Guardian: Supermarket group Tesco, which pumps out some four million tonnes of carbon a year, today opened its first zero carbon store as part of its bid to be a carbon neutral company by 2050. The shop, in Ramsey, Cambridgeshire, is timber-framed rather than steel, and uses skylights and sun pipes to cut lighting costs. It also has a combined heat and power plant powered by renewable bio-fuels, exporting extra electricity back to the national grid. In addition the refrigerators – one of the …