Solar panels generate direct current (DC) electricity from sunlight, which your home cannot use directly.
Solar panels work by converting sunlight into electricity using photovoltaic (PV) cells. When sunlight hits these cells, it knocks electrons loose from their atoms, creating a flow of electricity.
Solar panels convert sunlight into DC electricity using photovoltaic cells. An inverter then changes it to AC for home use. Your home uses solar power first, and surplus exports to the grid under the Smart Export Guarantee (3p-15p per kWh).
- Solar panels use photovoltaic cells to convert sunlight into DC electricity.
- An inverter converts DC to AC for home use, typically in loft or garage.
- Your home uses solar power first; surplus exports to the National Grid.
- Smart Export Guarantee pays 3p-15p per kWh for exported electricity (Ofgem).
- System draws grid power at night or in heavy cloud automatically.
- Solar panels generate direct current (DC) electricity from sunlight, which your home cannot use directly.
- The inverter converts the DC electricity into usable AC electricity for your home.
- Your home uses the solar electricity first, and any surplus is exported to the grid.
- Quick numbers typical generation, savings, and payback for a UK home in 2026.
- Solar panels still generate electricity on cloudy and overcast UK days.
- Your installer must be MCS-certified and the system registered to qualify for SEG payments.
- How a solar panel system connects to your home's existing electrical infrastructure.
This flow is direct current (DC), the same type of electricity that flows from a battery. Your home’s appliances and the UK electricity grid run on alternating current (AC), which constantly changes direction. Because of this difference, the DC electricity from your panels must be converted into AC before it can power anything in your house. That conversion is handled by a device called an inverter, which is a standard part of every domestic solar panel system.
The inverter converts the DC electricity into usable AC electricity for your home.
The inverter is typically installed in your loft, garage, or on an exterior wall near your main consumer unit (fuse box). Modern systems use either a single “string inverter” for the whole array of panels, or microinverters attached to each individual panel. The inverter continuously adjusts to maximise power output as sunlight intensity changes throughout the day, ensuring you get the most electricity possible from your panels (Energy Saving Trust, 2026).
Your home uses the solar electricity first, and any surplus is exported to the grid.
When your panels generate more power than your home needs, the excess electricity automatically flows back into the National Grid. Under the Smart Export Guarantee (SEG), your electricity supplier must pay you for every kilowatt-hour (kWh) you export. Typical SEG rates in 2026 range from 3p to 15p per kWh, depending on your supplier (Ofgem, 2026). When your panels aren’t generating, such as at night or in heavy cloud, your home seamlessly draws power from the grid as usual.
Quick numbers typical generation, savings, and payback for a UK home in 2026.
| Item | Typical value | Notes |
|---|---|---|
| Typical system size | 4 kWp (kilowatt-peak) | ~10–12 panels |
| Annual generation (South-facing, no shading) | ~4,200 kWh per year | Energy Saving Trust, 2026 |
| Annual generation (East/West split) | ~3,600 kWh per year | Energy Saving Trust, 2026 |
| Typical annual electricity bill saving | £350–£600 | Energy Saving Trust, 2026, based on Oct 2026 price cap |
| Typical SEG export income | £100–£200 per year | Ofgem, 2026; Energy Saving Trust, 2026 |
| Typical installed cost (2026) | £5,000–£7,000 | MCS, 2026; Energy Saving Trust, 2026 |
| Typical payback period | 9–14 years | Energy Saving Trust, 2026 |
Solar panels still generate electricity on cloudy and overcast UK days.
PV cells respond to diffuse daylight, not just direct sunshine, so they produce power even under thick cloud cover. A 4 kWp system on a typical cloudy winter day can generate 3–8 kWh, enough to run a fridge, lights, and a TV. Generation drops significantly in winter because of shorter daylight hours and a lower sun angle, not just cloud cover (Energy Saving Trust, 2026).
Your installer must be MCS-certified and the system registered to qualify for SEG payments.
MCS (Microgeneration Certification Scheme) certifies both the installer company and the specific solar panel products used. Without MCS certification, you cannot receive SEG payments from your supplier for exported electricity. You should also check the installer holds TrustMark registration for consumer protection standards (TrustMark, 2026). After installation, the installer must register the system on the MCS database and provide you with a certificate of compliance.
How a solar panel system connects to your home’s existing electrical infrastructure.
The inverter feeds AC electricity into a dedicated circuit that connects to your consumer unit (fuse box). A generation meter, supplied by the installer, is fitted between the inverter and the consumer unit to measure total output. Your existing electricity meter is not replaced, but your supplier may install a smart meter to record exports for SEG payments. The system is isolated by a dedicated switch (AC isolator) so an electrician can safely work on your home wiring.
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Frequently Asked Questions
Solar panels do not generate electricity at night because they need sunlight. Your home automatically draws power from the National Grid, and you can add battery storage to use daytime surplus after dark (Energy Saving Trust, 2026).
Solar panels still generate electricity in winter, but output is lower due to shorter days and weaker sunlight. They can produce 10-25% of summer levels, depending on location and weather (Energy Saving Trust, 2026).
A solar inverter converts DC electricity from panels into AC electricity for your home. It also optimises power output as sunlight changes and is a mandatory part of every UK solar system (MCS, 2026).
Solar panels connect to the National Grid through your home's consumer unit via an inverter. Any surplus electricity flows back to the grid automatically, and you get paid under the Smart Export Guarantee (Ofgem, 2026).
Yes, solar panels still generate electricity in cloudy weather, though at reduced output (typically 10-25% of sunny conditions). Modern panels capture diffuse light effectively (Energy Saving Trust, 2026).
