Choosing Microgeneration
Micro-Combined Heat and Power (CHP)
Micro CHP is an innovative new technology, which has been identified as having significant potential towards reducing carbon emissions. There are several competing technologies based on the type of engine or turbine used as the prime mover. Types of micro CHP include; external combustion engines (Stirling and Rankine), internal combustion engines, and fuel cells. One unit would replace a conventional boiler, which have a current replacement rate of approximately 1.3 million units per year.
These boilers work by capturing the steam which comes from the boiler and using it to drive a turbine which then produces electricity. Check the Combined Heat and Power Association website for the latest information
Delta Energy produced a Research
Report in May 2007 which gives their assessment
of the future prospects for this technology.
At around £3,000 they are more expensive than a high-performance boiler,
but will cut energy bills by £120-£150 a year and have a reduced
VAT rate of 5 per cent. These boilers are very new and may be difficult to
get hold of in the near future. As an alternative, go for an energy saving
gas
condensing boiler.
Also see Micropower Council
Small-scale wind turbines
Small-scale building-integrated wind turbines suitable for urban locations are currently being developed and are starting to become be available to install in homes and other buildings.
Scottish companies include Renewable Devices, which manufacture the Swift
Rooftop Wind Energy System which is just 2m in diameter and produces
1.5kWh of energy every time it turns. It has a payback time of eight
years; but look out for the 1.6m diameter model, due out soon at around £1,300.
The Windsave is a little more
grounded, requiring a pole and plinth, but the manufacturers estimate that
it can save 33 per cent of your annual electricity costs. It's £995
plus VAT (5 per cent) and installation costs. The payback time is five years.
Proven Energy produces a range of different sizes of small-scale wind turbines.
Information from Friends of the Earth Scotland
Renewable Energy Centre list of small-scale wind suppliers
British Wind Energy Association list of small-scale wind suppliers
Also see Micropower Council
Solar water heating systems
Solar water heating systems use heat from the sun to work alongside your conventional water heater. The technology is well developed with a large choice of equipment to suit many applications:
The Energy Saving trust gives a list of certified installers;
Also see Micropower Council
And check out Solartwin, a system invented by an Edinburgh-based engineer and chosen by Edinburgh City Council for installation in sheltered housing at Saughton Mains. The pump is powered by a small photovoltaic solar cell thus avoiding the need to connect the panels to mains electricity.
See: Friends of the Earth Scotland
Renewable Energy Centre’s list of contractors and suppliers
Solar photovoltaics
Solar PV (photovoltaic) uses energy from the sun to create electricity to run appliances and lighting. PV requires only daylight - not direct sunlight - to generate electricity.
The Energy Saving Trust guide to PV gives a list of accredited installers and suppliers
Also see the Micropower Council
Renewable Energy Centre’s list of manufacturers and suppliers
Ground-source heat pumps
Although we may not know it heat pumps are very familiar to us - fridges
and air conditioners are two examples. Ground source heat pumps (GSHP) transfer
heat from the ground into a building to provide space heating and, in some
cases, to pre-heat domestic hot water.
See Energy Saving Trust for more information and a list of accredited installers and suppliers.
and Micropower Council for details
Renewable Energy Centre’s list of manufacturers and suppliers
Micro-hydro systems
Hydro-power systems convert potential energy stored in water held at height
to kinetic energy (or the energy used in movement) to turn a turbine to produce
electricity.
For more information and a list of accredited suppliers and installers see Energy Saving Trust
and Micropower Council for details.
Renewable Energy Centre’s list of small-scale hydro-electric suppliers
Biomass Heating
Biomass is organic matter of recent origin. It doesn't include fossil fuels,
which have taken millions of years to evolve. The CO2 released when energy
is generated from biomass is balanced by that absorbed during the fuel's
production. We call this a carbon neutral process.
See Energy Saving Trust and Micropower Council for details.
See also: Friends of the Earth Scotland
Renewable Energy Centre's introduction to Biomass and Biofuel and a list of suppliers
Installers
Here are a few more companies not mentioned so far that offer installation of most types on micro-renewables. A mention here does not necessarily represent an endorsement. Many more can be found at The Renewable Energy Centre.
(1) iso energy
Full range of services including insulation, heat pumps, solar panels, wind turbines and mini-hydro. Based in Surrey.
(2) Solstice Energy
Solstice Energy design, install and commission photovoltaic systems for domestic, commercial and community buildings. Based in London.
Advice and installation of wind, solar, biomass and hydro. Based in Wales.
(4) The National Energy Foundation's Log Pile project
Promoting wood fuel.
(5) Solar Sense
Solar water heating based in Wales.
(6) Solar Century
(7) Bryan J Rendall (Electrical) Ltd (Orkney)
An approved and accredited SCHRI supplier & installer Bryan J. Rendall
(Electrical) Ltd have an extensive portfolio of renewable energy projects
ranging from householder and community energy schemes on off grid Scottish
islands to multi megawatt offshore wind farms with locations stretching from
California to Australia.
(8) Eoltec
Eoltec is an experienced engineers, Wind Energy Systems designer and
manufacturer, focused on the development and production of modern
medium size wind turbines (6 to 300kW).
