BP'S Aberdeen office was recently on the receiving end of a Greenpeace protest, when activists scaled the Dyce building to put solar panels on the roof.

If they had really wanted to make an impact, perhaps they should have climbed onto the Houses of Parliament. Evidence from Germany suggests that a little bit of government support goes a long way.

In 1991, the German authorities decided to encourage solar power with a DmlOOm subsidy designed to get 2,500 households to install photovoltaic panels. Astonishingly, 66,000 householders appplied.

Since then, a scheme had been introduced under which Germans can receive a premium rate of Dm2 per kWh produced by their own solar panels and fed into the national grid.

As a result, the market for solar panels has soared, with sales rising by 25% last year. Interestingly, it is a market where BP has quarter share.