Everything about Storage Heater totally explained
A
storage heater is an electrical
appliance which stores
heat at a time when
base load electricity is available at a low price, usually during the night, and releases it during the day. Heat is usually stored in
clay bricks or other
ceramic material because of its low cost and high
specific heat capacity. In Australia, electric storage heaters are often referred to as 'heat banks'.
Storage heaters are usually used in conjunction with a
two-tariff electricity meter which records separately the electricity used during the off-peak period so that it can be billed at a lower rate. In order to derive any benefit from a storage heater, the house must be on a special electricity tariff. In the United Kingdom, the
Economy 7 tariff is appropriate.
Storage heaters usually have two controls - a charge control (often called "input"), which controls the amount of heat stored, and the draught control (often called "output"), which controls the rate at which heat is released. These controls may be set by the user, or in some models are automatic and allow you to set the target room temperature using a thermostat.
Many units also contain a conventional electric heater which can be used to give a boost in heat output during the day. If this feature is relied upon too much, a lot of peak time electricity will be used and the storage heater will prove expensive to run.
Storage heaters have several drawbacks:
- If insufficient heat has been stored, for example if there's an unexpected period of cold weather, then any extra heat needed will have to be produced using full-price electricity.
- If too much heat has been stored, then sooner or later the heat will be released into the room whether it's needed or not.
- Storage heaters are very heavy and somewhat bulky, due to the material used to store heat.
- Unless the heater is of the modern well-insulated type, heat is leaked out whenever the bricks are hot, meaning that having a room warm in the evening requires it to be warm all day (albeit probably at a lower setting), wasting energy (unless the room is in use all day as well). However, the consequences of this energy loss are often more than compensated for by the heater's use of an off-peak base load that's effectively "spare energy" and is cheap.
Storage heaters have declined in popularity due to these drawbacks and the low cost of
gas-fired
central heating. However, many new properties in the UK are built with storage heaters, and their inspection/maintenance costs are less than gas.
Using storage heaters
Storage heaters can be very cost-effective if used properly. However, understanding the heater's mode of operation and using the heater effectively throughout the year takes more thought and planning than a central heating system.
Power switches
Newer installations will provide two separate power circuits, one for on-peak and one for off-peak electricity, and two power switches on the wall next to each storage heater. These should be switched off during the summer when the operator doesn't require heat. During other months the off-peak switch can be left on at all times, with the on-peak switch being used when insufficient energy has been stored during off-peak times. The amount of heat that's stored can be altered using the controls on the storage heater unit.
Basic controls
Basic storage heaters have an input switch and output switch (also called heat boost on some models).
The position of the input switch should be changed to reflect how cold the night and following day is predicted to be. The input switch is normally
thermostatic, controlling the maximum temperature that the bricks are allowed to heat to overnight. The exact setting needed will depend on the desired room temperature, the number of hours in the day that this needs to be maintained, and the room's rate of heat loss under a given set of circumstances. Some experimenting may be needed to find the relationship between forecast outside temperature and best input setting for a particular room. Most storage heater users follow simpler guidelines; for example, in the middle of winter, it's often appropriate to turn the input switch to its maximum setting. There is no need to touch the input switch on a daily basis if you're expecting the same sort of weather for weeks at a time. There is no need to touch the input switch during the day, as storage heaters only use electricity overnight when it's cheaper.
The output switch does require attention throughout the day. Before going to bed, the operator should switch the output to its minimum setting. This keeps as much heat in the bricks as possible. Enough will leak out into the room to make it warm in the morning. Only in exceptionally cold circumstances will the operator require output overnight. The operator may wish to slowly increase the output switch during the day to try and maintain the temperature in the house. Increasing the output will allow the heat to convect out of the heater. If the house is empty during the day because the operator is at work, the output should be left at a minimum all day and then switched up when returning from work in order to let more heat escape into the house.
Thermostatic controls
A thermostatic storage heater will automatically regulate the temperature in a room throughout the day. However, the operator may wish to switch the thermostatic switch to the minimum setting overnight to stop the room being kept at an unnecessarily high temperature overnight. If the room is empty during the day, it's better to keep the thermostat at the mimimum setting and then increase the setting when the room is occupied in the evening. Some thermostatic heaters also make use of on-peak electricity when there isn't enough stored heat to maintain the requested temperature; the user may wish to be aware o
Environmental aspects
In common with other forms of direct
electric heating, storage heaters are not normally considered
environmentally friendly because most electricity is generated remotely using
fossil fuels, with up to two-thirds of energy in the fuel lost at the
power station and in
transmission losses. In
Sweden the use of direct electric heating has been restricted since the 1980s for this reason, and there are plans to phase it out entirely - see
Oil phase-out in Sweden - while
Denmark has banned the installation of electric space heating in new buildings for similar reasons.and they even impose lower peak loads. The highest peak loads come from instantaneous electric heating, such as
instantaneous water heaters, which create heavy loads for short durations, although instantaneous water heaters may use less electricity overall. High-efficiency
ground source heat pumps are able to use up to 66% less electricity than storage heaters in heating by recovering heat from the ground and are, generally, regarded as preferable even though they use electricity throughout the day. These are not to be confused with air conditioning (A/C) heat pumps which are considered, by this time, to be an environmental liability in some, (in particular hotter climate), countries.
Where alternatives to electricity exist, hot-water
central heating systems can use water heated in or close to the building using high-efficiency
condensing boilers,
biofuels,
heat pumps or
district heating. Ideally wet
underfloor heating should be used. This can be relatively easily converted in the future to use developing technologies such as
solar panels, so also providing
future-proofing. In the case of new buildings,
low-energy buildings such as those built to the
Passive House standard can eliminate the need for conventional
space heating systems.
Further Information
Get more info on 'Storage Heater'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://storage_heater.totallyexplained.com">Storage heater Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |