Home > Learn about solar > Solar panels faq

Solar Frequently Asked Questions

What is a solar panel system?

A method of generating green electricity on your roof, stimulated by strong financial incentives from the government. A solar panel system is a combination of multiple solar panels that generate electricity, the inverter that transforms it into alternating current and the installation materials (e.g. mounting materials and cables). The system needs to be installed by an MCS accredited installer.

What are benefits of solar panels on my roof?

Solar panels are financially attractive for homeowners that have the right roof, they give 100% green electricity generated for your own use, a reduced carbon footprint for your family, can create a drive to improve the energy efficiency of your house, and are considered an investment that increases the value of your house. They have a long lifetime and require very little maintenance.

How attractive is my roof for solar energy?

This depends on the location (Cornwall / Devon are optimal), the roof orientation (South is optimal), the roof angle (35-40 degrees is optimal), the roof shading (none is optimal) and the roof size (at least 8 square meter required). See the solar education for details of each factor.

How much electricity will my system generate?

Outputs in kWh are a combination of solar irradiation (sun received on your location), solar potential (your roofs orientation, angle and shading), system size (dependent on roof size available) and the derate factor (losses of electricity in the components of panels, inverter and cables). On average, a 1kWp would generate about 800 kWh per year (20% of the electricity use of an average 2 bedroom house)

What will the solar system cost?

System costs are the combination of panels (50%), the inverter (10%) and the installation (40%) which includes both labor costs (it takes one or two days to install) and materials such as a mounting system and cabling. Prices depend on quality of materials and the installation, so be very careful with only comparing on price. On average prices of around 1.500 pounds per kWp are normal, with discounts for larger systems due to installation efficiencies.

How much is the financial return?

Due to government incentives current yearly returns can be over 10% of initial investment. This means you will have paid back your system within 7-8 years, and can enjoy another 12 years of government incentives and free energy. Many people decide to go solar for financial reasons, as it currently returns more than ISA’s and bonds. Solar panels are considered a safe investment because their returns are inflation adjusted and tax-free.

How do I pick the right solar panels?

Because there are hundreds of solar panel manufacturers that create thousands of different panels this is a difficult choice. Key differences are efficiency (amount of energy generated per square meter), lifetime and aesthetics. Always verify the warranty terms on the proposed panels. Also check how large the manufacturer is, as you may need them 25 years from now to claim your warranty. Your solar installer can advise you further on the best choice of panels for your own roof.

How do I choose an installer?

The total price of the system, the price per Wp and the price per kWh generated are important measures – but be sure to also use qualitative criteria to select the right installer. Invite potential installers for a free and non-obligatory site visit to your house, so you can learn more. Installer certification, experience, quality of materials and warranty are good examples of important qualitative criteria (see solar education for more). Asking for relevant examples and customer references can help you to verify that your overall impression of this installer is right.

What does CompareMySolar do?

We make the orientation phase of going solar easy and accessible for all consumers. Our website takes you by the hand through the initial stage of the orientation, and provides information you need based on your own roof and locally available systems and installers. Before we connect you with your chosen installers we call you to answer any questions and give our personal advice. This allows for a thorough selection of installers for a non-obligatory site visit in your house, and prepares you to make an informed decision. After the site visit and the installation (if you choose to go solar) we will call you again to talk about your experience. This feedback helps installers to improve their service, and allows us to improve our website content for other users.