Solar Photovoltaic (PV) for Homes FAQ's

Solar PV is one of the fastest growing renewable technologies in the UK and is suitable for almost any property. FIT payments can provide a source of income and installing solar will enable you to save on your utility bills and reduce carbon emissions. They are well suited to the UK climate and work even on cloudy days. However, there are some factors to consider when deciding whether solar PV is right for your property such as; which way your roof is facing, shading around the solar installation area and how much roof or land space you have available.

We offer solar panel mounting systems that allow us to mount a system in a place that suits your site and requirements – whether that is on top of your existing roof tiles (on roof), flush with your roof tiles (in-roof) or on a flat roof or the ground.

Energy Performance Certificate’s give information on how energy efficient your home is and suggests how to make your home more energy efficient to reduce your energy costs. From April 1st 2012, it is compulsory for homes with a solar installation to have an EPC rating of Band D or above in order to receive the full Feed-In Tariff payments. We can send a trained surveyor to inspect your home and provide you with an EPC if you haven’t recently had an EPC carried out at your property.

Once we have visited your site and carried out a site assessment and survey, we will be able to design a system for you and work out how much your system will generate. We do this using a Standard Assessment Procedure (SAP) calculation for solar PV, the method recommended by the government.

Solar PV works from daylight and not direct sunlight, but normally more power is produced on a sunny day than on an overcast or cloudy one. PV panels do not produce energy in the dark and so during the night electricity is drawn from the grid in the normal way.

The payback period of a system will depend on the size of the system and ease of installation and may vary from system to system. However, we would expect an average 4kWp system to take roughly 5 to 8 years to pay for itself, after which time any money earnt will be profit for the owner.

Most roofs are strong enough to support a PV installation without any reinforcement, but we will perform a site survey and make an assessment of this prior to installation.

For systems less than 4kWp we will inform them once the installation is complete. For larger systems, permission will need to be gained in advance from the network operator. Responsibility for gaining permission can be discussed at the site survey prior to installation.

This varies depending on the size of the installation, however, an average 4kWp installation takes 1-3 days.

To yield high results from a Solar PV system your roof or land installation area will need to be facing towards the sun when the suns radiation in relatively strong. To yield the highest results the roof will need to be facing South, however East and West facing orientations have still shown strong results. A site survey will determine the best option for your property.

Any shade from trees, neighbouring buildings or overhead cables can have a huge impact on the performance of your PV system, so panels should be sited to avoid shading as much as possible. A site survey will determine the best install location for your property or land.

To fit a solar PV system we will need a minimum area of 10m² of clear roof space to make your investment payback effective.

The prices of oil and other non-renewable sources of energy are on the increase. This trend will continue into the future, getting more dramatic as shortages of supply increase. The price of your electricity from solar will never increase as the fuel is free and infinite!

A 4kWp system can generate around 3,800 kilowatt hours of electricity a year in the south of England – roughly equivalent to a typical household's electricity needs. It will save nearly two tonnes of carbon dioxide every year.

Since April 2012 planning permission is no longer required for domestic solar roof-mounted PV installations. Some exceptions however are listed buildings and properties in a National Park, Area of Outstanding Natural Beauty or a conservation area. In all cases you should contact your local authority to seek clarification.

Watts are the units used to measure energy use or production and a kilowatt is a 1000 watts. kWp stands for kilowatt peak, which is the power that a solar panel will produce if it has ideal conditions. kWh stands for kilowatt hour, which is how many kW (kilowatts) are produced in one hour.

This varies depending on manufacturer but most panels have an expected life well in excess of 25 years.

Usually dust and dirt washes off when it rains if the panels are installed at an angle of at least 15 degrees. In extreme cases, dirt may cause a power reduction of about 10%.

Solar panels generally require little maintenance since there are no moving parts, however it is recommend to maintain your solar equipment to ensure the ongoing efficiency of the system. The frequency and type of maintenance required will depend on the type of system you have installed and it’s location. We can offer annual or bi-annual inspections and servicing of your system. Please view our solar maintenance page for further information.

Clear Sky Energy’s knowledgeable and professional installers will provide you with a full explanation of your system once it is installed and also talk you through its operation and settings. In addition you will get a clear and comprehensive Operation Manual for your specific system, and you will be able to get in touch with us at any time to ask questions or raise issues.