Even on cloudy days there is sufficient free clean energy available from the sun. We can make use of this in a number of ways. Passive solar is where a building is designed to make use of the sun, the simplest way is to have large windows and other glass areas southerly facing with small windows to the north. Collecting the suns energy and transferring it into a useful source is another way. Different parts of the country have different levels of sunshine, in Cheshire this is around 1,100 to 1,200 kWh/m2 a year, sufficient to expect a solar collector to provide a typical household with at least half its hot water. There are many opportunities to install solar heating and other systems in Cheshire, particularly when refurbishing a property or for the many new build homes in the area. As with most technologies it is cheaper to install solar systems at the building stage.

There are different types of systems under two different technologies:

• solar water heating collectors which provide hot water
• photovoltaic collectors which convert the suns energy into electricity.

Solar Water Heating

A number of solar hot water schemes have been implemented in Cheshire. Hot water schemes have been installed by Solar Twin www.solartwin.com (based in Chester) at Kingsmead School, Wistaston Green School and Beeston Outdoor Education Centre. At Kingsmead School a scheme providing around 30% of the hot water needs has been implemented.

The hot water demand for the school is provided partly by a solar thermal hot water scheme.

Cost: £15,500
Supplier: Solar Twin
System: 4 portait panels mounted on bespoke A frame heating a 750 litre low pressure heat store preheating water prior to biomass heating.
Max System Hot Waste Storage: 750 Litres:
Total Potential Hot Water Requirement: 2,000 kwh/yr
Total Predicted Water Demand: 10,000 kwh/yr
AS Proportion: 20-30%



Collectors come in several types the most common are flat plate and evacuated tube designs. These are generally placed on a roof, the more south facing the roof the more light it receives, direct north facing roofs are not cost effective. The pitch of a roof is also important, between 30 to 60 degrees are best. If the roof isn't pitched panels can be mounted on a frame at an optimum angle. You will need around 2.75m2 of collector to heat water for two people, or 4.12m2 for up to four people.

Halton Borough Council case study.

Photovoltaics (PV)

Kingsmead School, Northwich has a 5kwp pv scheme installed that will provide around 15% of the school energy deman. This scheme cost £28,000 to implement with 50% met by the DTI Major Photovoltaic Demonstration Programme.

Scheme Details:

Panel Type: Sanyo Hybird Crystalline and Amorphous Module
Max System Size: 5 kwp
Energy Yield: 4,500 kwh/yr
Appox Total Energy Demand: 20,000 kwh/yr
Potential Contribution: 3,000 kwh/yr
AS Proportion: 15%
Scheme Provider: Solar Century

Beeston Outdoor Education Centre, near Tarporley has installed a 1kwp scheme that will provide electricity for the IT equipment at the centre. This scheme cost £7,500 to implement with 50% met by the DTI Major Photovoltaic Demonstration Programme.

Scheme details:

Sanyo Hybrid Crystalline and Amorphous Module
Max System Size: 1kwp
Energy Yield: 950 kwh/yr
CO2 saving: 409 kg year
Scheme Provider: Solar Century

Beeston has also installed a Power Education Energy Kit including pv and small scale wind and is used by visiting schools to demonstrate data logging of renewable energy technologies.


Above: Kingsmead School Photovoltaic Array


Each PV cell contains two or more thin layers of semi-conducting material, like silicon. When exposed to light, electrical charges are generated which are conducted away as direct current
When PV systems are connected to the electricity network you can sell electricity generated during the day to an electricity supply company, in the evening this is then reversed and you buy power from the network.

Other applications of PV
PV's are now commonplace. They have many uses such as charging the battery for domestic burglar alarms, lighting in caravans and TV's, calculators, and radios. In the garden you can have solar water heating, and solar fountains, saving on exterior wiring. In some areas of the country parking meters have been installed with solar panels.

For more information look at the following links

www.solarcentury.co.uk/overview/ a pv solutions business
www.est.co.uk/solar/ For solar power grants
www.greenenergy.org.uk For DIY hot water systems, it is useful to contact a solar club. These clubs are not for profit initiatives designed to make solar water heating cheaper and easier to install
www.solartwin.com For installations and DIY
www.solheat.co.uk Solheat for Installations