Frequently Asked Questions

How do solar PV panels generate electricity?

Solar panels generate electricity using the sun’s energy, producing energy from daylight not direct sunlight, so they can still produce energy on a cloudy day. Although more power is generated when the sun is stronger, and shade is to be avoided.

An inverter converts the electricity from direct to alternating current for use in the home. It can either be used directly in the home, or when the system is generating more power than is needed, it is exported to the National Grid.

What happens at night?

At night, as the solar panels are not generating electricity, power is imported from the grid in the normal way and you buy your electricity from your energy supplier.

The system does not consume power at night.

What happens if there is a power cut?

Solar PV systems are connected to the National Grid, if there is a power cut, the system is automatically switched off. This is a safety precaution designed to protect those working on restoring power and to stop electricity leaking onto the National Grid.

Is my roof suitable?

The optimum orientation for solar panels to have the highest output in the UK is to have them south facing at a 30-40 slope, with little or no shading. A sloping roof will be suitable as long as it faces south, south-east, south-west or anything between east or west. If your roof is north facing, it will still generate power, but probably not enough to justify the financial investment.

How are the panels installed?

There is a choice of an ‘in roof’ system, where the tiles are replaced or an ‘on roof’ system, which sit on roof hooks above the tiles. Neither system will damage the integrity of the roof.

Do I need planning permission?

Solar roof systems fall under ‘permitted development’ rights, defined by panels projecting no more than 200mm from the roof structure, therefore most domestic properties do not require planning permission prior to installation.

However, if your installation is on a non-residential property, flat roof, listed buildings and within a Conservation Area, Area of Outstanding Natural Beauty or World Heritage site you must consult the local planning authority.

What size PV system do I need?

This ultimately depends on your available roof space, energy output and budget. Most systems installed are between 2-3kWp, generating between 1,750-2,400kW per annum. The best Feed-In Tariff is available for systems up to 4kWp.

What is the difference between a kilowatt hour (kWh) and a kilowatt peak (kWp)?

A kilowatt hour is the same as a ‘unit’ of energy on your bill and a kilowatt peak refers to the value of power generated by a solar panel system under full solar radiation (under set Standard Test Conditions). Solar radiation of 1,000 watts per m is used to define standard conditions. For example, in the UK overall, 1 kilowatt peak (kWp) will generate approximately 850 kilowatt hours (kWh) per annum. In South Wales, the average is 950 kilowatt hours (kWh) per annum.

Can I install a PV system myself and have an electrician connect it to the National Grid?

In order for your system to qualify for Feed-In Tariffs, it must be installed by an accredited MCS Installer. CECsolar is an MCS accredited installer and will provide you with a certificate after installation. You will need this certification in order to sign up to the National Grid.

What if I move house?

When you install Solar PV and start claiming the Feed-In Tariff, your energy costs are instantly lowered and you will receive a steady income from the FiT payments. When you come to sell your house, these benefits are transferred to the new owner, enabling you take this remuneration into account upon valuation.

Where does the money for the Feed-In Tariff come from?

You are already paying for the Feed-In Tariff through your energy bills whether you have a Solar PV system or not. The money used to pay the producers of green energy comes from a small levy on every UK energy consumer. By installing a PV system, it is a way of reclaiming your contribution, whilst making a profit.

Do I require a energy Performance Certificate (EPC)?

For any installation completed after the 1st of April 2012 an energy performance certificate of a grade D rating or above would be required to entitle you to apply for the Feed in Tariff, please contact us for further information

Solar PV Panels being installed by CEC Solar
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Did you know?

The Photovoltaic principle was first discovered in 1839 by the French physicist Alexandre-Edmond Becquerel. Although it was Charles Fritts, an American inventor who built the first photovoltaic cell in 1883.