Hydrocarbon 'fuel' photosynthesising

An oil substitute made with 'artificial leaf' technology could power ships and planes, according to a leading British expert.

Scientists have applied a new twist to the process of photosynthesis - the method plants use to harness the energy of sunlight.

Instead of producing organic material from carbon dioxide, as plants do, they plan to manufacture a hydrocarbon 'fuel' which could be used instead of oil, using photosynthesising bacteria.

The scientists hope to prove the technology in the next two years and to develop a small-scale demonstration system within five.

This has been tried before, with little success.

But just recently the University of Glasgow team had a 'eureka moment' - the discovery that the process could be driven by electricity instead of light.

The oil would be used to 'store' energy which could then power vehicles.

Professor Richard Cogdell, who heads the research, believes the greater efficiency this achieves could make the technology a major energy source in decades to come.

Speaking at the annual meeting of the American Association for the Advancement of Science (AAAS) in Vancouver, Canada, he said: 'The big issue at the moment is that most renewable energy sources make electricity. That's fine, but we have not good ways of storing electricity, and it's intermittent.

'What you need is to be able to lock that energy up in some sort of storage fluid that's available on demand, and that's what fuel is.

'To really sustain our way of life after the oil runs out we have to be able to make, renewably and sustainably, dense portable fuels for transport, especially for aeroplanes and ships.

'We're looking at photosynthesis to see whether we can learn to copy it in a more robust and efficient way.

'What we've realised in just the last couple of months is that we should be able to use electricity to power these reactions.

Prof Cogdell envisages power stations containing vats of bacteria churning out large quantities of burnable fuel. The bugs would break down carbon dioxide in a potentially carbon-neutral process, and might even help reduce levels of the greenhouse gas in the atmosphere.

Solar panels could provide some of the electricity needed, thereby simulating true photosynthesis.

Prof Cogdell hopes to prove the technology in the next two years and to develop a small-scale demonstration system within five.

He added: 'I would be very disappointed if this wasn't working in the real world in 30 years time.'

The aim is to modify cyanobacteria, which contain all the necessary machinery for photosynthesis, so they can power themselves with electricity rather than sunlight.

This would involve modifying them using genes from another bacterium that draws electricity using a wire-like growth called a pilus.


Normally the bug, geobacter, extracts electricity from minerals. But it can also tap current from an electrode, the Glasgow scientists have learned.

Modified to behave the same way, cyanobacteria would 'connect' themselves to a power source.

'If the dream is fulfilled we'd have vats of cyanobacteria connected to electrodes,' said Prof Cogdell. 'A current would come in and that would power them to convert carbon dioxide into hydrocarbons.'

The project has already received strong government backing with around £3 million in grants.

'This is real blue skies research,' Prof Cogdell added. 'We may fail, but it's important that we try.'