How do solar panels work? A simple guide for UK Homes
Learn how solar energy becomes clean, green electricity that powers UK homes.
Solar panels create electricity by converting daylight into usable energy for your home using photovoltaic technology. When sunlight hits the panels, it creates an electrical current that is transformed into usable power through an inverter, helping you reduce reliance on the grid.
What Are Solar Panels?
Solar panels are made from photovoltaic (PV) cells, usually silicon-based materials that react when exposed to light. These cells create an electrical current without moving parts.
How do solar panels work?
Step 1: Solar panels absorb energy from daylight.
Solar panels are made up of photovoltaic (PV) cells, which capture energy from sunlight.
Step 2: The cells create an electric current.
Inside each solar panel, PV cells sit between layers of semi-conducting materials, usually silicon. When sunlight hits the cells, it energises them and creates an electric field.
Step 3: Direct current (DC) electricity is generated.
This process is known as the photoelectric effect. It creates a flow of electricity called direct current (DC).
Step 4: The electricity is converted for use.
The electricity then passes through an inverter, which converts it into alternating current (AC) — the type of electricity used to power homes and businesses.
Step 5: The energy powers your property or goes back to the grid.
Once converted, the electricity can be used in your home or business. Any excess electricity can be exported to the grid, or stored in a battery if you have one installed.
Watch this video on how solar panels work for more insight
What are some of the benefits of solar panels?
There is 18.1GW of installed solar in the UK – that’s more than four times the capacity of Britain’s largest fossil fuel power station.
Solar panels can be installed in a wide range of places. From larger, countryside solar farms that can support local biodiversity by providing an undisturbed habitat for bees, butterflies and nesting birds, to rooftop solar panels in city centres that can help combat fuel poverty.
Solar panels don’t create any noise pollution while generating electricity. This means that installations aren’t intrusive – whether they’re in crowded urban locations or quiet rural ones.
Solar panels are very safe. They’re mostly made from silicon sheets, and there’s no danger of the photovoltaic cells leaking or emitting any toxins or fumes.
Solar panels help you to cut your carbon footprint, and will pay for themselves through savings in your bills in an average of 10 years.
Solar panels are one of the most effective ways to cut your monthly bills.
Find out more about solar panels
How do solar panels work FAQs
Yes. While output is higher on bright, sunny days – solar panels generate electricity from daylight rather than direct sunshine, so they can still produce power on cloudy days.
One Good Energy customer, Steve, used to think that conditions needed to be optimal for solar panels to work properly in the UK. But, after installing his solar and battery system in winter, he was surprised that “from the very first month our solar panels and battery have covered most of what we are using at home.”
Read Steve’s full story: Steve’s story: Solar panels and Tesla Powerwall | Good Energy
Solar panels typically last 25–30 years or more, meaning you can save on your energy bills for decades by generating your own cleaner electricity. What’s more, Good Energy solar installations are backed by 25 year product warranties, giving you long-term confidence in your system’s safety and performance.
Get a free personalised quote to see how much you could save.
Solar panels require very little maintenance. Occasional cleaning to ensure panels aren’t obstructed by dirt, debris or heavy shading is best practice to keep them performing efficiently.
Many modern systems, including the optimised systems we install at Good Energy, also come with an app that lets you see how each panel is performing. This makes it easy to spot if one panel isn’t generating as expected – something that’s much harder to identify with traditional string inverter systems, where all panels are monitored together.
Learn more: Optimised vs String solar panels: which is better?
In most cases, no. Solar panels are usually considered permitted development in the UK, meaning you can install them without planning permission as long as certain conditions are met.
However, permission may be required if your home is listed or in a conservation area. Good Energy’s solar experts are experienced in guiding homeowners through these requirements, and have designed many systems to complies with local regulations.
For example, in one conservation-area installation in Sevenoaks, our team sourced custom-coloured solar panels to match the home’s roof tiles, allowing the system to comply with council guidelines while still generating clean electricity.
Read the full case study: Mary’s story: Solar panels in a conservation area
Your savings will depend on your system size, how you use power, your tariff rates and more. An average 3-bedroom home with a 10-panel (4.75kW) solar array could save up to £975.90 a year through reduced grid usage and earnings from a our Solar Savings export tariff, or up to £1448.79 with a battery.
Total annual bill savings are based on standard MCS calculations for a 10-panel (4.75kWp) solar system on a 3-bedroom East/West-facing home with no shading. System estimated to generate 4,822kWh per year, of which 2,000kWh is used at home, reducing electricity bought from the grid, and 2,822kWh exported at 15p/kWh through Good Energy’s Solar Savings tariff. Actual savings may vary depending on system size, tariff rates and household electricity use. Solar packages start from £6,250 (including installation). Price varies by property and system specification. See our full workings here.
Additionally, if you install your solar panels and battery through Good Energy, you unlock our highly-competitive export tariff (25p per kWh) for the first 12 months, meaning savings for the same 3-bedroom home with a 10-panel (4.75kW) solar array and battery could save up to £1,730.99 in the first year.
Solar panel installation is quick and, for most homes, can usually be completed in a single day. Scaffolding is typically installed a couple of days before the work begins and removed shortly after the installation is finished.
Installation times can vary depending on factors such as the system size, roof complexity, weather conditions, and whether a battery system is included. Your installer will confirm the expected installation timeframe during your survey.
We’ll design the right system for your home and your needs, to help you achieve a quicker return on investment.
Our proposal data shows that most homes can achieve ROI within eight years, and over 40% can achieve it in as little as seven years.
Based on modelling from 157 Good Energy domestic solar proposals. Payback varies by property. Read how we’ve worked that out here.
Solar panels are suitable for most roofs in the UK. While south-facing roofs typically generate the most electricity, east-, west- and even north-facing roofs can still work well depending on your roof space and energy needs.
For example, one Good Energy customer, Richard, installed panels on a north-facing roof to maximise the space available, and his panels are helping generate extra electricity to power things like hot water and electric vehicle charging at home.
Click here to read Richards story: Installing solar panels on a north-facing roof
Commercial solar panels work in the same way as residential systems. Solar panels contain photovoltaic (PV) cells that convert sunlight into electricity, which is then passed through an inverter to make it usable for a building’s electrical systems. Businesses typically install larger systems on rooftops or nearby land so they can generate clean electricity on-site and reduce their reliance on grid power.
Interested in solar panels for your business? Learn what’s involved in commercial solar panel installation here.
Want to see how businesses are using solar to reduce overheads and increase resilience? Browse our case studies here.
Alternatively, you can call us on 0345 034 0755. Our experts are available on weekdays from 9am-5pm, excluding bank holidays.
* Based on modelling from 157 Good Energy domestic solar proposals. Payback varies by property. For more information on how we calculate our solar savings, please visit: goodenergy.co.uk/solar-panel-savings.