare the root systems. Again, have the students record what they see on the observations section of their worksheet.

3. Have students measure the plant growth for each plant and record their results in the Corn for Fuel?! Datasheet.

4. Have a class discussion on the reasons for the observed differences in growth, above and below soil. Ask the class to tell what they know about photosynthesis. Use their responses to explain photosynthesis. (Basic definition: Plants use light to make food for themselves.)

5. Students should draw conclusions from their observed results and write down how they think they could apply this result to design a biofuels production plant.

6. Hold a class discussion for each group share their results and discuss how what they have learned could be applied to the design project. The Post-Activity Assessment has students return to the design problem to find a solution.

Worksheets and Attachments

Assessment

Pre-Activity Assessment

Define the Problem: If you were an engineer designing a biofuels refinery, you would need to know where to plant your crops to get the greatest yield of corn to turn into ethanol. With your group, make a list of things that you think you could do to grow your corn the most efficiently. (If students get stuck, ask them probing questions, like "Where would you plant your corn?" "What part of the country do you think would be the best place to grow your corn? Why?" "How important will water be for your corn production?" "Will different species of corn grow differently under the same environmental conditions?")

Activity Embedded Assessment

Research & Investigation: Use the provided worksheet to have students record their hypothesis, method, observations, and conclusions for the investigation. They should also record how they think their experiment could be applied to the engineering design problem of building a biofuels production plant.

Post-Activity Assessment

Designing a Biofuels Plant Worksheet: Using the results of their experiment, have students complete the design process loop on the front of their Designing a Biofuels Plant Worksheet.

First, they should brainstorm ideas for how to build a biofuels refinery plant that would turn corn into ethanol. The ideas should be focused on the topic of how to grow the most corn possible for their biofuels plant, based on what they learned from their experiment. Remind students that in brainstorming, no idea or suggestion is "silly." All ideas should be respectfully heard. Encourage wild ideas and discourage criticism of ideas.

After brainstorming ideas, they should study the ideas, and choose the best one(s). This idea should be a solution to the engineering problem of how to grow the most corn possible for ethanol production. Have each group share their ideas with the class.

Corn for Fuel?! Datasheet: Using the results of their experiment, have students graph their data and answer the questions on their Corn for Fuel?! Datasheet.

Activity Scaling

For upper grades, study the chemical reaction that takes place with ethanol production. Have them plan for how to handle the inputs and outputs of this reaction in their biofuels refinery design.

For lower grades, define the investigation problem for the students. A good choice would be: "How does sunlight affect plant growth?" You could then have a class discussion about how to plan the method. Each group should then perform the same experiment, which would include placing half the plants in sunlight, and the others in the dark.

References

Benyus, Janine M. Biomimicry: Innovation Inspired by Nature. New York. 1997.

U.S. Department of Energy, Energy Information Administration, Energy Kids Page, Energy Facts, "BIOMASS -- Renewable Energy from Plants and Animals," November 2007. www.eia.gov/kids/index.cfm Accessed March 5, 2009.

U.S. Department of Energy, Joint Genome Institute, "Bioenergy," June 27, 2008. www.jgi.doe.gov/education Accessed March 30, 2009.

Contributors Christopher Valenti; Karen King; Janet Yowell

Copyright © 2009 by Regents of the University of Colorado.

Supporting Program Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder

Acknowledgements

The contents of this digital library curriculum were developed under a grant from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation GK-12 grant no. 0338326. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.

Last modified: August 17, 2018

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In this activity, students examine how to grow plants the most efficiently. They imagine that they are designing a biofuels production facility and need to know how to efficiently grow plants to use in this facility. As a means of solving this design problem, they plan a scientific experiment in which they investigate how a given variable (of their choice) affects plant growth.

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Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

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Racing with the Sun - Creating a Solar Car - Activity

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Students use engineering design principles to construct and test a fully solar powered model car. Several options exist, though we recommend the "Junior Solar Sprint" (JSS) Car Kits that can be purchased with direction from the federal government. Using the JSS kit from Solar World, students are provided with a photovoltaic panel that produces ~3V at ~3W.

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Topics

Description

Play with a bar magnet and coils to learn about Faraday's law. Move a bar magnet near one or two coils to make a light bulb glow. View the magnetic field lines. A meter shows the direction and magnitude of the current. View the magnetic field lines or use a meter to show the direction and magnitude of the current. You can also play with electromagnets, generators and transformers!

Sample Learning Goals

Predict the direction of the magnetic field for different locations around a bar magnet and an electromagnet.

Compare and contrast bar magnets and electromagnets.

Identify the characteristics of electromagnets that are variable and what effects each variable has on the magnetic field's strength and direction.

Relate magnetic field strength to distance quantitatively and qualitatively.

Identify equipment and conditions that produce induction.

Compare and contrast how both a light bulb and voltmeter can be used to show characteristics of the induced current.

Predict how the current will change when the conditions are varied.

Teacher Tips

Overview of sim controls, model simplifications, and insights into student thinking ( PDF ).

Video Primer

Teacher-Submitted Activities

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Play with a bar magnet and coils to learn about Faraday's law. Move a bar magnet near one or two coils to make a light bulb glow. View the magnetic field lines. A meter shows the direction and magnitude of the current.

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Building motors- Scaffolding Lesson Background

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Building motors- Scaffolding Lesson Background

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Here is a great site that describes how DC motors work. http://www.howstuffworks.com/motor.htm There are several types of basic DC motors you can build. They make super science fair projects.

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In the future, all of us will own flying cars. Oh, wait -- that's "The Jetsons." Our views of future transportation are a little more realistic, but cars will increasingly use electric power, reducing our dependence on fossil fuels. Right?

That outcome is by no means certain. In fact, there are some mechanically-inclined people who think that the way of the automotive future lies in another direction entirely: steam-powered engines. And though it might sound a bit antiquated, it's less dated than one might imagine.

Powering a vehicle with steam isn't so much an innovation as it is revisiting an old idea. Plans for steam-powered vehicles date as far back as the 17th century. Around 1672, a Flemish Jesuit named Ferdinand Verbiest drew up the specs for a very small steam-propelled vehicle (possibly a toy) while living at the Imperial Chinese court. There's little evidence to suggest that Verbiest ever built the vehicle, but a better-documented first attempt is that of Nicolas-Joseph Cugnot in 1769. His steam-powered carriage was slow and quickly ran out of steam (literally), but it still marked a breakthrough in transportation.

Innovations in steam power continued throughout the 19th century. By the time automobiles starting becoming commonplace on city streets, steam-powered cars were one of the options. The Stanley Motor Carriage Company produced steam vehicles that were affectionately known as Stanley Steamers or Flying Teapots. They were very popular in the early 1900s, but it soon became cheaper and more efficient to purchase what is now the norm for commercial automobiles -- a car with an internal combustion engine. This means that fuel is burned inside the engine, and the explosion from the burning gasoline results in the pressure necessary to turn the moving parts of the engine. In contrast, steam-powered engines work by external combustion, which means that a fuel source is required outside the engine to produce the steam that propels the moving parts. Thus far, internal combustion engines have proven themselves to be physically smaller and more fuel-efficient than their external cousins.

But that might be changing. A handful of mechanically-inclined tinkerers and entrepreneurs have set out to build more efficient steam engines. Some, like the B ritish Steam Car Team, seem to be in it for the challenge and fun. Then there's Harry Schoell, whose company, Cyclone Power Technologies, has produced a steam-driven automotive engine that might actually convince consumers to give water vapor power a try. While the steam engines of the past have been large and unwieldy, Schoell's engines would fit easily into the footprint of a standard internal combustion engine.

So what's different? Schoell's design is built on a closed-loop system of heating and cooling, which makes the engine much more efficient and produces less waste than previous models. The steam gets so hot that it behaves more like a liquid, which yields more power. It's also less expensive to produce and maintain because it doesn't need a catalytic converter, muffler, oil or a transmission like an internal combustion engine. But best of all, in this era of fossil fuel anxiety, you can use any fuel you like to kick-start the steam process, whether that's gasoline from petroleum or biofuel.

But will steam-powered engines be used on large scale? Read on to learn more.

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Is there a future for steam-powered, super-efficient cars?

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In the future, all of us will own flying cars. Oh, wait -- that's "The Jetsons." Our views of future transportation are a little more realistic, but cars will increasingly use electric power, reducing our dependence on fossil fuels. Right?

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Building a solar-powered car will introduce your students to alternative energy concepts while incorporating problem-solving, design, and modeling. In addition, students will experience using hand tools as they construct their solar vehicle.

Make Your Own Solar Car

Adult supervision is recommended for this project.

What You Need for a Solar Car Project

Small electric motor (Look at hobby or electronics stores, and make sure you get one with a motor pulley)

For the car body: cardboard milk carton, water bottle, cardboard, foam board, or similar materials

For the front wheels and back wheels: plastic bottle caps, film canister caps, toy wheels such as K'nex, etc.

For the axles: Stiff wire or wooden shish-kabob skewers

Straws or eye screws to mount the axles

How to Build a Solar-Powered Car

1. Choose a material for the car body, which is called the chassis. Think carefully about this: you want something strong, but also something lightweight so it needs less power for the motor to move it. (But be careful - if it's too light, it can easily get blown about by the wind.) A big part of engineering is finding the right balance between weight and strength.

2. Use a nail to poke a small hole in the center of your wheels. Make sure the stiff wire or wooden skewers you use for axles fit in the holes tightly. Take an extra cap and cut off the sides, leaving just the top part, which usually has a small inner rim to help keep the bottle from leaking. Glue this cap to one of your wheels. You have just created a pulley for your driving wheel; the inner rim of the extra bottle cap will support your car's drive belt. (You can try using a film canister cap for this step instead of cutting a bottle cap. If you are using toy wheels like K'nex, you can just use a smaller wheel mounted on the inside of your main wheel to act as the pulley.)

3. Now, mount your axles onto the chassis. Depending on what your chassis is made of, you can thread the axle through eye screws mounted on the bottom. Another easy method is to tape straws on the underside of the chassis and threads the axles through them. (Use our balloon rocket car project as a reference for how to do this.)

4. Attach the small motor pulley to the motor shaft. Determine where to mount the motor by connecting the driving pulley with the motor pulley using an elastic band as a drive belt. Position the motor so the band is slightly stretched (but don't stretch it too much!). Mount the motor with glue or tape it in between a small frame of wood or cardboard blocks.

5. Use clear plastic tape to attach the two solar cells together side-by-side; then connect them in a series circuit using the alligator clip leads. Connect the positive terminal of one cell to the negative terminal of the other. Connect the remaining terminals to the motor. If the motor spins the wrong way, switch the leads where they connect to the motor. Once it's connected properly, you'll probably want to use tape to help keep the wires under control.

6. Mount the solar cells on the chassis at an angle where they will receive the most sun. Take your car outside to a sunny sidewalk, connect the drive belt, and watch it go!

7. Designing and building a car from scratch involves a lot of perseverance and trial and error, so don't be discouraged if yours doesn't work perfectly right away. Experiment to see if you can improve the design of your solar car. How fast does it go? Does it drive straight? How would it perform with only one solar cell? What if you used smoother wheels for less friction? Keep testing new ideas to make your car work better.

Once you've perfected your car, think about other ways you could experiment with solar power.

Could you build a solar boat or water pump?

Maybe you'll be the next scientist to help find out!

For more solar science fun, check out these science projects:

Solar Power Science Lesson

The Sun: The Ultimate Power Source

Every morning the sun rises, bringing light and heat to the earth, and every evening it sets. It seems so commonplace that we rarely spare a thought for that bright object in the sky. Yet without it, we wouldn't exist!

Deep in the core of our local star, hydrogen atoms react by nuclear fusion, producing a massive amount of energy that streams in all directions at the speed of light (that's the mind-boggling speed of more than 186,000 miles per second). In just eight minutes, that energy travels 93 million miles to earth.

We use many different forms of energy here on earth, but here's the thing: almost all of them originate with the sun, not just light and heat (thermal) energy!

The law of conservation of energy says that energy can't be created or destroyed, but can change its form. And that's what happens with energy from the sun -it changes into lots of different forms:

Plants convert light energy from the sun into chemical energy (food) by the process of photosynthesis. Animals eat plants and use that same chemical energy for all their activities.

Heat energy from the sun causes changing weather patterns that produce wind. Wind turbines then convert wind power into electrical energy.

Hydroelectricity is electrical energy produced from moving water, and water flows because heat energy from the sun causes evaporation that keeps water moving through the water cycle.

Right now, much of human activity uses energy from fossil fuels such as coal, oil, and natural gas. These energy sources are created over very long periods of time from decayed and fossilized living matter (animals and plants), and the energy in that living matter originally came from the sun through photosynthesis.

The sun sends more energy to the earth in one hour than the whole planet needs in a year. Imagine if we could capture that energy directly and convert it to a form that could power our cities, homes, and cars!

Many scientists around the world are researching how we can improve our use of the sun's energy. One way is to use solar thermal panels to collect thermal energy to heat air and water.

Another way is to use photovoltaic (PV) cells, also called solar cells, to convert sunlight directly into electricity. ('Photovoltaic' essentially means 'light electricity'.)

PV cells use a material such as silicon to absorb energy from sunlight. The sunlight energy causes some electrons to break free from the silicon atoms in the cell.

Because of how the solar cell is made, these free electrons move to one side of the cell, creating a negative charge and leaving a positive charge on the other side.

PV cells today are still only able to capture a small fraction of the sun's energy, so acres of them are necessary to collect enough light to create electricity on a large scale.

A lot more scientific work needs to be done to make them more efficient and take up less space. Despite the challenges, solar panels are used to power many things such as emergency signs, school crossing lights, and more.

Many people are also able to power their homes by mounting solar panels on the roof, and this will only get easier as the technology continues to advance.

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Building a solar-powered car will introduce your students to alternative energy concepts while incorporating problem-solving, design, and modeling. In addition, students will experience using hand tools as they construct their solar vehicle. Adult supervision is recommended for this project.

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How electric vehicles work :: GARFIELD CLEAN ENERGY

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Advanced battery technology is common in modern hybrid and electric vehicles, including nickel-metal hydride and lithium-ion batteries. Regardless of which chemistry is chosen for use in an electric vehicle, the result is the same: electrochemical reactions produce voltage and current, which are harnessed by an electric motor to move the vehicle.

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Turning Goo to Fuel - Hydrothermal Liquefaction at Pacific Northwest National Laboratory

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Alternative Fuels Data Center: Alternative Fueling Station Locator

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Find More places to share Alternative Fuels Data Center: Alternative Fueling Station Locator on AddThis.com...

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Alternative Fuels Data Center Calculator

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Alternative Fuels Data Center Calculator

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Alternative Fuels Data Center: Vehicle Cost Calculator

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Send a link to Alternative Fuels Data Center: Vehicle Cost Calculator to someone by E-mail

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There are many forms of renewable energy . Most of these renewable energies depend in one way or another on sunlight.

Wind and hydroelectric power are the direct result of differential heating of the Earth's surface which leads to air moving about (wind) and precipitation forming as the air is lifted. Solar energy is the direct conversion of sunlight using panels or collectors.

Biomass energy is stored sunlight contained in plants. Other renewable energies that do not depend on sunlight are geothermal energy, which is a result of radioactive decay in the crust combined with the original heat of accreting the Earth, and tidal energy, which is a conversion of gravitational energy.

Solar. This form of energy relies on the nuclear fusion power from the core of the Sun. This energy can be collected and converted in a few different ways. The range is from solar water heating with solar collectors or attic cooling with solar attic fans for domestic use to the complex technologies of direct conversion of sunlight to electrical energy using mirrors and boilers or photovoltaic cells. Unfortunately these are currently insufficient to fully power our modern society.

Wind Power. The movement of the atmosphere is driven by differences of temperature at the Earth's surface due to varying temperatures of the Earth's surface when lit by sunlight. Wind energy can be used to pump water or generate electricity, but requires extensive areal coverage to produce significant amounts of energy.

Hydroelectric energy. This form uses the gravitational potential of elevated water that was lifted from the oceans by sunlight. It is not strictly speaking renewable since all reservoirs eventually fill up and require very expensive excavation to become useful again. At this time, most of the available locations for hydroelectric dams are already used in the developed world.

Biomass is the term for energy from plants. Energy in this form is very commonly used throughout the world. Unfortunately the most popular is the burning of trees for cooking and warmth. This process releases copious amounts of carbon dioxide gases into the atmosphere and is a major contributor to unhealthy air in many areas. Some of the more modern forms of biomass energy are methane generation and production of alcohol for automobile fuel and fueling electric power plants.

Hydrogen and fuel cells. These are also not strictly renewable energy resources but are very abundant in availability and are very low in pollution when utilized. Hydrogen can be burned as a fuel, typically in a vehicle, with only water as the combustion product. This clean burning fuel can mean a significant reduction of pollution in cities. Or the hydrogen can be used in fuel cells, which are similar to batteries, to power an electric motor. In either case significant production of hydrogen requires abundant power. Due to the need for energy to produce the initial hydrogen gas, the result is the relocation of pollution from the cities to the power plants. There are several promising methods to produce hydrogen, such as solar power, that may alter this picture drastically.

Geothermal power. Energy left over from the original accretion of the planet and augmented by heat from radioactive decay seeps out slowly everywhere, everyday. In certain areas the geothermal gradient (increase in temperature with depth) is high enough to exploit to generate electricity. This possibility is limited to a few locations on Earth and many technical problems exist that limit its utility. Another form of geothermal energy is Earth energy, a result of the heat storage in the Earth's surface. Soil everywhere tends to stay at a relatively constant temperature, the yearly average, and can be used with heat pumps to heat a building in winter and cool a building in summer. This form of energy can lessen the need for other power to maintain comfortable temperatures in buildings, but cannot be used to produce electricity.

Other forms of energy. Energy from tides, the oceans and hot hydrogen fusion are other forms that can be used to generate electricity. Each of these is discussed in some detail with the final result being that each suffers from one or another significant drawback and cannot be relied upon at this time to solve the upcoming energy crunch.

Can A Country Achieve 100% Renewable Energy?
If you think 100% renewable energy will never happen, think again. Several countries have adopted ambitious plan to obtain their power from renewable energy. These countries are not only accelerating RE installations but are also integrating RE into their existing infrastructure to reach a 100% RE mix. Read our article..
What are renewable energy sources? Solar power can be used directly for heating and producing electricity or indirectly via biomass, wind, ocean thermal, and hydroelectric power. Energy from the gravititational field can be harnessed by tidal power; and the internal heat of the Earth can be tapped geothermally.

These tools and more can help make the transition from non-renewable to renewable and environmentally friendly energy. However, none of these is sufficiently developed or abundant enough to substitute for fossil fuels use. Every one of these power sources (with the exception of hydroelectric) has low environmental costs, and combined have the potential to be important in avoiding a monumental crisis when the fossil fuel crunch hits. These energy sources are often non-centralized, leading to greater consumer control and involvement.

However, currently each of these energy forms is significantly more expensive than fossil fuels, which will lead to economic dislocations and hardship if they become the only power source for the future.

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There are many forms of renewable energy . Most of these renewable energies depend in one way or another on sunlight. Wind and hydroelectric power are the direct result of differential heating of the Earth's surface which leads to air moving about (wind) and precipitation forming as the air is lifted.

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Just hit the "+" button in the bottom right hand corner.