German firm, SolarWorld AG, has just donated approximately 2,000 solar modules to the Vatican to be installed on the Paul VI audience hall roof. The solar system will produce some 315,500 kilowatt-hours of power a year, offsetting some 315 tons of carbon dioxide emissions, it said.

That is a lot of solar panels - I estimate about 240 kilowatts of peak power - so this is no small donation, perhaps a million euros, although plenty of repeat publicity. If you look at this aerial map here of the Vatican - you can see why this building is a great site for solar power - a nice flat roof. And Rome of course, I can personally attest, is very hot in the summer.

Anyway, back to SolarWorld. Unusually among German solar companies it is vertically integrated, combining all stages of the solar value chain, from the raw material silicon to turn-key solar power plants. Moreover, the firm has a sizeable presence in Sweden and the USA. And I recommend looking at slide number 8 of one of their recent presentations; this forecasts a near quadrupling of solar production from 2090 MW in 2007 to 7619 in 2010. That is staggering growth, much faster than I was familiar with.