Experience from hybrid heat pumps, which use smart controls to manage domestic heat by using a heat pumps and ‘topping up’ heat from a conventional boiler, is that they can halve energy bills and play a large role in decarbonising the grid, according to trial results. Policymakers now have to take decisions on how to inform customers about the need to decarbonise heat and develop an incentive regime that will allow them to bear the higher upfront costs of the technology.