But things may not go according to plan. The energy we generate and consume ultimately ends up being dissipated into the environment as heat. This input is relatively small today but might become significant in the next century, Cowern and Ahn suggest.

Their calculations show that if global energy use increases at about 1 per cent per year – slower than in the recent past – then by 2100, the heat dissipated could become significant enough to cancel out the benefits of cuts in emissions