BBC: The think-tank IPPR has warned the UK Chancellor not to use green taxes to plug the hole in government finances. Its new research shows that government could gain £3.5bn a year through a carbon tax on homes and vehicles. But IPPR says this would harm the poor unless ministers give back all the cash in the form of benefits, tax breaks and home insulation. A government source insisted that increased green taxes did have a role to play in future. The left-leaning …