How Much Do Solar Panels Save in the UK?
Author: Steve Fairless
Originally Published: 18th January 2024 · Updated: 3rd September 2026
Solar savings are not a fixed percentage of your electricity bill. They come from two different values: electricity you generate and use instead of buying from the grid, plus any payment you receive for electricity exported. The strongest result normally comes from matching generation to your own demand rather than assuming every solar kWh is worth the same amount.
At Sustainable Energy Engineering, we model savings from the property itself: annual electricity use, daytime demand, roof orientation, shading, system size, battery strategy and tariff. That is much more reliable than promising a generic annual saving.
Current independent guidance suggests domestic solar can commonly pay back over roughly 9 to 12 years in example UK locations when export payments are included, but an individual home can perform better or worse than those examples.
For a system-specific estimate, we design through our domestic solar PV service and can include battery storage where shifting energy into the evening makes sense. We also explain available export options through our energy tariff guidance.
Updated: 3rd September 2026
Solar Savings: The Short Answer
- The saving depends on how many solar kWh replace imported electricity. Self-consumed solar is usually more valuable than simply exporting the same unit.
- Export income is additional, but there is no single permanent SEG rate. Suppliers set their own rates and terms.
- Current Ofgem average capped electricity unit rates are around 26.11p/kWh for Direct Debit customers from July to September 2026. Actual tariffs vary.
- Battery storage can increase self-consumption, but the battery cost and conversion losses must be included in the economics.
- A credible saving forecast should show its assumptions. We do not present an annual saving as a guarantee.
Where Solar Savings Actually Come From
A solar system can create financial value in three main ways: avoiding grid imports when generation is used on-site, receiving export payments for surplus electricity, and changing when electricity is imported if battery storage and a time-of-use tariff are used.
| Energy flow | Financial effect |
|---|---|
| Solar used immediately | Avoids buying that electricity from the grid at the applicable import rate. |
| Solar stored and used later | Can avoid later grid imports, after allowing for battery losses and capacity limits. |
| Surplus exported | Can earn an export payment under a suitable tariff. |
| Battery charged cheaply from grid | Can shift lower-cost electricity into a more expensive period where tariff terms allow. |
Why Self-Consumption Matters More Than a Headline Generation Figure
Suppose two homes each generate 4,000 kWh in a year. The first home uses a large proportion during the day; the second exports most of it because nobody is home. Their solar generation is identical, but the bill saving can be different because avoided import and export are priced differently.
That is why we ask when electricity is used, not only how much is used over a year. Smart-meter half-hourly data is extremely useful because it shows the actual load profile we are trying to match.
A Simple Worked Example
At an electricity import rate of 26.11p/kWh, using 2,000 kWh of your own solar instead of importing it represents about £522 of avoided electricity purchase before considering standing charges, export income or tariff changes. This is a worked illustration, not a forecast for a specific home.
What Is Electricity Worth in September 2026?
For the current July to September 2026 price-cap period, Ofgem publishes an average Direct Debit electricity unit rate of 26.11p/kWh across England, Scotland and Wales for customers on standard variable tariffs. Your actual rate can differ by region, payment method and tariff, and fixed or smart tariffs can be very different.
We therefore update the import rate used in a financial model rather than relying on a historical national average.
How Export Payments Change the Calculation
The Smart Export Guarantee requires participating suppliers to offer eligible generators a payment for exported electricity, but suppliers decide their own rate, contract length and terms. The export supplier does not have to be the same company that supplies your imported electricity.
We treat export income as a variable rather than assuming one supplier rate will last for the lifetime of the system. A robust design should still make sense if tariffs change.
What Do Current Payback Examples Show?
Energy Saving Trust example calculations updated for 2026 show solar payback periods with export payments of around 9 to 12 years across example locations and occupancy patterns. Those figures are useful context, but they are not a promise for every property. Roof orientation, shading, installed cost, tariff, system size and electricity use all alter the result.
A shorter claimed payback is not automatically a better quote if it has been achieved by assuming unrealistic electricity-price inflation, unusually high self-consumption or a generous export tariff for decades.
How We Estimate Annual Solar Savings
- Estimate annual generation from installed kWp, location, orientation, inclination and shading.
- Estimate self-consumption using the household load profile and whether storage is included.
- Value self-consumed energy using a realistic import tariff.
- Value exports using a clearly stated export assumption.
- Include battery losses and limits where storage is modelled.
- Keep future price assumptions separate from first-year savings so the customer can see what drives the result.
Why MCS Performance Estimates Are Not Guarantees
MCS requires a standard performance estimate and expressly states that solar output cannot be predicted with certainty because solar radiation varies by location and from year to year. The same principle applies to savings: weather, household behaviour and tariffs all change.
We use forecasts as decision tools. We do not present a first-year model as a contractual guarantee of what a future electricity bill will be.
Does Battery Storage Increase Solar Savings?
A battery can increase the proportion of solar used on-site by moving daytime surplus into the evening. It may also make a time-of-use tariff more valuable. However, batteries have an upfront cost, finite life and conversion losses, so a larger annual bill saving does not automatically mean a better whole-life financial return.
We compare solar-only and solar-plus-storage outcomes where appropriate so customers can see what the battery adds rather than assuming it is always essential.
How Future Loads Can Improve Solar Utilisation
An EV, heat pump, electric hot-water diverter or home-working pattern can change the value of solar because there is more electricity demand to match. If those loads are planned, we would rather design for them now than size a system solely from last year s bill.
That does not mean simply installing the largest array possible. Network limits, roof area, seasonal generation and export value still need to be considered.
Our Recommendation on Solar Savings Claims
Ask any installer to show the assumptions behind the saving. You should be able to see the expected annual kWh, the self-consumption assumption, the import price, the export price and whether battery losses are included. If a payback figure cannot be explained, it is not useful enough to base an investment decision on.
Want a Solar Saving Estimate Based on Your Home?
Give us your annual electricity use and, where possible, smart-meter data. We can design the system around real demand and show how generation, self-consumption and export contribute to the forecast.
Request a tailored quote from Sustainable Energy Engineering.
