This article compares the various types of electric space heating.
==All types=A few things apply to all of them.
All electric heaters are 100% efficient, none of the heat goes outdoors.
All are exempt from the annual inspections required of gas appliances in rented properties.
==Plug in heaters==These are all much more expensive to run than all other mainstream heating options, at around 3-4x the energy cost of mains gas.
Thermostatic models prevent room overheating, which wastes money & energy.
Plug-ins are best suited to just occasional use, where their high run cost and zero installation cost makes sense.
==ún heater==High energy cost, usually fairly high power, fast heating, small, noisy, fire risk if covered.
===Convector==High energy cost, medium power, medium size, no noise, less fire risk if covered.
===Electric Radiator==High energy cost, lowish power, slow, large. Some only reach a moderate temperature, and are touch safe, no fire risk, and can be used to dry clothes. Some get hot enough to burn things though. Relatively good around kids and the infirm, though they're heavyish and can be knocked over. More tolerant of minor water spills than most other portable heater types. Some have a radiator temperature control, some don't.
==ºr fire==These radiate heat from a red hot bar. Older models tend to be dangerous, with an exposed red hot live bar, inadequate guarding, and they tend to catch fire if something falls on them. They also seem to attract naughty kids that like to experiment. New models have improved guarding, but no other benefit.
Replacement heating bars are available if one fails, but a better heater is usually preferable.
===Halogen heater==A more modern version of a bar fire, these use a red halogen lamp in place of the bare bar. The lamp is insulated rather than bare & live. The heat density isn't as high (400w per bar is typical), reducing the fire risk.
The halogen lamps last far longer than visible light lamps, but they don't last forever. Replacement infra red lamps are available.
===Tubular heater==Tubular heaters are low power (typically from 60w to 300w) and low power density heaters designed to remain safe if a coat etc falls on them. These are used where items might fall on them, for pipe freeze protection, to keep frost off greenhouses, etc. The safest of all plug- in heater types. More tolerant of minor water spills than most other portable heater types.
==Heat pump=There's only one type of electric heating that can beat 100% efficiency, and that's a heat pump. These can give equivalent to 300% efficiency by using the leccy to pump heat in from outdoors. Since all heat pumps take heat from outdoors, they must be installed one way or another.
===Air source heat pump==Air source heat pumps are the cheapest heat pump. These use a coil and fan to extract heat from the outdoor air.
The downside of air source heat pumps is that efficiency and hence energy delivery falls as outdoor temp falls. When the outdoor coil freezes, which happens somewhere in the region of 5C and below, efficiency drops much further, making them ineffective heaters at such times.
Sometimes the units are reversable, also able to operate as air conditioning in summer.
===Ground source heat pump==The downsides of ground source heat pumps are that a huge and costly layer of ground tubing needs to be laid. This takes a large area of ground.
===Geothermal source heat pump==The downside is installation cost: a bore hole must be drilled, and a long heat source tube lowered into the water in it. These use less than a square foot of land.
==Storage heaters=These heat up a pile of firebricks overnight on cheap rate electricity (using economy 7 & similar schemes). During the day the stored heat is let out by controlled flaps.
The main downside of storage heating is poor controllability, poor weather prediction, and sometimes they run out of heat before recharging time. Some newer models access weather forecasts in a bid to improve performance, how successful this is I don't know.
Storage heaters are bulky compared to radiators.
Storage heating is the second cheapest method of electric heating to run (only heat pumps cost less), and its suitable for all weathers, making it one of the most common choices. The run cost is still significantly higher than mains gas.
Note that daytime rates are often slightly higher on E7 type schemes, so the savings tend not to be quite as good as they appear.
==Under floor heating=UFH is available in piped water and electric forms. The electric version is much more expensive to run.
The main advantages of UFH are that no heating equipment is visible, and it provides a comfortable warm floor. The warmth is especially appreciated with a tiled floor, and in bathrooms.
When installed on a ground floor it requires [[insulation]] underfloor. Usually this means taking up the existing floor, but there are thin insulation boards that allow heating to be laid on top of an existing floor.
UFH can't usefully be powered by cheap rate electricity. UFH has a significant time lag, so must be timed to turn on before the heat is needed. For these reasons, electric ufh is inherently not a cheap option. Heating cable failure can occsaionally happen, and this creates additional expense if the floor is tiled or otherwise permanently finished.
Pipe based ufh driven by the central heating boiler is preferred wherever this is usable, as its much cheaper to run, and more reliable long term.
==Halogen radiant=Wall mounted halogen radiant heaters produce radiant heat plus red light. The principle is exactly the same as halogen plug-in heaters, and their shortcomings the same. They bneed to be mounted high up to reach all areas of the room, and the amount of red light given out at near eye level can cause some visual discomfort. For this reason they tend to see more use in commercial spaces.
==Obsolete=Obsolete types of electric heating are still occasionally encountered.
==Îiling radiant heat==Ceiling mounted radiant heaters are occasionally seen in 1960s properties. Since heat rises, these give poor performance, with rooms cold at the floor and hot near the ceiling. This increases energy use and losses.
===Bowl heater==These were popular from the 1920s to 50s, but are rarely seen today. These are economical radiant heaters for use in cold houses, as more of the radiant heat is directed to the person sitting nearby, compared to a bar fire. Usually rated at a few hundred watts, these are intended to take the chill off an otherwise unheated space.
They have all the defects of bar fires, plus instability, which increases the fire risk further. Also their age makes them generally fail to meet even basic electrical safety standards. They have little chance of passing a PAT test and should not be used.
==See Also=* [[Insulation]] * [[Heating]] * [[Special:Allpages|Wiki Contents]] * [[Special:Categories|Wiki Subject Categories]]