Business Green: The US Department of Energy (DoE) has this week once again opened up its stimulus funding war chest, announcing $256m (£155m) in fresh investment for energy-efficiency projects and a further $50m of funding for geothermal heat pump technologies. The energy-efficiency funding, which has been made available through the American Recovery and Reinvestment Act, will be targeted at projects designed to improve energy efficiency across heavy industries and the IT and communications …