With solar energy usage on the increase globally, it's predicted a third of all new electricity production installed each year will be PV by 2015

Solar energy has cemented its place as the world’s fastest-growing energy source with global production of photovoltaic cells (PV) standing at 3,800 megawatts last year. Manufacture was up 50% over 2006.

“The exponential growth in PV production is a result of PV becoming cost effective as a distributed electricity generation option,” said Travis Bradford, of US-based non-profit, the Prometheus Institute for Sustainable Development, which originated the figures.

“By 2015, a third of all new electricity production installed globally each year could be PV, climbing quickly from there. Within the next 30 years, PV will become the cheapest way to provide electricity to nearly every user in the world.”

PV production has been doubling every year since 2002, spurred by a reduction in the price of the modules from $100 (£50.44) per watt in 1975 to $4 (£2.01) at the end of 2006.

This has been driven by new, thin-film, minimising the slowing effects of a global shortage of polysilicon, the traditional material used for solar cells. Other materials, such as cadmium telluride are deposited in thin layers on glass or plastic. The technology is less efficient but cheaper to manufacture.

Catching up

But solar power has a long way to go to catch up with fossil fuels. Global energy consumption happens at a rate of 13-15 Terawatts (a million megawatts). In 2005 PV supplied just 0.04% of the world’s energy needs. Worldwide power usage rises an average of 2% annually.

Germany has vastly more installed solar power than any other European country with 750 MWp installed in 2006. France was next with just 50MWp, according to the European Photovoltaic Industry Association.

2007 saw a 35% increase in clean energy worldwide reaching $117 billion. The figure was $68 billion in 2006, according to New Energy Finance. Europe aims to get 20% of its power from renewable energy by 2020.