Guardian: Despite all the media attention on wind, solar and even wave power as key sources of renewable energy, the UK’s largest green energy provider is biomass – using wood, annual crops or waste materials as fuel for heat and electricity. It now generates over 2% of our total electricity, enough to power more than 2m homes. In addition, it produces about 1% of heat for our homes and industry. And it has the potential to deliver even more in the future, helping the UK to meet its target of …