The most common fuel used to power central heating in the UK is mains gas, but with over four million households not connected to the mains supply, there is a need for alternative options.
LPG tank gas, oil-fired, and wood-fuelled systems are all available, and there are now fully electric central heating boilers on the market, which can power a standard ‘wet’ central heating system.
In terms of heating the home, electricity is usually associated with storage heaters, but electric ‘flow’ boilers can now heat both the hot water in the radiator circuit, and the hot water for domestic use; taking the place of a gas boiler where gas is not available.
Using electricity to power a central heating system may be best suited to smaller properties and flats, where it will be most cost-effective and where the installation of a storage tank for oil or LPG is not possible.
How do electric boilers work?
Electric boilers can work with standard radiators and pipe work, and can also heat domestic hot water via a coil in the hot water cylinder.
While gas and oil boilers use the heat from the burning process to indirectly heat the water in the central heating circuit, electric boilers heat it directly.
A heating chamber inside the boiler contains a high-powered element; this heats the water as it passes through the chamber and flows on to the radiators.
The boilers are almost silent in operation and are generally quite slim and small in design. They can often be fitted in a cupboard space, and do not require a flue. Without a flue, there are no exhaust gases, and there is very little heat loss from an electric boiler; some manufacturers state that they can be up to 99% efficient.
The use of electric boilers for central heating is restricted to some degree by the amount of power that can be drawn from current domestic electricity supplies. There are 11KW models available which have been designed to match the existing supply, to give the maximum amount of power.
Electric boilers can be used with open vented or sealed central heating systems, and can also be used in conjunction with underfloor heating. With no flue or tank needed, there is much more flexibility when it comes to locating the boiler, and there is no requirement for an annual service, which will save £50 – £100 a year.
Why use electric?
In larger properties it may be necessary to install more than one boiler, and you should question whether electricity is the right choice if your house would need multiple boilers, as the running costs may be prohibitive.
In smaller properties or flats where less demand is placed on the central heating and it is likely to be in less frequent use, an electric boiler could be the best answer.
The heating system can take advantage of the ‘economy seven’ tariff to heat the property early in the day, and if only used moderately throughout the day on the more expensive tariff, could be cost-effective.
In general, however, the price of electricity makes it the most costly form of fuel for a wet central heating system; it is also a high carbon producing fuel, so less environmentally-friendly.
Installation and running costs
The cost of installing a full heating system with radiators, pipe work, and a boiler will vary greatly depending on the size of the house and the type of system.
You could expect to pay around £2,500 – £5,000 for an entire central heating system to be installed. Electric boilers alone are generally cheaper and can range from £300 up to £1000 for the most sophisticated boilers.
The cost of running an electric central heating system is likely to be much more expensive than most other types of central heating systems, simply because of the price of electricity.
A typical three bedroom UK household using 16,000 kWh of heat output per year could be paying in excess of £2,000 using electricity.
As a comparison a gas central heating system would cost roughly £700 – £1,000 for the equivalent amount of heat output.
Finding an installer
The installation of an electric boiler should only be carried out by a qualified electrician. Due to the high power rating, the boilers require their own dedicated supply from the consumer board, and cannot be connected to the ring main.
The wiring of these higher powered cables should only be undertaken by a professional. If you are replacing a gas boiler with an electric boiler, bear in mind that anyone working on the boiler or the gas supply should be gas safe registered.
If a full system is being installed, there may also be a requirement for a plumber to lay the pipe for the central heating circuit.
Electricity is an option for central heating, and highly efficient ‘flow’ boilers have been introduced, which heat the water in the system directly, rather than via a heat exchanger as a normal boiler would.
Gas is the most commonly used fuel for central heating in the UK, as it is one of the cheapest and least harmful to the environment.
For the four million houses where gas is not available, wood fuelled systems, oil-fired systems, and tank gas systems are alternative options; although each requires the storage of the fuel on the property.
In smaller properties and flats, the use of electricity for central heating may be the most viable option. If there is no gas supply and no space to store fuel, an electric boiler can be installed without the need for a storage tank, feed and expansion tanks, or a flue.
Larger properties may require multiple boilers to fully heat the home and meet the demand for hot water; this could prove very expensive in terms of running costs, and may not be viable for bigger homes.
If you are considering using electricity as a fuel to power your home, make sure you think carefully about how much the system will cost to run.