A government task force is seeking views on the relative merits of energy taxation versus emissions trading to reduce greenhouse gasses from industry. The group is headed by Sir Colin Marshall, chairman of British Airways and president of the Confederation of British Industry. It was set up by Gordon Brown, Chancellor of the Exchequer, to look at the use of economic instruments to help the UK meet its domestic target of a 20% reduction in CO2 by 2010. In a consultation paper, the group narrowed the options down to two: an emissions trading scheme and a tax -- either on industrial or commercial use of energy or on the carbon content of fuel. But Marshall stresses that revenues raised from either option must be put back into business to ensure fiscal neutrality. The group wants responses by the end of July and expects to report to the Treasury by November.