Solar - Frequently Asked Questions

1. What is solar photovoltaic (PV)?

Photovoltaic means electricity from light.
A solar PV system uses the natural energy from daylight in the form of solar radiation to generate electricity. This is different technology to solar thermal systems used for heating and hot water.

2. Why should I install a PV system?

By installing a solar PV system you will be generating your own clean green electricity from the free energy of the sun. This will not only reduce your electricity bills but since energy use associated with buildings accounts for around 50% of the UK CO2 emissions, installing a PV system will also help reduce greenhouse gases.

3. What is a PV system made of?

Solar PV systems are most commonly made from silicon, the second most abundant element in the planet crust, usually in crystalline form. The modules (sometimes referred to as a “panel”) are made from PV cells usually behind glass that are linked together in series like batteries in a torch to generate power output in the form of direct current (DC). A number PV modules can be connected together to give the desired electrical output.

4. How does it work?

A charge is placed across the cell and as the energy from the sun hits the silicon, an electron is released from the atom. Due to the charge across the cell, this electron then flows towards the positive layer. Once you have an electron flow, a current is generated. This direct current is converted by an inverter in the system to an alternating current (AC) at the same level as the national grid.

Click on the image for more details

5. Will it still work on a cloudy day?

As the electricity generation is dependant on light intensity and not direct sunlight it will work in cloudy conditions but the greater the intensity of the light the greater the flow of electricity. Hence you generate more on sunnier days but the system will still produce electricity on cloudy days.

6. How much will it cost?

There is initial capital outlay to install your system which can be subsidised by a grant under the low carbon buildings programme. Once installed, since daylight is free, the system generates free electricity that requires very little maintenance with no moving parts.

7. How long will it last?

We have been producing solar PV since 1959, early installations of which have been in place for more than 40 years and are still working within their performance specification.

8. How much electricity will it generate?

Each kilowatt peak of PV installed in the UK on average would produce around 800kWh per annum. This varies with geographical location and your accredited installer will be able to estimate your system output depending on the solar radiation levels in your area.

9. Will it produce greenhouse gases?

PV systems generate electricity without producing emissions of greenhouse or any other gases. Based on the current electricity mix, every kWh of electricity delivered to your premises from the national grid will have produced 0.43 grammes of CO₂. At 800kWh per kWp this will save approximately 344g of CO₂ emissions every year.

Over the warranty period this is over 8 tonnes of CO₂ saved.

10. How much space do I need?

Sharp 180W modules are approximately 1m x 1.3m. Therefore a 1kWp system will require around 6 Sharp modules or a space of approximately 8m².

11. Where can I install a PV system?

A PV system should not be installed in shade such as from other buildings or large trees since this will decrease the output from the system. However, although generally installed on a roof, they can be installed on any surface such as facades, sunshades, garages or ground mounted. They are normally installed in locations that receive sunshine through most of the day i.e. from East through South to West. However, maximum output will be facing due south and between 30-40 degrees from horizontal.

12. Do I need planning permission?

Some authorities require planning permission especially for listed buildings or within a conservation area. Although planning permission for solar PV is not generally required, Sharp recommends that customers should always check with their local authority before having a system installed.

13. How much will a system cost?

There are a number of factors that contribute to the cost of a system including the size of the system, module type, component parts, whether new build or retrofit, accessibility such as scaffolding requirements and labour costs. Sharp recommend you speak to your local accredited installer for a full quote. However, under the Low Carbon Building Programme, grants are available against your total turnkey solution cost – visit www.lowcarbonbuildings.org.uk for more information.

14. How do I get a PV system from Sharp?

Sharp has a network of accredited installers and distributors. For details on our accredited installers please either e-mail solar@sharp-uk.co.uk, visit our website or call 020 8734 2133.

15. Where can I get further information?

Visit our website at www.sharp.co.uk/solar or telephone 020 8734 2133.