A novel British satellite is set to go into orbit later on Monday, designed to map the heat signature of buildings.
The idea is to highlight those dwellings that are wasting energy and could benefit from better insulation.
The relatively small spacecraft is called, appropriately, HotSat-1; and will be operated by the London-based start-up Satellite Vu.
Its infrared sensor has been developed with funds from the UK and European space agencies.
HotSat-1 is due to launch on a SpaceX Falcon-9 rocket from the Vandenberg Space Force Base in California at 14:19 PDT (22:19 BST).
Flying at an altitude of 500km (311 miles), it will have the resolution to see individual roof tops and walls.
The UK has some of the most inefficient housing stock in Europe, with the vast majority of dwellings built pre-1970.