A £14 million library has been voted the Building of the Year in an "ethical living" awards scheme.

The Observer newspaper's Ethical Awards panel of judges, including Hollywood actor Woody Harrelson, celebrity gardener Monty Don and Ali Hewson, who is married to U2's Bono, said Brighton's Jubilee Library was the clear winner.

The panel said: "It deserves the award because it uses leading edge technology to reduce the environmental burden and functions really well using solar warmth, natural light and sea breezes.

"It has regenerated the area and sets a very positive example. It will be seen by a lot of people and has the potential to be replicated."

Brighton's library opened last March and its low-energy building design quickly drew plaudits for innovations such as lights that automatically switch on when it gets dark and toilets that flush with rainwater. In October the library beat off competition from 14 other buildings to win the Prime Minister's Award for Better Public Buildings.

The deputy leader of Brighton and Hove City Council, Sue John, was in London last night to receive the prize.

The library also beat competition in its category from St Pancras School in Lewes. Its new arts building has used environmentally benign materials that are sourced locally.