Frequently Asked Questions
How do solar panels work?
Solar Photovoltaic (PV) panels can be attached to roofs, walls or frames and are made up of photovoltaic cells. Each cell is made from one or two layers of semiconducting material, usually silicon. When light shines on the cell it creates an electric field across the layers. The stronger the sunshine, the more electricity is produced.
PV cells come in a variety of shapes and colours, from grey "solar tiles" that resemble slate roof tiles, to panels and transparent cells that you can use on conservatories and glass.
The strength of a PV cell is measured in kilowatt peak (kWp). That is the amount of energy the cell generates in full sunlight.
What happens on a cloudy day?
Solar PV panels use light to generate electricity, so the modules still work when it is cloudy, although when it is overcast they are less efficient. When it is slightly overcast, the panels may produce around half the power they would in sunny conditions. When the sky is heavily overcast, this could reduce further. Temperature is less important than the amount of light. In fact, clear cold days provide perfect conditions because PV modules operate better at cooler temperatures.
Do Solar PV panels work when covered in snow?
It depends how much snow. If you imagine standing in under a glass roof covered in snow, light still get through. Reduction in efficiency is similar to cloudy conditions (see above.)
Will I still need to pay for electricity?
Yes, you will still receive an electricity bill from your energy supplier (e.g. British Gas, Eon, Scottish Power, etc.) because a typical PV installation on your home or building will not provide you with 100% of your electricity requirements. However, you should find that you will be paying much less than before you had a solar PV system installed because you are generating your own free electricity during daylight hours.
What is FIT (Feed-in Tariff)?
In 2010 the Government introduced the Feed-in-Tariff (FiT) in a bid to increase the market for renewable clean energy by offering an incentive for households, businesses, local authorities, farmers and landlords to start generating their own energy, which would allow them to protect themselves against future price rises in fossil fuels, cut carbon emissions and receive payment for the low-carbon energy they produce. The FiT incentive ends next year, so 31st March 2019 is the last date that a new installation can submit an application.
You can earn a fixed income for every kilowatt hour of electricity you generate, whether you use it or not. And you can also earn an additional fixed income for every kilowatt hour of electricity you generate and sell back to the grid. The income is guaranteed for 20 years and is index-linked.
If you want to make the most of solar technology - and save even more on your electricity bills - try to become as energy efficient as you can; for example, run electrical appliances like your washing machine and dishwasher during the day while your panels are producing electricity.
By investing in solar energy now, the income you will generate is guaranteed for the next 20 years. Ofgem will administer the FIT scheme and energy suppliers will be responsible for payments to their customers.
How do I apply for the Feed-in tariff?
You can apply to your electricity supplier for the FIT once your installation has been commissioned and certified by the Microgeneration Certification Scheme (MCS). To qualify for the FIT, it is a condition that the installation must be carried out by a MCS approved installer using MCS approved PV panels.
Who pays me for the Feed-in tariff?
Energy suppliers pay the FIT to customers who generate the clean electricity. When you apply for the FIT, you should ask your energy supplier how and when payments will be made. Payments must be made at least quarterly. Ofgem will regulate and oversee the scheme.
Where does the money come from?
The money to pay the producers of green energy comes from a small levy on every UK energy consumer.
How long do the feed-in tariffs last?
For solar PV, the tariff lasts for 20 years. The tariffs are index-linked and guaranteed by the government.
Can future governments renege on this agreement?
The law governing the Feed-in tariff constitutes ‘Primary Legislation’, and any future government would be in breach of contract if it reneged on the guarantee to honour the tariff. Therefore, payments to individuals will not change over this time - in fact, being index-linked, they will increase with inflation.
Are any other requirements necessary?
A residential property must have an Energy Performance Certificate (EPC) of level D or above. This does not apply to schools or community buildings. An EPC is a standard document showing how efficiently a property uses energy and contains the brightly coloured graphs you may have seen on estate agents' websites. An EPC is produce by a qualified assessor, known as a Domestic Energy Assessor (DEA).
Will I still have power if there is a power cut?
Unfortunately not; if there is a power cut your system will automatically switch off. This is a safety measure designed to stop electricity leaking onto the National Grid and protects people who may be working to restore the power.
How much does Solar PV help my carbon footprint?
Each kWh of electricity produced by your system will prevent 568grams of CO2 from being released into our atmosphere. This is because it displaces grid electricity produced from power stations which is rated by the government to produce 568g CO2 per KWh.
Can I install the system myself?
Yes, you can install the system yourself but you must remember that you will not be entitled to the feed-in-tariff unless your system has been installed by an accredited MCS installer.
Do I need planning permission?
Generally, planning permission is not required for solar panels on rooftops, although installers do need to adhere to certain rules. Even in conservation areas solar panels on rooftops do not necessarily require planning consent. Exceptions may apply if your property has Listed Building status or is subject to an Article 4 direction. It's best to check with your local council planning officer if you are not sure. Even where standard panels would not be allowed, there are panels designed to look like slates which have been used on Heritage properties.
Ground mounted systems over 9m2 will need planning permission.
Further information may be obtained from the Government's online planning and building regulations site at www.planningportal.gov.uk.
What is the VAT rate on Solar PV?
Renewable energy installation is subject to a VAT rate of 5%.
What does “MCS approved” mean?
MCS refers to Microgeneration Certification Scheme which is focussed on ensuring the quality of renewable technology installations and products. It has been developed over the last three years and is an industry led and funded scheme. MCS certification acts as a mark of competency. It is globally recognised, demonstrating that a company is committed to meeting rigorous and tested standards. This means customers are safe in the knowledge that they are dealing with an installer who works to the highest quality at all times. To be certified as “MCS approved”, an installer must undergo rigorous testing and inspection on every aspect of installing and maintaining microgeneration technology.
Is there any protection for consumers?
All MCS registered installers are required to hold membership of the Renewable Energy Consumer Code (RECC). This is a Consumer Code backed by the Office of Fair Trading and is designed to ensure high standards of service before, during and after a contract. There are strict rules against pressure selling, giving misleading information and how deposits or advance payments are charged and use. You can download a copy of the Code at www.recc.org.uk/consumers.
Installers are also required to take out a Workmanship Warranty Insurance policy which is backed by RECC and protects consumers in the event of the installer going out of business.