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Environment and greener living
Other low carbon energy technologies
Along with solar, wind and water, there are three other low carbon technologies you can use to generate energy in your home. These are ground source heat pumps, bio-energy and micro-combined heat and power (micro-CHP).
Grants for low carbon energy
You may be able to claim a grant for some of the costs of installing low carbon energy technologies (also known as renewable energy systems). The links below show what is available.
Ground source heat pumps
What they are
Ground source heat pumps (GSHPs) provide heating and, in some cases, pre-heat hot water. A large pipe full of water and anti-freeze, called a ground loop, captures heat from the ground. This heat is transferred to underfloor heating, radiators or hot water.
What you need to consider
The Energy Saving Trust recommends you think about the following:
- GSHPs can be used with radiators but underfloor heating is better
- you need space and suitable ground for a hole to accommodate a ground loop
- you may need a back-up heating system
For more recommendations from the Energy Saving Trust, click on the link below.
What they cost
It costs £6,000 to £12,000 to install a six to eight kilowatt (kW) system, suitable for a detached house. This varies with property and location.
According to the Energy Saving Trust, running costs are around £540 per year for heating and 50 per cent of your hot water. This depends on factors like the size of your home and how well insulated it is.
Bio-energy
What it is
Bio-energy uses biomass (organic matter) to generate energy; wood-burning stoves are an example of this. Biomass absorbs carbon dioxide (CO2) as it grows, which balances out the CO2 it releases when burned. This is known as a carbon neutral process.
The two main categories of biomass are:
- woody biomass like untreated wood
- non-woody biomass like animal waste, biodegradable products from food processing, and high energy crops (like sugar cane)
In homes, people usually use wood pellets, wood chips and wood logs.
How it works
The main ways to heat a home using biomass are stand-alone stoves and boilers.
Stand-alone stoves heat a single room using logs or pellets. Generally they are six to 12kW in output and some models can be fitted with a back boiler to heat water.
Boilers connect to central heating and hot water systems. They are suitable for pellets, logs or chips and are usually larger than 15kW.
What you need to consider
An accredited installer can provide you with detailed advice. The Energy Saving Trust recommends considering the following:
- you need space to store fuel, good access to load the boiler and a fuel supplier
- the installation must comply with the Building Regulations (Part J)
- if you live in a smoke control area, you can only burn certain fuels and use certain ‘exempt’ appliances – see the link below for more details
- if the building is listed or in an area of outstanding natural beauty, you'll need to check with your local authority planning department before fitting a flue
What it costs
Stand-alone room stoves cost £2,000 to £4,000 including installation.
The cost of boilers depends on the fuel they use. A typical 20kW pellet boiler – which would heat a three-bedroom semi-detached house all year – costs £5,000 to £14,000 including installation. A manual log feed system of the same size would be slightly cheaper.
Unlike other forms of renewable energy, you’ll need to pay for fuel. The costs depend on:
- the kind of biomass you buy
- whether you buy in bulk
- the distance from your supplier (the further away you are, the higher the transport costs will be)
If you live in a rural area, near to sources of cheaper biomass like waste wood, running costs will be cheaper.
Micro-combined heat and power (micro-CHP)
What it is
Micro-CHP is a new technology that produces electricity and heat for your home. A micro-CHP unit resembles a gas-fired boiler and produces electricity from fossil or renewable fuels.
Whenever electricity is created, heat is produced as a by-product. Normally this heat is wasted but, with micro-CHP, it’s used for heating and hot water.
Is your house suitable?
Current micro-CHP systems are best suited to:
- larger homes with three or more bedrooms
- older homes where it's hard to improve insulation, like houses with solid brick walls
What it costs
To get the most from micro-CHP, you’ll need to install heat networks (usually using piped water). These carry high costs: £500 to £800 to install each kW of generating capacity you need. Typically the payback time on your investment is more than five years. However, micro-CHP uses less fuel, so your energy costs will be significantly lower.
This technology is still in development and it’s not an all-purpose solution, so you’ll need to check its suitability carefully.
