California boosts renewable power use

California has committed itself to producing one fifth of all retail electricity from renewable sources by 2017, the highest proportion in the US.

State governor Gray Davis signed legislation in September requiring utilities to increase their output from wind, geothermal, biomass and solar sources by at least 1% a year to a minimum of 20% by the 2017 deadline.

California currently produces about 10% of its electricity from non-hydroelectric renewable sources, according to state figures.

A spokesw