How Solar Panels Work
Solar PV (photovoltaic) panels generate electricity from light. Each panel contains silicon cells that release electrons when struck by photons from the sun, creating a flow of direct current (DC) electricity. The more light that falls on the cells, the more electricity they produce.
A device called an inverter — usually fitted in your loft or utility room — converts that DC electricity into the alternating current (AC) your home appliances use. From there, electricity flows into your consumer unit just as it would from the grid, powering your lights, boiler, appliances, and anything else you have running.
Any electricity your panels generate that you do not immediately use can either be exported to the national grid (earning you money via the Smart Export Guarantee) or stored in a home battery for use later in the day or overnight. Importantly, solar panels work on daylight, not direct sunlight — they still generate electricity on overcast or cloudy days, simply at a reduced output.
Types of Solar Panels
Monocrystalline
Made from single-crystal silicon, these panels are the most efficient on the market. They have a sleek, uniform dark appearance and perform best in limited roof space. Higher manufacturing cost, but prices have fallen significantly.
Appearance: Uniform black
Polycrystalline
Manufactured from multiple silicon crystals, these panels have a recognisable blue-speckled appearance. Slightly less efficient than monocrystalline but cheaper to produce. A good value option if you have a larger roof area.
Appearance: Blue tint, speckled
Thin-film
Deposited in thin layers onto glass, metal or plastic — making them flexible and lightweight. Lower efficiency means they need more surface area for the same output. Primarily used in commercial, industrial and specialist applications.
Appearance: Flat, uniform, flexible
2026 recommendation: The majority of UK homeowners choose monocrystalline panels. Prices have dropped considerably over the past five years, making the efficiency advantage well worth the modest cost premium — particularly on smaller roofs where maximising output per square metre matters most.
Is My Home Suitable for Solar Panels?
Most UK homes are suitable for solar panels, but output and viability depend on several factors. Use the checklist below to get a quick sense of how well your property is likely to perform.
Good indicators
Worth checking
Not sure? A free home survey from an MCS-certified installer is the most reliable way to assess suitability. They will check orientation, pitch, shading, and roof condition in person.
Why MCS Certification Matters
The Microgeneration Certification Scheme (MCS) is the UK industry standard for the design and installation of solar PV systems. It is operated independently of government and sets minimum standards for both products and installation quality.
Using an MCS-certified installer is not optional if you want to unlock the financial and regulatory benefits of solar in the UK. Always ask to see your installer's current MCS certificate number and check it on the MCS register at mcscertified.com.
What MCS certification gives you
MCS certification is a mandatory requirement to register for SEG payments from your energy supplier.
ECO4 and the Home Energy Scotland Grant both require MCS-certified installers. Without it, installations are ineligible.
MCS-certified installers are required to provide a 10-year warranty on their installation workmanship, separate from the manufacturer's panel warranty.
MCS installers must follow a code of practice, giving you a formal complaints route if something goes wrong.
The Solar Panel Installation Process
From enquiry to your first SEG payment, here is what to expect at each stage of a typical residential solar installation in the UK.
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Home survey (free, 30–60 minutes)
An installer visits your property to assess your roof orientation, pitch, condition, and shading. They will review your recent electricity bills to understand your usage patterns and recommend the most appropriate system size.
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Quote and system design
You receive a detailed proposal showing the projected annual output (in kWh), expected bill savings, export income, total cost, and estimated payback period. A good installer will model this for your specific property and consumption profile.
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Scaffolding erection (1–2 days before install)
A scaffolding contractor erects safe working platforms around the roof. This usually happens a day or two before the solar installation team arrives. The scaffold remains in place until the system has been signed off.
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Panel installation (1–2 days)
The installation team mounts rails and brackets to your roof structure, then fits the solar panels. The inverter is installed indoors — typically in the loft, garage, or utility room — and cabling is routed from the roof to the consumer unit.
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Electrical testing and sign-off
The completed installation is tested by a Part P registered electrician. An Electrical Installation Certificate (EIC) is issued. The system is commissioned and you are shown how to monitor its output.
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MCS certificate issued
Your installer registers the installation with MCS and issues your MCS certificate. Keep this document safe — you will need it when registering for the Smart Export Guarantee and it may be requested when you sell your home.
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Scaffolding removal (1–3 days after completion)
Once installation and testing are complete, the scaffold is struck and removed. The total disruption to your property is usually just a few days.
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SEG registration
Contact your energy supplier with your MCS certificate number and apply for a Smart Export Guarantee tariff. Your supplier is legally required to offer you one if you are eligible. Once registered, you will be paid for every kWh you export to the grid.
Plug-in Solar Panels
Plug-in solar — also called balcony solar, micro-inverter panels, or PVRS (plug-in renewable systems) — is one of the fastest-growing segments of the UK solar market in 2026. These are small systems, typically 200 W to 800 W, that connect directly to a standard 13 A socket and feed electricity into your home's circuits without professional installation.
They are available from a growing range of retailers including Lidl, Amazon, and specialist solar suppliers. Prices for a single-panel 400 W system typically start at around £200–£400 all-in.
Output is limited by the single-socket connection and system size. In a typical UK location, a 400 W plug-in system might save £80–£150 per year on electricity bills, depending on how well its generation profile matches your daytime consumption.
Key things to know
No MCS certification or professional electrician required — you install it yourself
Suitable for renters, flats, and people who want to test solar before committing to a full installation
Can be mounted on a balcony railing, south-facing wall, flat roof, or in a garden
Not eligible for the Smart Export Guarantee — exported electricity is not metered or paid
Check with your energy supplier and local Distribution Network Operator (DNO) before installing — some suppliers require notification for systems above 800 W
Best for: Renters, flat-dwellers, homeowners testing solar ahead of a full installation, and anyone who wants the lowest-cost entry point into generating their own electricity. For homeowners who own their property, a full rooftop installation will almost always deliver better returns.