South Yorkshire Energy Efficiency Advice Centre

South Yorkshire Energy Efficiency Advice Centre is promoting a greener future to all our customers.  There are many effective alternatives to fossil fuels to meet your energy requirements and reduce carbon dioxide emissions.  Renewable energy is defined as a source that does not run out, such as solar, wind, biomass or water power.  However, alternative sources are available that are continually replaceable such as, waste products or crops.

Customers can change their existing electricity supply over to a green tariff, where the electricity is generated from a renewable source.  Contact you supplier for more information on what green tariffs they offer.   

A number of new technologies that produce heat or electricity can be installed in or on your home.  Not all technologies are suited to every home so research is needed to establish which is the most appropriate technology to suit your home.  The Energy Efficiency Advice Centre can offer free impartial advice on the best renewable technology for your home and what grants are available.

For a brief overview of the main types of renewable technologies available please read on, alternatively, for more detailed and technical information contact the advice centre. 

The UK benefits from some of the highest average wind speeds in Europe, making it an ideal candidate for wind energy.  Generation of wind energy involves the conversion of energy contained within wind to rotate aerodynamic blades producing mechanical power, which is then converted into electrical power.  Wind turbines are available in a range of sizes and output dependant on the households needs.

There are two main types of wind turbines:

• Mast mounted - which are free standing and located near the building(s) that will be using the electricity.

• Roof mounted - which can be installed on house roofs and other buildings.

The cost of a professionally installed wind turbine system can vary significantly so it is important to do as much research as possible.  It is recommended to obtain at least three quotes from accredited installers.  You can get a list of local accredited installers via the Low Carbon Buildings Website.  A typical 2.5kW system costs approximately £11,000 - £12,500 including installation.  A typical 6kW system costs approximately £18,000 - £25,000.  Although, some of the smaller systems can cost just £1,500 for a 1kW system.

There are significant issues that need to be considered before proceeding with a wind turbine installation:

• Wind speed increases with height so it is ideal to have a turbine installed on a mast or tower.

• Generally the best site would be a hill top with clear exposure, free from obstructions such as large trees, houses or other buildings.

• Suitable for remote off grid locations where conventional methods of supply are expensive or impractical.

• Suitable where wind speed is 4 - 5 m/s or more. 

• Planning permission may be required when installing a wind turbine.  You will need to contact your local planning office for more information.

The government funded Low Carbon Buildings Programme provides grants to help with the costs of installing small-scale wind technologies.  To be eligible for a grant you will need to use a certified installer and products. 

Hydro power systems harness the kinetic energy of falling water to produce electricity.  Hydro electricity is a very successful method of generating electricity and is one of the main sources of renewable energy in the UK as useful power may be produced from even a small stream. 

The following points needs to be considered before a hydro power system is installed:

• Hydro power requires the source of water to be relatively close to where the power will be used or to a suitable grid connection.

• Hydro systems can be connected to the main electricity grid or as a part of a stand alone (off grid) power system.

• Hydro costs are very site specific and are related to energy output.

• Energy available in a body of water depends on the speed of the water flow rate and the height that the body of water falls from.  The bigger the height the more energy will be generated.

For houses with no mains connection but with access to a micro hydro site, a good hydro system can generate a steady, more reliable electricity supply than other renewable technologies at a lower cost. Total system costs can be high but often less than the cost of a grid connection and with no electricity bills to follow.

Prices of a hydro power system depend on the site and energy output: For low head systems (assuming there is an existing pond or weir), costs may be in the region of £4,000 per kW installed up to about 10kW and would drop per kW for larger schemes.   For medium heads, there is a fixed cost of about £10,000 and then about £2,500 per kW up to around 10kW - so a typical 5kW domestic scheme might cost £20-£25,000. Unit costs drop for larger schemes. Maintenance costs vary but small scale hydro systems are very reliable.

The government funded Low Carbon Buildings Programme provides grants to help with the costs of installing small scale hydro technologies.  To be eligible for a grant you will need to use a certified installer and products.

Heat pumps are a well established technology that can offer a significant CO₂ saving where gas central heating is unfeasible.  Heat pumps extract available heat energy from a source and release it in another location at a higher temperature.  There are three types of heat pumps currently available: ground source, air source and water source.  Heat pumps have some impact on the environment as they need electricity to operate the pump, although the heat they extract is constantly being replaced making it renewable.

Ground

Ground source heat pumps use a buried ground loop that transfers heat from the ground into a building to provide space heating and in some circumstances can be used to pre-heat domestic hot water.  The system comprises of a length of pipe buried in the ground (either in a borehole or a horizontal trench), a heat pump and a heat distribution system.  The heat pump uses minimal amount of electricity to pump the system and works in the same way a refrigerator does by extracting heat from the ground and using it in your home.  The distribution system can work well with underfloor heating or radiator systems.  Underfloor heating is better as it works at a lower temperature and provides a more efficient output. 

Air

Air source heat pumps work in the same way using air.  However, they don’t need a collector system as they extract the heat from the source at the point of use. 

Air source heat pumps can be fitted outside a house or in the roof space.  Air source heat pumps perform better where air temperatures are warmer.

Water 

Water source heat pumps work in the same way using water and like air systems don’t need a collector system as they extract the heat from the source at the point of use. 

Water source heat pumps can be an effective way of providing heating in homes that are near a river, stream and lake where alternative fuels such as gas are unavailable.

Costs

An average system can cost from £6,500 - £11,500.  However, this would not include the price of the distribution system.  Prices of systems vary with property and location so it is recommended to obtain at least three quotes.  Based on current fuel prices and technology costs the energy saving made by using a heat pump can pay back the initial investment cost in 8 - 15 years.  The payback will depend on type of system and whether or not the system was part funded by a grant.  

The government funded low carbon buildings programme provides grants to help with the costs of installing a ground source heat pump and will soon provide a grant towards air source heat pumps.   

Solar Photovoltaic (PV) can be used to supply electricity to a household.  Solar PV systems convert light into electrical power using a thin layer of semi-conducting material, usually silicon, encased between sheets of glass or plastic.  PV systems come in a range of sizes ranging from large panels mounted on the roof to small roof tile effect panels.  Typical systems can last for up to 50 years with little maintenance requirements.

PV systems are not suitable for all property types as there are many factors to consider:

• The roof should be free from all forms of shading 

• South facing roofs with an incline of 30-40^o will be most efficient 

• Planning permission will only be required if the property is listed, in a conservation area or in an area of outstanding natural beauty

PV systems are now widely available but the cost can put many people off installing a system.

Cost
For an average system costs can range from £5,000 - £9,000 per kW installed with most domestic systems usually between 2 and 2.5 kW.  Solar tiles and roof-integrated panels can cost more than conventional panels.  A PV system can provide a household with savings of up to £125 per year on their electricity bill.

The government funded low carbon buildings programme provides grants to help with the costs of installing solar PV technologies. To be eligible for a grant you will need to use a certified installer and products.

Solar thermal systems use solar energy to produce domestic hot water.  The solar panel needs to be placed in a good south facing position as with a PV system.  Fluid is pumped through the solar panel and is directly heated by the sun.  The fluid then heats the water via a heat exchanger within a hot water tank.  There are two main types of solar collector:

• Flat plate collectors - a glazed, flat, dark-surfaced absorber plate which contains metal tubing.  The plate absorbs incoming solar energy and heats up the fluid circulated through the tubing.  

• Evacuated tube collectors - Parallel rows of transparent glass tubes contain an absorber insulated by a partial vacuum.  These are more effective throughout the year than flat plates but tend to be more expensive. 

An efficient solar hot water system can provide a household with up 70% of all hot water needs and during summer months provide 100%.  An additional hot water system is required to provide for any deficit. 

Cost
The cost of a professionally installed system can vary significantly.  Typical installation costs are around:

• £2,000 - £4,000 for a flat plate collector system

• £3,000 - £4,500 for an evacuated tube system

The average domestic system reduces CO₂ by around 350 - 400kg per year, depending on the fuel replaced. This could save you around £50 a year.

Biomass is plant material or animal waste that is used as a fuel source.  For small-scale domestic applications of biomass the fuel usually takes the form of wood pellets, wood chips or wood logs.   Using biomass as a source of fuel has both environmental and financial advantages.  The burning of biomass is what is known as a carbon neutral process – the CO₂ released when energy is generated from biomass is balanced by that absorbed during the fuels production.  Using a local fuel source is more economical as well as reducing the environmental impact of transport.

When thinking of installing a biomass system the following issues need considering:

• Storage space for fuel and appropriate access to the boiler for loading 

• Local fuel supplier

• Flue – the ventilation system must be specifically designed for wood fuel appliances.

• Regulations – the installation must comply with the Building Regulations.

• Wood can only be burnt in exempted appliances under the Clean Air Act

• Planning issues may need to be considered if the building is listed or in an area of outstanding natural beauty.  It is advisable to contact your local planning office before any work commences.

Cost
Individual room heaters generally cost around £3,000 installed.  Savings will depend on how much they are used and which fuel you are replacing.

The cost for boilers varies depending on the system choice; a typical 15kW (average size required for a three-bedroom semi detached house) pellet boiler would cost around £5,000 - £11,000 installed, including the cost of the flue and commissioning.  A manual log feed system of the same size would be cheaper.

A biomass powered boiler could save you up to £350 per year on your utility bills and an average CO₂ saving of 6 - 7 tonnes per year.

The government funded low carbon buildings programme provides grants to help with the costs of installing biomass technologies.  To be eligible for a grant you will need to use a certified installer and products.