Solar PV Frequently Asked Questions

Some text about how simple the process is with the installation of the system and how long it takes to install the system to your property.

What are Photovoltaic (PV) Panels?

PV cells are panels you can attach to your roof or walls. 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 look like roof tiles to panels and transparent cells that you can use on conservatories and glass.

How are PV panels fitted?

Photovoltaic panels can be mounted on a roof or ground mounted. Ideally the roof will be south facing, or near to at an angle of 30 degrees with the horizontal for optimum performance. The panels produce DC electricity, so a small inverter will be fitted inside the house, to change the DC into AC (used in all normal homes and the Grid). Installation is clean, with minimal disruption and no extra space needed indoors.

How many are needed?

Any number of PV panels can be connected based on available space, to provide as much electricity output as required. A basic 2kWp solar panel installation will generate around 1500 kWh per year.

Which roof should they go on?

The optimum orientation for solar photovoltaic panels is due south at a 30 degree latitude tilt in the UK. Systems facing East or West will lose efficiency but are still viable. Systems such as solar trackers maximise exposure to the sun by following it's path. This will increase efficiency by 20% during the winter and up to 50% during summer over static systems.

Will it supply all my electricity?

The average household consumption is 3,300 kWh per year. The 2kWp system would supply nearly 50% of annual consumption. A 4 kWp system could provide all electricity needs depending on consumption for the average household.

What size system do I need?

This depends on your budget, available roof space (unless ground mounted) and energy output required.

What Maintenance is required?

As there are no moving parts in the PV panels, there is no noise or need for maintenance other than an occasional clean as required. Solar panels come with a warranty of over 20 years.

Is Planning Permission Required?

Most properties in England and Scotland do not require planning permission before installation of photovoltaic solar panels. Those in Conservation Areas, listed buildings and Areas of Outstanding Natural Beauty or World Heritage Areas must consult local Planning Departments.

How long does the installation process take?

PV systems can be installed and ready to produce green electricity within 6 weeks after the design agreement between householders and installer has been made. For commercial PV installations, we can work within required deadlines as necessary.

Can I really sell back to the National Grid?

Yes. The April 2010 Feed-in Tariff will pay a premium on every unit of electricity generated by PV panels with an additional bonus for every unit of electricity exported back to the National Grid. This Tariff will be administered by Ofgem. Electricity suppliers will be responsible for paying the reward to customers.

What is the Feed-in Tariff?

If you install an electricity-generating technology from a renewable or low-carbon source such as solar PV or wind turbine, the government's Feed-In Tariff scheme (FIT) could mean you get money from your energy supplier.

You can be paid for the electricity you generate, even if you use it yourself, and for any surplus electricity you export to the grid. And of course you'll also save money on your electricity bill, because you'll be using your own electricity.

Do PV Panels Work In The UK?

Generally temperatures above room temperature reduce the efficiency of PV solar panels, making the UK a good climate for photovoltaic technology. The panels require ambient light rather than direct sunlight to generate electricity so they work even on overcast days.


Solar PV calculator provided courtesy of Solar Guide, the UK's leading resource of MCS accredited solar PV installers and solar thermal companies.