Leaf fuel could help save planet

Researchers from Glasgow University are trying to create a special kind of leaf that is able to produce liquid fuel. If it works, the invention could help to slow down climate change.

Normal leaves take energy from the sun and turn it into food in a process called photosynthesis. The special leaf would take solar energy, as well as electricity, and turn it into fuel instead.

When we burn fossil fuels, like oil, carbon dioxide (CO2) is released into the atmosphere. When leaves photosynthesis, they use up CO2. If people burned the fuel produced by the special leaves, the carbon dioxide would be released again but it would not add extra CO2 to the air in the way that burning oil does.

Burning petrol produces carbon dioxide, a greenhouse gas

The 'leaf' that the scientists want to make won't actually look anything like a real leaf. Instead, it will consist of a tank full of water containing genetically-modified bacteria. But the system will work in a similar way to natural photosynthesis in plants.

"The sun gives its energy away for free but making use of it is tricky," said Professor Richard Cogdell, who is in charge of the project.

We can use solar panels to make electricity. We can also use turbines to trap energy from wind and waves. But electricity can't be stored. Professor Codgell's team think their 'leaves' would give us a way to bottle up the sun's energy so that we can use it whenever we need it. The new technology may be ready in about five years.

How are we tackling climate change?

Billions of pounds are spent every year on attempts to find ways to reduce greenhouse gases and slow down climate change. Special 'leaves' that use a process similar to photosynthesis to create a carbon-neutral fuel is just one of the latest.

Although greenhouse gas emissions in the UK have fallen by more than a quarter since 1990, what happens in our country is only a tiny part of the global picture.

In 2010 the world's emissions of CO2 rose by almost 6%, the biggest increase ever recorded, largely because more coal was burned in China and India. According to a UN report, carrying on at this rate will leave the world a massive 12 gigatonnes of carbon short of needed reductions by 2020.

Global CO2 emissions rose 6% in 2010, mainly due to countries burning more coal

The United Nations climate talks in Durban, South Africa, late last year ended in a deal committing countries to sign up to a treaty on cutting carbon emissions by 2015.

It is the first time that major polluters the USA, China and India have signed up to a process that will result in a legally-binding agreement to cut their emissions.

But critics say that the deal is too little too late - the treaty would not come into effect until 2020.

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