Choosing a solar installer in Wales

Local experience helps when a clear design, proven competence and reliable aftercare back it up. This guide shows how to check an installer before you sign. It covers MCS, consumer codes, written designs and the commercial terms that matter most.

Because Solar Cymru is an independent guide and enquiry service, we do not install. The checks below apply to every installer you meet, including those we refer.

Look for relevant experience

Ask for examples of similar roofs and homes. Ask how the installer handles the network process for your area, and who owns the paperwork. Also ask how they deal with Welsh planning questions, for instance a conservation area or a listed building.

Our post on MCS certification and your quote explains why the mark matters. Meanwhile, our planning permission guide lists the Welsh exceptions to raise.

Check MCS certification

MCS, the Microgeneration Certification Scheme, is the UK quality mark for small renewable systems. It certifies installers, products and installations. The solar standard, MIS 3002 issue 6.0, became mandatory for MCS contractors on 18 June 2026.

You need MCS certification to claim export payments on solar of 50 kW or less. A supplier may accept an equivalent scheme instead. A quote with a battery must say if the installer does not meet the battery standard, MIS 3012. Ask for the number and check it yourself.

Ask about consumer codes and protection

Joining a consumer code is no longer a condition of MCS. Under the redeveloped scheme it is optional, but installers can still join. All MCS installers must move to the new scheme by 31 March 2027.

Therefore, ask whether your installer belongs to a code, such as the Renewable Energy Consumer Code or HIES. Then ask how they protect your deposit and their workmanship. The redeveloped MCS scheme also requires an MCS-approved financial protection product. It gives at least six years of cover from installation, and it caps the claims excess at £250.

The Renewable Energy Consumer Code binds its members to written contracts and a cancellation period of at least 14 days. Deposits must stay reasonable, for example 15%, and never above 25%. Members also give a free workmanship guarantee of at least two years. HIES says its installers work under a code that the Chartered Trading Standards Institute approved.

Require a written design

A good proposal names the equipment, the layout and the way it works out yearly output. It lists the inputs, the shade check and the electrical work. It also lists what the price leaves out. Our solar yield guide explains the figures to expect.

MIS 3002 requires a performance estimate in a set format. It states orientation, inclination and a shade factor. It also warns that actual output can differ if the installer assessed your roof remotely, so ask how they checked yours.

Use the survey visit

The installer should look at your roof, meter and consumer unit. Ask them to explain each choice in plain words. Note anything they cannot answer, and ask for it in writing.

A clear answer is a good sign, because it shows they have done the work. A vague one is a reason to keep looking. Take your time, since you are not in a race.

Make the commercial checks

Confirm which company signs the contract with you. Ask how they protect your payments. Ask about subcontractors, warranties, fault repairs and complaints. Ask what happens if the design changes after the survey.

Compare prices on the same basis, because a cheap quote may leave out items. Our post on how much solar panels cost in Wales gives realistic ranges. Our page on solar panel installation lists what a quote should contain.

Check the building and electrical sign-off

An installer in a competent person scheme can certify Building Regulations compliance and notify the council. For electrical work, a scheme electrician arranges a compliance certificate within 30 days of completion. They also give an Electrical Installation Certificate. Ask for both at handover.

Warranties and lifespan

Panels should last 25 years or more. Premium panels often come with 25 to 30 year performance warranties. Meanwhile, an inverter usually needs replacing after about 12 years, and its warranty can start at five years. Ask who honours each warranty if the installer closes.

Watch for pressure and free offers

The Competition and Markets Authority publishes guidance on unfair commercial practices in sales and marketing. Take care with any offer that rushes you or hides the terms. Our post on free solar panels in Wales shows what to ask.

A roof lease can also affect a sale later, since most mortgage lenders require consent to any lease. That includes a lease of roof space. Our post on selling a house with solar panels covers the questions, and your conveyancer and lender can confirm your case.

How the Solar Cymru enquiry works

Our get quotes page lets you ask for quotes from MCS-certified installers. Solar Cymru passes your enquiry to them through the MoreLeadz lead system. The step is opt-in, so you decide whether to go ahead.

The referral does not replace your own checks. Compare at least two written quotes against the list above. For local detail, see our page on solar installers in Newport.