Radiant heat is invisible light.  In the same way that lights are sited to light a room, Herschel Infrared heaters emit heat to directly warm the walls, floor and ceiling of a building (the ‘thermal mass’). Once the thermal mass is warm, the building itself retains the heat for a period of time, so the heater only needs to be on to top up.

Most of other forms of heaters are convection heaters which primarily heat volumes of air, which then has to transfer its heat to the building in order to warm the thermal mass. The problem is that hot air rises to the ceiling (where you don’t want it) and easily escapes with draughts and open doors. The direct transfer of heat to the building is why Herschel is more efficient and saves energy compared to convection heating.

It also more comfortable because you don’t have cold floors and stuffy air.

Convective heat sources only heat the air and not the environment. Air has a lower ability to transfer thermal energy to a surface and warm the environment, radiant heat has a higher rate of heat transfer per kilowatt than convection, so you need less of it. This results in a lower kW requirement and lower running times and is why infrared heating saves energy.

Infrared offers high levels of thermal comfort at lower air temperatures. When total costs of ownership of a heat pump versus infrared heating are considered over the lifetime of the heating (purchase, installation, running, maintenance, replacement) infrared presents a very compelling picture.