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UK firm's solar power breakthrough could make world's most efficient panels by 2021 | Business | The Guardian

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British rooftops could be hosting a breakthrough in new solar power technology by next summer, using a crystal first discovered more than 200 years ago to help harness more of the sun's power.

An Oxford-based solar technology firm hopes by the end of the year to begin manufacturing the world's most efficient solar panels, and become the first to sell them to the public within the next year.

Oxford PV claims that the next-generation solar panels will be able to generate almost a third more electricity than traditional silicon-based solar panels by coating the panels with a thin layer of a crystal material called perovskite.

The breakthrough would offer the first major step-change in solar power generation since the technology emerged in the 1950s, and could play a major role in helping to tackle the climate crisis by increasing clean energy.

By coating a traditional solar power cell with perovskite a solar panel can increase its power generation, and lower the overall costs of the clean electricity, because the crystal is able to absorb different parts of the solar spectrum than traditional silicon.

Typically a silicon solar cell is able to convert up to about 22% of the available solar energy into electricity. But in June 2018, Oxford PV's perovskite-on-silicon solar cell surpassed the best performing silicon-only solar cell by reaching a new world record of 27.3%.

The perovskite-coated panels will appear different too. Instead of the blue tint usually associated with traditional silicon panels, Oxford PV's panels will appear black and blend in better with rooftop slates.

The mineral perovskite, also known as the crystal calcium titanate, was first discovered by a Russian mineralogist in the Ural mountains in 1839. In the last 10 years, scientists around the world have been locked in a race to engineer chemical compounds based upon the perovskite crystal structure but that are able to generate more renewable electricity at a lower cost.

Dr Chris Case, the chief technology officer at Oxford PV, said using perovskite represents "a true change" for solar technology, which has remained relatively unchanged since the silicon-based panels developed in the 1950s.

"Silicon has reached its culmination of capability," he said. "There are residual improvements to be made, and cost of production opportunities, but from a performance standpoint it is at its efficiency limit. The perovskite material is something totally innovative for solar."

The company won £100,000 of funding from the UK government in 2010, before attracting equity investment from Norwegian oil giant Equinor, Legal & General Capital and the Chinese renewables giant Goldwind.

Frank Averdung, Oxford PV's chief executive, said the company will be able to steal a march on the first commercially available solar panels which use perovskite to improve solar generation against the company's rivals.

"There are other companies working on perovskite, of course, and these other companies will eventually have a commercial focus, but none of these companies has the same focus on the combination of silicon and perovskite which we do," he said.

* This article was amended on 19 August 2020 to better describe perovskite.

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UK firm's solar power breakthrough could make world's most efficient panels by 2021

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British rooftops could be hosting a breakthrough in new solar power technology by next summer, using a crystal first discovered more than 200 years ago to help harness more of the sun's power.

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Video | In a Nutshell

3. Three Reasons Why Nuclear Energy is Awesome

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3 Reasons Why Nuclear Energy Is Awesome! 3/3

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Video | In a Nutshell
2. Three Reasons why Nuclear Energy is Terrible

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3 Reasons Why Nuclear Energy Is Terrible! 2/3

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Video | In a Nutshell
1. How does it work

This video gives a short history of nuclear power

You don't need to know about the details of nuclear fission and fusion until  Unit 4

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Nuclear Energy Explained: How does it work? 1/3

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Video | My GCSE Science

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GCSE Physics National and global energy resources (AQA 9-1)

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Apple | CGP

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Apple | CGP

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This amazing revision App will test your Physics knowledge in one-minute bursts! The free version includes one topic to get you started, and you can upgrade to full course coverage for just £1.99.

* Hundreds of quick-fire questions - all perfectly matched to the AQA GCSE Physics course
* Snack-sized 60-second tests - it's your brain versus the ticking clock. Good luck!
* Every answer fully explained - so it's simple to check anything you got wrong
* Win sparkly trophies - and post them on social media to impress people on the internet

After all that practice, you'll be at the top of your game when the exams arrive.

Version 1.0.5

Ok, but.....

It's good having the questions there, but why do the tests have to be timed? Having 60 seconds to answer as many questions as possible is a poor way to judge someone's knowledge on a subject. Just have 'x' amount of questions for each test which randomise. I also think it would be much more useful if you could also sign in (if you have an online account), making it possible to look through the material you have purchased. Having it all in one place would be so useful when travelling. The books are great!!

It's fine

It's a good concept, but if the questions weren't timed it would be a lot more helpful.

The god awful update I wish I hadn't of installed...

Beforehand, this app was a virtual book where you could flick to pages in the revision guide and read. (This is handy if you lose or forget your revision guide) Now however, it is a quiz game that you have to pay £1.99 for and it does not contain any pages of the revision guide. Very disappointed...

Ah, you're thinking of the Online Editions of our Revision Guides - these quiz-based GCSE Science Apps are completely separate! If you had a CGP Online Edition on your device, you should still be able to access it via your CGP online account. Drop us an email at customerservices@cgpbooks.co.uk if you're having any problems.

Information

Provider

Coordination Group Publications Limited

Compatibility

Requires iOS 8.0 or later. Compatible with iPhone 5S, iPhone 6, iPhone 6 Plus, iPhone 6S, iPhone 6S Plus, iPhone SE (1st generation), iPhone 7, iPhone 7 Plus, iPhone 8, iPhone 8 Plus, iPhone X, iPhone XS, iPhone XS Max, iPhone XR, iPhone 11, iPhone 11 Pro, iPhone 11 Pro Max, iPhone SE (2nd generation), iPad Air, iPad Air Wi‑Fi + Cellular, iPad mini 2, iPad mini 2 Wi‑Fi + Cellular, iPad Air 2, iPad Air 2 Wi‑Fi + Cellular, iPad mini 3, iPad mini 3 Wi‑Fi + Cellular, iPad mini 4, iPad mini 4 Wi‑Fi + Cellular, iPad Pro (12.9‑inch), iPad Pro (12.9‑inch) Wi‑Fi + Cellular, iPad Pro (9.7‑inch), iPad Pro (9.7‑inch) Wi‑Fi + Cellular, iPad (5th generation), iPad (5th generation) Wi‑Fi + Cellular, iPad Pro (12.9‑inch) (2nd generation), iPad Pro (12.9‑inch) (2nd generation) Wi‑Fi + Cellular, iPad Pro (10.5‑inch), iPad Pro (10.5‑inch) Wi‑Fi + Cellular, iPad (6th generation), iPad Wi‑Fi + Cellular (6th generation), iPad Pro (11‑inch), iPad Pro (11‑inch) Wi‑Fi + Cellular, iPad Pro (12.9‑inch) (3rd generation), iPad Pro (12.9‑inch) (3rd generation) Wi‑Fi + Cellular, iPad mini (5th generation), iPad mini (5th generation) Wi‑Fi + Cellular, iPad Air (3rd generation), iPad Air (3rd generation) Wi‑Fi + Cellular, iPad (7th generation), iPad (7th generation) Wi‑Fi + Cellular, iPad Pro (11‑inch) (2nd generation), iPad Pro (11‑inch) (2nd generation) Wi‑Fi + Cellular, iPad Pro (12.9‑inch) (4th generation), iPad Pro (12.9‑inch) (4th generation) Wi‑Fi + Cellular, iPod touch (6th generation) and iPod touch (7th generation).

Copyright

© 2019 Coordination Group Publications Ltd

In-App Purchases

GCSE Physics Premium Unlock £1.99

Family Sharing

Up to six family members will be able to use this app with Family Sharing enabled.

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‎This amazing revision App will test your Physics knowledge in one-minute bursts! The free version includes one topic to get you started, and you can upgrade to full course coverage for just £1.99. * Hundreds of quick-fire questions - all perfectly matched to the AQA GCSE Physics course * Snack-si...

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Video | 5 Minute Physics

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GCSE Science: Physics: Energy resources - renewables

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Video | 5 Minute Physics

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GCSE Science: Physics: Energy resources - fossil fuels and turbines

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Video | Cognito

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GCSE Physics - Hydroelectricity and Tidal Barrage  #13

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Video | Cognito

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Video | Cognito

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Video | Cognito

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Video | Cognito

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GCSE Physics - Introduction to Energy Sources  #9

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Sample Exam Questions on Energy

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Multiple choice questions are perhaps the easiest to complete - you simply put a cross in a box - however, the questions often have two answers that could, at first glance, be correct. Don't make the mistake of reading the first answer and thinking this is correct without checking all the others.

If it says 'Tick box', you must tick one box. If you leave it blank or tick two or more boxes you will get zero marks. These multiple choice questions will not start with command words like 'describe' or 'explain'. They will be written in the form of a question like 'What...?' or 'Why...?'.

There will be more multiple choice questions on the Foundation paper.
This page contains AQA material which is reproduced by permission of AQA.

Sample question 1 - Foundation

Energy resources that involve burning fuels such as coal, oil, natural gas or biomass release pollutants into the atmosphere. This includes large amounts of carbon dioxide. Carbon dioxide contributes to the greenhouse effect and global warming.

Sample question 2 - Foundation

An island has a large number of wind turbines and a coal-fired power station.

The island needs to use the electricity generated by the coal-fired power station at certain times.

Wind turbines only generate electricity when it's sufficiently windy. Reliable energy resources such as coal-fired power stations are required to generate electricity when the output from wind turbines is low.

Sample question 3 - Foundation

What name is given to the total kinetic energy and potential energy of all the particles of helium gas in a helium balloon?

Particles vibrate, and have kinetic energy. There is also potential energy stored in the bonds between them. These two energy stores combined are known as internal energy.

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Sample exam questions - Energy - AQA - Revision 1 - GCSE Combined Science - BBC Bitesize

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Multiple choice questions are perhaps the easiest to complete - you simply put a cross in a box - however, the questions often have two answers that could, at first glance, be correct. Don't make the mistake of reading the first answer and thinking this is correct without checking all the others.

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Energy Demands

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Nearly everything requires and a way to use energy is by transferring it from one to another.

Systems that can store large amounts of energy are called . The major energy resources available to produce electricity are , , bio-fuel, wind, , , tidal, water waves and the Sun. Ultimately, all the energy on Earth originally comes from the Sun but has been stored as different energy resources.

Energy is needed in:

homes - for cooking, heating and running appliances

public services, eg schools and hospitals - running machinery and warming rooms

factories and farms - operating heavy-duty machines and production chains

transport - buses, trains, cars and boats all need a fuel source and some trains and trams connect to an electricity supply

However, producing and distributing electricity can cause damage to the environment. Releasing energy from some stores causes pollution and harmful waste products. Burning fossil fuels releases carbon dioxide, adding to the greenhouse effect, and sulphur dioxide which causes acid rain.

Patterns and trends in use of energy resources

During the Industrial Revolution , advances in automation and transport caused a significant increase in the amount of fossil fuels extracted and burnt.

In the 20th century, electricity became a convenient way of distributing energy. This powered a wide range of devices and applications such as lighting, heating, computing technologies and operating machinery.

Demand for energy varies with the time of year and the time of day. During early evening a lot of energy is needed for heating, lighting and cooking but overnight there is very little needed while people sleep. During winter there is more heating and lighting required than in summertime.

Global energy consumption

Most of the electricity generated globally is still produced by fossil fuels. This is partly due to:

the high power output fossil fuels give compared to other energy resources, like wind and water waves

the existing for extracting, transporting and processing fossil fuels - this makes fossil fuels cheaper than setting up new alternatives

The recognised impact on the environment of burning fossil fuels has caused science and society to develop the use of energy resources and make machines more efficient.

In some countries, nuclear power stations are a growing form of electricity generation. Nuclear fuel can release large amounts of energy compared to fossil fuels and does not emit carbon dioxide. However, the radioactive waste that is produced is difficult to store and dispose of.

Other factors that could influence governments' decisions about the use of energy resources are political and economic pressures. For example, countries where the economy is heavily based on extracting and exporting oil, have a strong interest in fossil fuels to be largely used in electricity generation. In order to compete with more developed countries, growing countries like China need a large power output to keep growing their industry. This means they are likely to continue using fossil fuels and developing the use of nuclear power, alongside increasing supply from renewable sources of energy.

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National and global energy demands and resources - Energy demands - AQA - GCSE Combined Science Revision - AQA Trilogy - BBC Bitesize

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Nearly everything requires and a way to use energy is by transferring it from one to another. Systems that can store large amounts of energy are called . The major energy resources available to produce electricity are , , bio-fuel, wind, , , tidal, water waves and the Sun.

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Sample Exam Questions on Energy

# data[].attributes.attachment_link.readable_text
Multiple choice questions are perhaps the easiest to complete - you simply put a cross in a box - however, the questions often have two answers that could, at first glance, be correct. Don't make the mistake of reading the first answer and thinking this is correct without checking all the others.

If it says 'Tick box', you must tick one box. If you leave it blank or tick two or more boxes you will get zero marks. These multiple choice questions will not start with command words like 'describe' or 'explain'. They will be written in the form of a question like 'What...?' or 'Why...?'.

There will be more multiple choice questions on the Foundation paper.
This page contains AQA material which is reproduced by permission of AQA.

Sample question 1 - Foundation

Energy resources that involve burning fuels such as coal, oil, natural gas or biomass release pollutants into the atmosphere. This includes large amounts of carbon dioxide. Carbon dioxide contributes to the greenhouse effect and global warming.

Sample question 2 - Foundation

An island has a large number of wind turbines and a coal-fired power station.

The island needs to use the electricity generated by the coal-fired power station at certain times.

Wind turbines only generate electricity when it's sufficiently windy. Reliable energy resources such as coal-fired power stations are required to generate electricity when the output from wind turbines is low.

Sample question 3 - Foundation

What name is given to the total kinetic energy and potential energy of all the particles of helium gas in a helium balloon?

Particles vibrate, and have kinetic energy. There is also potential energy stored in the bonds between them. These two energy stores combined are known as internal energy.

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Sample exam questions - Energy - AQA - Revision 1 - GCSE Physics (Single Science) - BBC Bitesize

# data[].attributes.attachment_link.description
Multiple choice questions are perhaps the easiest to complete - you simply put a cross in a box - however, the questions often have two answers that could, at first glance, be correct. Don't make the mistake of reading the first answer and thinking this is correct without checking all the others.

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Energy Demands

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Energy needs

Nearly everything requires and a way to use energy is by transferring it from one to another.

Systems that can store large amounts of energy are called . The major energy resources available to produce electricity are , , bio-fuel, wind, , , tidal, water waves and the Sun. Ultimately, all the energy on Earth originally comes from the Sun but has been stored as different energy resources.

Energy is needed in:

homes - for cooking, heating and running appliances

public services, eg schools and hospitals - running machinery and warming rooms

factories and farms - operating heavy-duty machines and production chains

transport - buses, trains, cars and boats all need a fuel source and some trains and trams connect to an electricity supply

However, producing and distributing electricity can cause damage to the environment. Releasing energy from some stores causes pollution and harmful waste products. Burning fossil fuels releases carbon dioxide, adding to the greenhouse effect, and sulphur dioxide which causes acid rain.

Patterns and trends in use of energy resources

During the Industrial Revolution , advances in automation and transport caused a significant increase in the amount of fossil fuels extracted and burnt.

In the 20th century, electricity became a convenient way of distributing energy. This powered a wide range of devices and applications such as lighting, heating, computing technologies and operating machinery.

Demand for energy varies with the time of year and the time of day. During early evening a lot of energy is needed for heating, lighting and cooking but overnight there is very little needed while people sleep. During winter there is more heating and lighting required than in summertime.

Global energy consumption

Most of the electricity generated globally is still produced by fossil fuels. This is partly due to:

the high power output fossil fuels give compared to other energy resources, like wind and water waves

the existing for extracting, transporting and processing fossil fuels - this makes fossil fuels cheaper than setting up new alternatives

The recognised impact on the environment of burning fossil fuels has caused science and society to develop the use of energy resources and make machines more efficient.

In some countries, nuclear power stations are a growing form of electricity generation. Nuclear fuel can release large amounts of energy compared to fossil fuels and does not emit carbon dioxide. However, the radioactive waste that is produced is difficult to store and dispose of.

Other factors that could influence governments' decisions about the use of energy resources are political and economic pressures. For example, countries where the economy is heavily based on extracting and exporting oil, have a strong interest in fossil fuels to be largely used in electricity generation. In order to compete with more developed countries, growing countries like China need a large power output to keep growing their industry. This means they are likely to continue using fossil fuels and developing the use of nuclear power, alongside increasing supply from renewable sources of energy.

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Energy demands - AQA - Revision 1 - GCSE Physics (Single Science) - BBC Bitesize

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Nearly everything requires and a way to use energy is by transferring it from one to another. Systems that can store large amounts of energy are called . The major energy resources available to produce electricity are , , bio-fuel, wind, , , tidal, water waves and the Sun.

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The Windscale Fire: Britain's 'Chernobyl' which was 'covered up' for decades

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(Image: PA)

Over 60 years ago, Britain flirted with a nuclear catastrophe that could have resulted in a tragedy worse than Chernobyl.

The Windscale Fire remains the UK's worst ever nuclear accident - but its chilling memory is mostly consigned to the history books.

A catastrophic meltdown was averted by the heroic actions of a few people but a subsequent 'cover up' by authorities meant they were not properly recognised for their efforts.

On October 10 1957, uranium fuel at the Windscale plant in Cumbria overheated and caught fire, setting in motion a terrifying series of events.

Windscale deputy general manager Tom Tuohy led the efforts that day and was tasked with trying to extinguish the unprecedented fire.

After kissing his family goodbye and telling to keep the windows closed, the 39-year-old rushed to the plant less than a mile from his home.

In an act of incredible bravery, Tuohy donned protective gear before climbing 80ft to the concrete shaft that sat atop of the Number 1 nuclear pile to get a better understanding of the situation.

To his horror, he peered down and saw an unusual red glow, revealing that uranium was burning at astronomically high temperatures inside.

The countdown to disaster

Earlier that week on October 7, Windscale workers were carrying out a procedure on the reactor's graphite core known as annealing.

Instead of cooling the reactor down, inaccurate temperature readings showed that the process had not been successfully completed and was put into action a second time - a decision that was to prove a terrible mistake.

Control rods were withdrawn, allowing the nuclear fission process to restart and causing the graphite within the reactor to rise to dangerously high temperatures.

It was only days later that staff became aware of the fire which had begun burning uranium.

Tom Hughes and another control room operator went to the charge face of the reactor wearing protective equipment and were astonished with their findings.

"We saw to our complete horror, four channels of fuel glowing bright cherry red", he recounted.

On Friday, 11 October, the fire had reached temperatures of up to 1,300 centigrade. Eleven tons of uranium were ablaze and the plant's workers were increasingly desperate.

"It was white hot, it was just white hot. Nobody, I mean, nobody, can believe how hot it could possibly be", one eyewitness would later say.

Tuohy and his team failed in their initial efforts to put out the conflagration as carbon dioxide did little to fan the flames.

Water was hosed onto the reactor core, again without success. The move was deemed highly risky which as it had the potential to cause an explosive reaction with molten metal.

Tuohy finally made the decision to shut off all cooling and ventilation systems to stop air from entering the building.

To their delight, this plan was enough to stave the fire of the oxygen that it needed and water was hosed through holes into the reactor

Over the next 24 hours the flames died down and eventually dwindled to nothing; the emergency was finally over.

The aftermath

A white paper into the incident - known as the Penney report - was published two weeks later but remained classified until 1988.

Windscale was home to the UK's atomic bomb project and secrecy shrouded the facility in the years of Cold War paranoia.

It had been hoped the United States was about to begin sharing its nuclear secrets with UK atomic agency scientists and it was thought that any embarrassing revelations about Windscale could put this at risk.

The report blamed "an error of judgement" by the Windscale workers for the crisis and Prime Minister Harold Macmillan ordered that it not be released to the public.

"He covered it up, plain and simple", says his grandson and biographer, Lord Stockton.

Unlike Cheronbyl, the site was used purely for military purposes and produced enriched uranium to be used for Britain's nuclear warheads.

Built in 1950 with the prior approval of Winston Churchill, it was hoped that the Windscale project could eventually help develop a chillingly destructive hydrogen bomb.

The British government officially estimates that up to 30 people developed thyroid cancer after hazardous radioactive waste polluted the surrounding countryside.

However, analysis revealed that a further 240 people may have died from cancers related to Windscale.

Iodine-131 and other harmful radioactive particles contaminated farms in the surrounding countryside and cow's milk was taken from a massive 500km area next to Sellafield.

It was diluted a thousand fold and dumped into the Irish Sea leaving it partially contaminated.

But radioactive pollution from the incident would have been far higher had it not been for the foresight of one man.

During Windscale's construction, physicist Sir John Cockcroft insisted that the plant be fitted with massive ugly, chimney stacks which would help filter out leaks.

They were installed at great expense and with long delays to the project and the towers were later dubbed "Cockcroft's Folly".

Only 20,000 curies of radioactive materials were released into the environment thanks to their presence - far less than at Chernobyl and Fukushima.

Once the Penney Report was finally published, some thirty years after the accident, the public were made aware of the full extent of the crisis.

The Board of Inquiry had lauded the efforts by the workers who "displayed considerable devotion to duty on the part of all concerned".

It may have taken decades, but the record had finally been put straight.

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Britain's 'Chernobyl' which was 'covered up' for decades

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Over 60 years ago, Britain flirted with a nuclear catastrophe that could have resulted in a tragedy worse than Chernobyl. The Windscale Fire remains the UK's worst ever nuclear accident - but its chilling memory is mostly consigned to the history books.

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Diagrams & labels | presentation

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AQA P1 | electricity generation | diagrams

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Create cinematic presentations, share them with a link, and collaborate with others in real time.

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UK goes a week without coal but the renewables revolution is stalling | New Scientist

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Should we be thrilled that the UK has gone a whole week without using coal to make electricity for the first time in a century? While some are welcoming it as a sign the UK is going green, the bigger picture is less encouraging.

For one thing, renewables supplied only 23 per cent of electricity during this coal-free week, with 45 per cent coming from natural gas. What's more, the UK is veering off track when it comes to meeting its long-term targets for cutting greenhouse gas emissions - as is the entire world.

The thing is, generating electricity without burning fossil fuels is relatively easy. It is much harder to heat homes, power cars, ships and planes, make cement and steel, and grow food without producing any greenhouse gases. So if we are struggling with the easy part, what chance do we have of doing the hard stuff?

Advertisement

Let's start with the UK. In the past decade, the country has gone from getting a third of its electricity from coal to getting more than a third from renewables, on average. Coal is expected to provide only 1 per cent of electricity this year and should be phased out by 2025.

That isn't not quite as brilliant as it seems. The UK is now getting 11 per cent of its electricity from biomass, much of it imported wood. Forest campaigners say swapping coal for wood isn't truly renewable and is doing huge damage to the environment.

Even the UK's own official adviser on climate change says large-scale electricity generation from biomass is a bad idea. Wood should be used for things like building, it says, so the carbon remains locked away.

What's more, the UK has now stopped most of the subsidies that drove its renewables revolution and continues to veto the cheapest form of renewable power, onshore wind. While renewables could provide half the UK's electricity within a decade, growth is expected to slow to a near halt by this time.

The global renewables revolution also seems to be stalling. On Monday, the International Energy Agency (IEA) announced that the world added 180 gigawatts of capacity of solar, wind, hydro and bioenergy in 2018, the same as in 2017. It says we need to add 300 gigawatts a year to have a chance of limiting warming to under 2°C by 2100.

"These 2018 data are deeply worrying, but smart and determined policies can get renewable capacity additions back on an upward trend," said Fatih Birol, the director of the IEA, in a statement.

There is some debate about the IEA figures. They include only new power production that has been verified and confirmed. By contrast, Bloomberg New Energy Finance includes estimates of unconfirmed additions, and it says that solar grew 10 per cent globally in 2018.

Nonetheless, that is still a slowdown compared with the growth rates of about 30 per cent seen in the past, says Jenny Chase, head of solar at Bloomberg. "But it's harder to grow a big number," she says.

This follows a separate report last year that said investment was falling in most countries, with the exception of China. Now China too is cutting back.

Many climate activists have promoted the idea that the falling costs of renewables will mean they inevitably take over from fossil fuels even without government help. But if electricity prices don't stay high enough, investors will take their money elsewhere. So we should cheer the end of coal - but continue to worry about how it will be replaced.

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UK goes a week without coal but the renewables revolution is stalling

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Should we be thrilled that the UK has gone a whole week without using coal to make electricity for the first time in a century? While some are welcoming it as a sign the UK is going green, the bigger picture is less encouraging.