If we do look back and see this time as when the solar energy really ignited it will also speak volumes to the billions in wasted funds by governments trying to play favorites with technologies that may have led to delays in finding technology that actually works.


"Cheap, abundant solar power from Britain's grey skies? Don't mock, this is one dream that could soon be a reality"

Materials scientists have been exploring other semiconductor technologies for a long while, trying to find something cheaper and better than silicon. Until recently the best bet was dye-sensitised solar cells. These have been around since the 1980s, but they have not managed to make a big impact on the energy market because, although they are cheap because they don't require billion-dollar clean-room facilities, their efficiency is generally low. This is where the new perovskite solar cells come in. There are exotic-sounding compounds, such as methylammonium trihalogen plumbates, that have a quite simple crystal structure called a perovskite. Like the dye-sensitised solar cells, these solar cells are easy and cheap to make, but they have another trick up their sleeve – they don't need a complicated diode architecture to achieve high efficiencies.

Materials researchers in Oxford, led by Dr Henry Snaith, have recently shown that they can make simple perovskite solar cells with efficiencies pushing 20%. This is big news, because 20% makes them competitive with existing commercial silicon solar cells while being much cheaper to make in high volumes. They are also more suitable for incorporating into roofing materials and glass panels than silicon and so have the clear potential of being as fundamental to our city architecture as steel, concrete and asphalt. In other words, they could well be the materials that will make it possible to collect the 1% of solar energy we need as a nation, at a cost that can compete with fossil fuels.

Hearing research results such as this makes you grudgingly admit conferences are worth going to, and indeed gets you wondering whether we might look back in 10 years and pinpoint this as the time the solar energy revolution really ignited. One of my industry colleagues believes so; after the talk he immediately Skyped his research group, told them to stop what they were doing and get working on perovskite solar cells. The race to commercialise them is on.