Earth Day 2010: The world’s most powerful solar power tower

Thursday, 22nd April 2010 by

Today is Earth Day, the mission of which is to "broaden and diversify the environmental movement worldwide". Inspired by an excellent post over at the Google Earth Blog, today we're going to visit the Planta Solar 20 – the world's most powerful solar power tower.

The PS20 solar power tower is a solar thermal energy plant near the sunny Spanish city of Seville. It has a power capacity of 20 megawatts - which is enough to provide energy for around 10,000 homes.

The plant only opened in April last year, so unfortunately it doesn't yet appear on Google's aerial or satellite photography - but it has been captured by the Spanish Street View driver, who manages to get quite a good view of the 165m tower.

The plant uses 1,255 large movable mirrors called heliostats to track the movement of the sun, which focus the sun's rays back at a receiver mounted on the central tower.

Water pumped up the tower and through the receiver boils into steam, which is then directed through a turbine to produce electricity.

There are actually two towers here - the PS10 tower (opened in 2007) was the world's first commercial solar power tower plant. The 115m tower uses 624 mirrors to produce around half the energy of PS20.

Unfortunately it costs around twice as much to produce electricity via concentrating solar power as it does from fossil fuels, but we can do our part (wherever possible) by voting with our wallets.

There's some more great Earth day sightseeing links at the Google Earth Blog, and there's a good article about the PS20 tower at Venturebeat.