Breakthrough in solar panel manufacture promises cheap energy within a decade

Technical advance based on edible salt overcomes need to use toxic agents

Science Editor

A breakthrough in the production of solar cells will make the next generation of solar panels cheaper and safer, and promises to accelerate the development of solar energy over the next decade, scientists said.

A technical advance based on an edible salt used in the manufacture of tofu could revolutionise the production of future solar panels to make them less expensive, more flexible and easier to use than the current models seen on millions of roofs across Britain.

Researchers believe they have found a way of overcoming one of the most serious limitations of the next generation of solar panels, which are based on toxic cadmium chloride, by simply adding magnesium chloride, an abundant salt found in seawater.

A study has shown that the solar cells produced with magnesium chloride – which is also found in bath salts as well as used to coagulate soya milk into tofu – work just as efficiently as conventional cadmium cells but at a fraction of the cost and with much lower toxicity.

“We certainly believe it’s going to make a big change to the costs of these devices. The cost of solar is going to match fossil fuels eventually but this is going to get us there quicker,” said Jon Major of the University of Liverpool, who led the research.

“Magnesium chloride is incredibly low-cost and it’s simply recovered from seawater. It’s used to de-ice roads in winter and it’s completely harmless and non-toxic. We’ve managed to replace a highly expensive, toxic material with one that’s completely benign and low cost,” Dr Major said.

About 90 per cent of the solar panels currently in use are made of photovoltaic cells composed of silicon semiconductors, which convert sunlight directly into electricity. However, silicon is not good at absorbing sunlight which is why the next generation of PV cells will be based on a thin coating of cadmium telluride, which absorbs sunlight so well that it only needs to be about one hundredth of the thickness of silicon.

However, although cadmium telluride is seen as the future for solar energy, it is potentially dangerous after it is “activated” with cadmium chloride, a critical step in the manufacturing process that raises the efficiency of converting sunlight to electricity from about two per cent to 15 per cent or more.

The Liverpool team attempted to find an alternative to cadmium chloride in the activation step and discovered that it could be done just as well with magnesium chloride, which they sprayed onto a test sample of cadmium telluride with a model aircraft spray gun they bought for £49.99, Dr Major said.

In a study published in the journal Nature, the researchers demonstrated that the efficiency of the resulting photovoltaic cells made from cadmium telluride and magnesium chloride were on a par with commercial cadmium telluride cells that had been activated with toxic cadmium chloride.

“We have to apply cadmium chloride in a fume cupboard in the lab, but we created solar cells using the new method on a bench with a spray gun bought from a model shop,” Dr Major said.

“Cadmium chloride is toxic and expensive, and we no longer need to use it. Replacing it with a naturally occurring substance could save the industry a vast amount of money and reduce the overall cost for generating power from solar,” he said.

It is not possible to estimate how much cheaper the new solar cells will be, Dr Major said, but magnesium chloride is about one per cent of the cost of cadmium chloride. In addition, waste disposal will be far easier and cheaper with a product based on a non-toxic salt, he said.

Asked why the solar power industry had not thought of using magnesium chloride before, Dr Major said: “We genuinely don’t know. The only reason we can suggest is that cadmium chloride works well so it may be a case of ‘if it’s not broke, why is there a need to fix it?’”

Jeremy Leggett, chairman of the renewable energy firm Solarcentury, said that the development is exciting because it promises to make an already competitive industry even more competitive with conventional sources of energy, such as fossil fuels.

“Their costs are coming down so fast that they are already knocking the business models of utilities into what some analysts call a ‘death spiral’. Imagine, then, what will happen if developments such as the one described in the new research come to market,” Dr Leggett said.

Start your day with The Independent, sign up for daily news emails
News
Johnny Depp is perhaps best known for his role as Jack Sparrow in Pirates of the Caribbean
peopleBut how did he break it?
Arts and Entertainment
Paul Walker and Vin Diesel in Fast and Furious 5
film
Sport
Lewis Hamilton secured his second straight pole of the season
f1Vettel beats Rosberg into third after thunderstorm delays qualifying
ebooks
ebooksA special investigation by Andy McSmith
  • Get to the point
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Massage Therapist / Sports Therapist

£12000 - £24000 per annum: Recruitment Genius: A opportunity has arisen for a ...

Ashdown Group: Practice Accountant - Bournemouth - £38,000

£32000 - £38000 per annum: Ashdown Group: A successful accountancy practice in...

SThree: Trainee Recruitment Consultant

£18000 - £23000 per annum + Uncapped commission: SThree: Does earning a 6 figu...

Recruitment Genius: SEO Executive

£18000 - £25000 per annum: Recruitment Genius: This is an exciting opportunity...

Day In a Page

The saffron censorship that governs India: Why national pride and religious sentiment trump freedom of expression

The saffron censorship that governs India

Zareer Masani reveals why national pride and religious sentiment trump freedom of expression
Prince Charles' 'black spider' letters to be published 'within weeks'

Prince Charles' 'black spider' letters to be published 'within weeks'

Supreme Court rules Dominic Grieve's ministerial veto was invalid
Distressed Zayn Malik fans are cutting themselves - how did fandom get so dark?

How did fandom get so dark?

Grief over Zayn Malik's exit from One Direction seemed amusing until stories of mass 'cutting' emerged. Experts tell Gillian Orr the distress is real, and the girls need support
The galaxy collisions that shed light on unseen parallel Universe

The cosmic collisions that have shed light on unseen parallel Universe

Dark matter study gives scientists insight into mystery of space
The Swedes are adding a gender-neutral pronoun to their dictionary

Swedes introduce gender-neutral pronoun

Why, asks Simon Usborne, must English still struggle awkwardly with the likes of 's/he' and 'they'?
Disney's mega money-making formula: 'Human' remakes of cartoon classics are part of a lucrative, long-term creative plan

Disney's mega money-making formula

'Human' remakes of cartoon classics are part of a lucrative, long-term creative plan
Lobster has gone mainstream with supermarket bargains for £10 or less - but is it any good?

Lobster has gone mainstream

Anthea Gerrie, raised on meaty specimens from the waters around Maine, reveals how to cook up an affordable feast
Easter 2015: 14 best decorations

14 best Easter decorations

Get into the Easter spirit with our pick of accessories, ornaments and tableware
Paul Scholes column: Gareth Bale would be a perfect fit at Manchester United and could turn them into serious title contenders next season

Paul Scholes column

Gareth Bale would be a perfect fit at Manchester United and could turn them into serious title contenders next season
Inside the Kansas greenhouses where Monsanto is 'playing God' with the future of the planet

The future of GM

The greenhouses where Monsanto 'plays God' with the future of the planet
Britain's mild winters could be numbered: why global warming is leaving UK chillier

Britain's mild winters could be numbered

Gulf Stream is slowing down faster than ever, scientists say
Government gives £250,000 to Independent appeal

Government gives £250,000 to Independent appeal

Donation brings total raised by Homeless Veterans campaign to at least £1.25m
Oh dear, the most borrowed book at Bank of England library doesn't inspire confidence

The most borrowed book at Bank of England library? Oh dear

The book's fifth edition is used for Edexcel exams
Cowslips vs honeysuckle: The hunt for the UK’s favourite wildflower

Cowslips vs honeysuckle

It's the hunt for UK’s favourite wildflower
Child abuse scandal: Did a botched blackmail attempt by South African intelligence help Cyril Smith escape justice?

Did a botched blackmail attempt help Cyril Smith escape justice?

A fresh twist reveals the Liberal MP was targeted by the notorious South African intelligence agency Boss