Energy bills are likely to rise twice as fast as the government forecasts this decade because households are not buying new efficient appliances that are supposed to save them money, a new report warns on Wednesday. Ministers claimed last year that energy bills would rise by £64 over the rest of the decade – from £1,267 in 2013 to £1,331 in 2020. It said that the costs of green subsidies would be partially offset by consumers using less energy as they trade in old fridges, TVs and lights for new efficient models. But new analysis by centre-left think tank IPPR for campaign group Global Action Plan finds that bills are likely to increase by a further £63, because consumers will buy fewer efficient products than expected. Slow roll-out of regulation, confusing product labelling and consumers saving their cash after the economic downturn are all likely to result in savings from product efficiency being 40pc less than the £158 that the government had forecast, it found.