Electric heating often gets a bad name and people often ask why you would choose electric radiators over gas. The answer is lots of people have no choice! According the Department of Environment and Climate Change (DECC) in 2007 nearly half a million postcodes were off the gas grid. You may also be surprised to learn that almost half of GB off-grid households are in urban areas. So if you have no gas connection what are your options?
90% of urban off-grid areas rely on electricity as their main heating fuel. Regulations of flammable and contaminable fuels prevent the use of oil in densely populated areas, alongside the lack of space for storage tanks and difficulties with delivery.Many old mills and commercial properties have been converted into flats and landlords do not want to install gas due to the cost of installation and maintenance regulations. Health and safety regulations also prevent mains gas installation in buildings above 5 storeys high following the collapse of the high rise Roman Point apartments in 1968. So if electric heating is the only option, what solutions are available?
Storage heaters were popular post war to try to even out demand. They encouraged people to use more power overnight by making the off peak rate cheaper. However, most people who have ever lived in a flat with storage heaters complain about the lack of controllability. They emit heat during the day when most people are at work and are often getting cold again by evening. So you are either far too hot or freezing cold. Modern storage heaters claim to have better controllability and programmability but prices start from £500 for a 500w and go up to £800 for a 1500w.
Infrared heaters use radiant heat, which means they heat the person or object next to them. When you stand next to a bonfire you are experiencing radiant heat. They are a good solution in a big open space, such as a warehouse or smoking area, where you want to heat the person directly underneath rather than the whole space.
Modern electric radiators are fully programmable and have individual thermostats on each unit. This means that you can have your heating come on when you want it and it will automatically switch off when up to temperature. Therefore, you will only be using the power that you need, rather than using 7 hours of power overnight, whether you need it or not. It is also worth considering the thermal performance of the radiator you choose. This video demonstrates how slowly the unit cools down once it has been switched off and compares it’s cool down with a competitor. Whilst it is true that all electric radiators are 100% efficient (ie all 1kw radiators will draw 1kw of power if drawing power for an hour), the thermal performance and accuracy of the thermostat will have an impact on how long the unit needs to draw power for.
Rural areas generally have more options. 53% of rural off-grid households use heating oil, as they have more room to store it and delivery is easier. Although the tanks are an eye-sore! Heavy snow in winter 2010/11 saw an increase in demand of 40%. This led to a massive hike in prices. However, oil is relatively cheap at the minute. Communities often group together when purchasing oil to get a better price and if you have got enough room, buy as much as you can in the summer when it’s cheaper.
Wood burning stoves
Wood is renewable and therefore sustainable. It is also carbon neutral as it expels the same amount of carbon dioxide as it has absorbed through its lifetime. It is also possible to power central heating and supply hot water with a wood burning stove.However, on the down side some research* suggests woodburning stoves may increase the risk or severity of asthma, particularly in children. It is also recommended to have your chimney swept regularly, ensure good ventilation and fit carbon monoxide alarms to guard against CO poisoning.
Microgeneration; Direct heat
Microgeneration refers to the small scale generation of power by individuals, businesses and communities. It is possible to generate electricity or heat in your own home for your own use. The following technologies produce heat directly.
Air source heat pumps
Air source heat pumps absorb heat from the air and use it to heat radiators, water and underfloor heating. They may also be used to cool the property in the summer. They are often regarded as an excellent choice because they can turn 1kw of electricity into 3.5kw of usable heat. This is known as the coefficient of performance (CoP) ie/ what it produces vs what it uses. However, the CoP is dependent on the weather. The colder the external temperature, the harder the pump has to work to produce heat. Therefore, in winter the CoP may fall below 2.5.The disadvantages of an air source heat pump is that they can cost around £7500 to install and require enough space for the unit on the outside of the building.
Ground source heat pumps
A ground source heat pump draws heat from the ground. It requires enough room in the garden to dig a hole and bury the pipes. It may cost up to £15,000 to install. The advantage of a ground source heat pump over an air source heat pump is that the temperature in the ground doesn’t fluctuate as much as the air temperature. Manufacturers claim that this results in a more consistent CoP of 4 all year round.
Biomass boilers work in a very similar way to conventional boilers except they are powered by wood chips. They can make use of the millions of tonnes of waste wood that goes into landfill every year. In terms of running costs they appear to be very cheap, with manufacturers claiming as little as 2.9p per KwH. However, you have to have enough room in your property to store a back up supply of wood in case there is a problem with your supplier and ash has to be emptied from the boiler every 4 weeks.
Microgeneration; Indirect heat
The following technologies produce heat indirectly by producing the electricity used to power heating.
Solar (photovoltaic panels)
The cost of PV panels has dropped significantly over the last few years. With the increased availability of battery storage, solar is still a popular choice. Daylight is converted into electricity by the solar panels meaning you can use all your own electricity for free and sell any unused electricity back to the grid. Despite the recent cut in the Feed In tariff, manufacturers claim there is still a 4.6% yield on investment over a 20 year period. With the addition of batteries to your system, you can use even more of the electricity you generate and get even more value from your solar panels.
If you have enough space it may be possible to have a small wind turbine. You can either purchase outright or lease your land to the company. Similar to solar panels, wind turbines can produce electricity for the owner and electricity can be sold back to the grid.
According to the Office of Fair Trading off-grid houses are less energy efficient. 49% of houses have an EPC rating of F or G, whereas only 10% of on-grid properties fall into these categories. This means that no matter what form of heating system the resident chooses they are wasting money on their fuel bills. Households in rental accommodation are at a further disadvantage as they have very little control over the energy performance of the building.In conclusion, to answer the question ‘how to heat your home if you are off-grid?’, consider the following;
- Choose the best heating solution for your type of property
- Ensure you are on the best tariff. You can contact us for help with comparison and switching.
- Evaluate the energy performance of your building and make improvements as a priority. Consider insulation, glazing, and draught elimination.
- Consider your habits, such as leaving doors open when you leave a room and ensure all radiators or heating systems are programmed to drop back to a setback temperature when the room is unoccupied.
For more information about energy efficiency, electric radiators or switching tariffs contact a member of the team on 01484 213151
* References Belanger K and Triche EW (2008) Indoor Combustion and Asthma. Immunol Allergy Clin North Am; 28 (3): 507 – vii