Generating your own heat and power is the ultimate in eco-living – and with technology improving and energy prices rocketing, this could be the perfect time to invest for the future.
Solar hot water heating
Solar thermal panels can provide around 70% of your hot water for free. Water flows through tubes (arranged in panels) mounted on a south-facing roof. The sun warms the water in the pipes to around 60ºC and it is then stored in a hot water cylinder ready for use.
Cost: £3,000 to £4,000, but Government grants can help.
CO2 saving: 350kg/year.
Potential cost saving: up to £300.00 a year, depending on fuel replaced.
Solar photovoltaic (PV) panels
PV panels convert sunlight into clean electricity and a 2.5kWp system (the peak output of the solar system) will provide around half a household's electricity needs. It only needs daylight, so can still generate power on a cloudy day. Depending on the system, if you generate more power than you use, you could be sending the electricity company a bill!
Cost: from £5,000 per kWp, but Government grants can help with outlay.
CO2 saving: 645kg to 1.2 tonnes a year.
Potential cost saving: £250.00 a year.
Wind turbine
Although the technology is improving, roof-mounted turbines are not big enough to generate significant amounts of power, and urban wind speed simply isn't consistent enough – but they are useful for boats and sheds that need just a small amount of power. You will also require planning permission, which may be difficult to obtain. To make real savings, you'll need a 2.5kW to 6kW mast-mounted turbine. If you've got the space and sufficient wind speed, this can generate enough electricity to power the whole house – and any you don't use, you can sell back to the National Grid.
Cost: £11,000 to £19,000 installed, but Government grants are available.
CO2 saving: 1 to 5 tonnes per year, depending on size and location.
Potential cost saving: With enough wind, you may never have to pay another electricity bill.
Ground source heat pump
Pipes buried underground have liquids pumped along them at pressure. An electric heat pump converts the constant temperature (around 11ºC) of the earth to 55 ºC – perfect for use with underfloor heating. It’s disruptive to install but, if you have the space, it can be much more efficient than a traditional boiler.
Cost: 8 to 12kW systems cost £6,000 to £12,000. Grants are available.
CO2 saving: 1.2 to 7 tonnes.
Potential cost saving: £400.00 to £1,000.00 a year.
Air source heat pump
Air source heat pumps extract the warmth in the air and convert it ready to be used in the home – either as warm air pumped through vents or in underfloor heating. They are best suited to off-grid properties and are much easier to install than the ground source option.
Cost: a 6kW system will cost £7,000 to £10,000.
CO2 saving: around 1 to 5 tonnes.
Potential cost saving: £300.00 to £800.00 a year.
Underfloor heating
A hot water underfloor heating system is more efficient to run than radiators, provides invisible warmth and frees up wall space. If you’re renovating a room, this could be the perfect heating solution for a greener home.
Unlike traditional radiators that just heat the air, pipes under the floor concentrate the warmth where you sit or stand, leaving your feet toasty and your head slightly cooler – ideal conditions for genuine comfort.
Radiators also require significantly higher temperatures to heat
a room, while underfloor heating needs around 45ºC to work. This means the boiler needs to work less, reducing running costs and cutting CO2 emissions. It also makes the system ideal for use with renewable technology such as ground or air source heat pumps.
Installation can be disruptive, but next time you’re renovating a room, consider underfloor heating.
It works under almost all floor surfaces and, because it takes up no wall space, your furniture can be positioned anywhere you want.
The next big thing?
Micro CHP (combined heat and power). Micro CHP appliances replace a standard gas or liquefied petroleum gas (lpg) boiler and generate both electricity and heat – it’s rather like having a mini power station in your own home. Generating electricity at a creaky old power station is less than 50% efficient, but electricity generated through a micro CHP boiler is 80% to 90% efficient, saving money and fossil fuels. It’s even possible to feed power back into the National Grid and get paid for it. CHP has been used successfully in schools and hospitals and new domestic units are currently being brought to market.
Cost: from £3,000.
CO2 saving: 500kg.
Potential cost saving: £150.00 to £400.00 per year.
