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This article has been reviewed and updated to reflect Ofgem's revised Typical Domestic Consumption Values, coming into effect on 1 July 2026.
As the days get longer, you might be wondering how much energy you could generate from those rays shining on your roof. Our head of solar, Scott Duncan, answers all the important questions you might have before deciding to install solar panels.
1. How do solar panels work?
Solar power uses a process called the photovoltaic effect, which turns the sun’s radiation into electricity.
Solar panels are made up of lots of photovoltaic cells containing silicon. When sunlight hits the silicon, it makes the electrons in them start moving around. This creates electricity that can be used to power our homes.
2. Does it matter what direction my roof faces?
Solar panels generate most electricity when they're on a south-facing roof that's sloped at 41º, and isn't shaded. It’s one of the first things our surveyors look at when checking your home’s right for solar. A good surveyor can talk you through how the panels’ position on your roof will affect their performance.
Solar systems that face southwest and southeast are only about 15% less efficient than ones on a south-facing roof. Systems on east and west-facing roofs still work, but they’re less effective. This is because they don’t get as much sunlight throughout the day.
3. What about feed-in tariffs?
Feed-in tariffs (also called FiT) were a government scheme. They paid people to generate their own green energy, and export it back to the National Grid. FiT closed in 2019, so it’s no longer available. But anyone who signed up before then should still get their 20 years of FiT payments.
The scheme has since been replaced by the Smart Export Guarantee (SEG) tariff. This rewards homes with solar based on how much renewable energy they export back to the grid. The rates vary depending on your electricity supplier. At OVO, we offer SEG rates of up to 20p per kWh.
4. Has solar technology improved in recent years?
Since 2010, average solar cell efficiency has increased from 15% to 22% – meaning a big jump in potential energy bill savings. There’s a few reasons for this improvement, including:
- Improved cell design that’s better at turning sunlight into electricity
- New, more efficient materials
- Better manufacturing processes
And then there’s batteries
More and more customers get a battery with their solar panels. Without one, you either use electricity as you generate it, or you export it back to the grid.
Getting a battery will add to the cost of your installation. But it means you can store energy, and use it later when you have more need for it. So if you’re out at work during the day, you can benefit from your panels when you’re home in the evening.
The financial case for batteries has improved for customers recently, too. Prices came down by 14% last year. OVO’s data shows that adding a battery can roughly double how much of your self-generated energy you can use.
5. Can solar panels really cut my energy bills?
Customers could save up to £1,065 a year on their bills with OVO's full solar package. This includes panels, batteries, inverters, and OVO's exclusive Smart Export Guarantee rate of up to 20p per kWh. From 1 July 2026, Ofgem's revised Typical Domestic Consumption Values reflect that UK households are genuinely using less energy than before — and against that updated benchmark, a typical home with OVO's solar and battery package can reduce their electricity bills by around 75%, with up to £575 a year in additional SEG export income on top.
We've heard lots of success stories from our customers. Like Robin Clapp from Wiltshire, who expects to make almost £1,200 back on his solar investment this year through exporting extra energy back to the grid with our 20p per kWh SEG rate.
6. Do I need a smart meter with solar panels?
You don’t have to have a smart meter to install solar panels. But you’ll need one if you want to take advantage of our 20p per kWh SEG rate.
If you get solar panels and a battery from OVO, and we supply your energy, you'll be eligible for this rate. To access it, you'll need to sign up to our SEG tariff and have a smart meter installed.
7. Will solar panels add value to my home?
According to Rightmove’s Greener Homes report, it’s worth installing green tech that increases your home's Energy Performance Certificate (EPC) rating – like solar panels. Boosting your rating from F to C, for example, can increase the value of your home by up to 15%.
For a 3-bedroom semi detached house, installing 10 solar panels would cost approximately £6,300. But they could add much more value than they cost. OVO’s data also shows that 66% of property buyers are prioritising green tech in their search for a home.2 Meaning there’s never been a better time to invest in things like solar panels.
8. Can I still sell power back to the grid?
According to our research, 45% of people don't know you can earn money by selling solar energy back to the National Grid.³ With solar panels and OVO's exclusive SEG rate of up to 20p per kWh, a typical system exporting around 2,875 kWh a year could generate up to £575 in annual export income — on top of the bill savings from self-consumption.
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1 These annual energy savings are dependent on your property type and location, roof type, slope, and size. If your roof is shaded or isn't south facing, figures are likely to be lower.
We based the figures on the following:
a) You have 12 x 440W solar panels and a 10kWh battery installed, generating 4,750 kWh per year.
b) Ofgem's medium Typical Domestic Consumption Value from 1 July 2026 is 2,500 kWh per year. The system covers 75% of this (1,875 kWh), with a remaining grid import of 625 kWh costing £163.19 per year, based on OVO's standard variable rate of 26.11p per kWh correct at 1 July 2026.
c) Annual bill saving: £489.56, representing a 75% reduction on a typical electricity bill.
d) You sign up for OVO's exclusive SEG Install Exclusive solar and battery rate of 20p per kWh. The remaining 2,875 kWh exported to the grid generates £575 per year in SEG income.
e) Total annual benefit: £1,065 per year.
You'll get a more accurate savings estimate once we've surveyed your property. Figures correct at 1 July 2026 and will be updated in line with Ofgem's quarterly price cap reviews.
2 Data from a consumer survey conducted by OnePoll, commissioned by OVO, with 2,000 UK nationally representative adults from 12 to 18 January 2024.
3 Data from a consumer survey conducted by OnePoll, commissioned by OVO, with 2,000 UK nationally representative adults from 7 to 13 July 2023.