Solar PV & battery storage
Solar Panel Installation in Cardiff & Caerphilly
Rooftop solar and home batteries, surveyed, installed and certified by the same electricians who look after the rest of your wiring.
- NICEIC registered
- Certified & notified work
- Free quotations
Is your roof worth it?
A south-facing roof is the ideal, but east and west roofs work well too — they simply spread the generation across the morning and afternoon instead of peaking at midday. What matters more than people expect is shading. A chimney, a neighbour's extension or a tree that throws a shadow across one row of panels for part of the day can pull down the output of the whole string unless the system is designed around it.
Panels generate from daylight, not just from sunshine, so a grey Welsh day still produces something. Output is much lower in winter, which is why the honest way to judge a system is by what it makes across a year, not on a bright day in June.
The other thing a survey looks at is your own pattern of use. Solar makes most of its power in the middle of the day, which is when many households use the least. That gap is what a battery, a solar-aware EV charger or an export tariff is there to close.
What an installation involves
We start with a survey: the roof, its orientation and shading, the loft, the consumer unit and the incoming supply. That tells us how many panels make sense, where the inverter can go and whether the consumer unit has room for the new circuit or needs work first.
On the day, the panels go onto rails fixed to the roof structure — scaffolding is normally needed for that — and the cables come down to the inverter, which turns the panels' DC into the AC your home uses. The inverter is connected to the consumer unit on its own circuit, with isolation on both sides so the system can be switched off safely for maintenance, and a generation meter so you can see what it is producing.
A new circuit is notifiable work, so you get an Electrical Installation Certificate for it and the building regulations compliance certificate follows through our scheme. The rules on signing work off are different in Wales from England; we set them out in what electrical work needs signing off in Wales.
Telling the network operator
Anything that can feed power back into the grid has to be declared to the local distribution network operator, which across South Wales is National Grid Electricity Distribution. Smaller systems — up to 16 amps per phase, roughly 3.68kW on an ordinary single-phase house supply — are notified under what is called G98 within 28 days of commissioning.
Larger systems, or a system whose panels and battery together push the inverter capacity over that limit, come under G99, which means applying and getting the network operator's agreement before the system is installed. It is worth knowing at the planning stage, because it affects how a battery is sized and connected. We deal with the paperwork either way.
Adding a battery
A battery stores the daytime surplus and gives it back in the evening, which is when most homes actually use their power. It can go in at the same time as the panels with a hybrid inverter, or be added later to an existing system with its own inverter.
Where the battery goes matters. Manufacturers set conditions on location, ventilation and clearances, and we plan the position at survey rather than finding a corner on the day.
One thing that surprises people: an ordinary grid-connected solar system switches itself off in a power cut. That is deliberate — it stops the system feeding a line that engineers believe is dead. Running the house from a battery in a power cut needs a system designed for backup, with the right inverter and an automatic changeover, so say so at survey if that matters to you.
Getting paid for what you export
Under the Smart Export Guarantee, larger electricity suppliers have to offer a tariff for the power you send back to the grid. The rates vary a great deal between suppliers and you do not have to take the one from your existing supplier.
Most suppliers ask for an MCS certificate for the installation before they will pay an export tariff. If an export tariff is part of your sums, raise it at the quote stage so the paperwork you end up with matches the tariff you want.
Planning permission
Panels on the roof of a house are usually permitted development, but there are conditions, and listed buildings, conservation areas and flats are treated differently. Planning and the electrical sign-off are separate things. If the house is in a conservation area — and parts of Penarth, Llandaff and Rhiwbina are — check with the council before committing.
Questions
Frequently asked questions
Do solar panels work in Welsh weather?
Yes. They generate from daylight, so an overcast day still produces power, just less of it. Winter output is far lower than summer, which is why a system should be judged on what it makes across the year.
I already have an EV charger. Can solar work with it?
Usually, and well. Several chargers can follow your solar output so the car soaks up what would otherwise be exported. We check the supply and the consumer unit can carry both before quoting. See our EV charging page for the charger side.
Will I need a new consumer unit?
Not always. The inverter needs its own circuit with suitable protection, and the survey tells us whether the existing board can take it. If it cannot, we will say why rather than assume a replacement.
Will the panels keep my lights on in a power cut?
A standard grid-connected system will not — it shuts down when the grid goes off, by design. Backup needs a battery and inverter set up for it with an automatic changeover, so ask for it at the survey if you want it.
Free quotes
Thinking about solar?
Send us the address and a photo of the roof, and we will arrange a survey.