With energy costs continuing to be an important consideration for UK households, more homeowners are looking at ways to reduce their reliance on electricity from the grid.
Solar energy has long been one of the most popular options, but a new UK study has provided particularly interesting real-world evidence of what can happen when Solar Panels are combined with home battery storage.
Published by Centre for Net Zero on 28 September 2026, the research examined 708 households taking part in a randomised controlled trial. Rather than relying purely on projections or computer modelling, researchers were able to analyse actual smart-meter data from participating homes.
The findings were significant. Households receiving solar PV and battery storage saw electricity bills fall by around 62% on average, equivalent to approximately £681 per year during the study.
But reducing bills wasn’t the only finding. The technology also substantially reduced the amount of electricity households needed from the grid, particularly during periods of peak demand.
What Did the UK Solar and Battery Trial Involve?
The research was conducted by Centre for Net Zero in collaboration with Octopus Energy.
The trial involved 708 households participating in Great Britain’s Warm Home Discount Scheme, with households receiving solar panels and battery storage.
This is an important aspect of the research because much of the existing evidence surrounding residential solar has historically come from early adopters. The researchers wanted to establish stronger causal evidence of what happens when households actually receive solar and battery technology.
Using real-world electricity consumption data allowed researchers to measure changes in household energy use, electricity bills and demand on the wider grid.
Electricity Bills Fell by Around 62%
One of the headline findings was the impact on household electricity costs.
Following the installation of solar and battery technology, electricity bills were reduced by approximately 62%, or £681 per year, according to the study.
The largest savings occurred during summer, when solar generation is naturally at its highest, with estimated electricity bills falling close to zero for some periods. Importantly, however, savings continued during the winter months too.
The principle behind the savings is relatively straightforward.
Solar PV allows a property to generate electricity during daylight hours. Electricity generated by the system can be used within the home rather than purchasing the equivalent electricity from the grid.
When a battery is added, surplus electricity can also be stored and used later.
Instead of unused solar generation immediately being exported, some of that electricity can be retained for times when household demand is higher or solar generation has fallen.
Net Electricity Imported From the Grid Fell by 77%
The research also demonstrated how significantly solar and batteries can change a property’s relationship with the electricity grid.
Households reduced their direct draw of grid electricity by 38%. Once electricity exported back to the grid was taken into account, their net electricity imports fell by 77%.
This highlights an important distinction when considering residential solar.
The benefit isn’t simply the amount of electricity generated on the roof. How and when that electricity is used can also make a substantial difference.
A household capable of generating, storing and using more of its own electricity can reduce the amount it needs to import from the grid.
Battery Storage Made a Measurable Difference
Another particularly useful part of the study was the researchers’ ability to estimate the contribution made specifically by battery storage.
The battery was estimated to be worth approximately £148 per year, equivalent to around 13% of the baseline electricity bill in the study.
A home battery can store electricity generated during periods when household consumption is relatively low and make it available later.
For example, a solar system may generate substantial electricity around midday while nobody is home. Household electricity consumption may then increase considerably during the evening.
Without storage, much of that surplus daytime generation could be exported.
With Solar Batteries, some can instead be stored for use when it is needed.
The exact financial benefit of a battery will naturally vary depending on factors including household electricity consumption, system size, solar generation, electricity tariff and how the battery is managed.
Peak-Time Grid Demand Fell by 66%
The research wasn’t only concerned with household bills.
One of its most interesting findings involved electricity consumption between 4pm and 8pm, when demand on the electricity network is typically much greater.
Among participating households, grid imports during this period fell by 66%.
Perhaps even more interestingly, the researchers found that this load-shifting effect continued into December, despite there being relatively little solar electricity available to store during the winter.
This demonstrates one of the wider potential benefits of residential battery technology.
If electricity demand can be moved away from the busiest periods of the day across large numbers of properties, residential energy technology has the potential to contribute not only to household savings but also to reducing pressure on the wider electricity system.
Your Electricity Tariff Matters Too
Installing the technology is only one part of the equation.
The trial also found that electricity tariffs influenced how much value households were able to obtain from their systems.
Around one in four participating households moved onto a solar-specific tariff, while approximately half remained on a flat tariff.
Centre for Net Zero noted that remaining on a flat tariff removed the battery’s ability to respond to changing electricity prices throughout the day. The researchers also identified low consumer awareness as an important barrier.
For homeowners considering Solar PV, this is a useful reminder that maximising the benefits of a system can involve more than simply installing the equipment.
The way electricity is consumed, stored and purchased can all influence overall performance and financial savings.
Does This Mean Every Home Will Save 62%?
No, and this distinction is important.
The 62% figure is the result observed within this particular randomised controlled trial. It shouldn’t be interpreted as a guarantee that every UK property installing solar panels and a battery will reduce its electricity bill by exactly the same amount.
Real-world savings will vary considerably between properties.
Roof orientation and available roof space can affect solar generation, as can shading from trees or neighbouring buildings. The size and efficiency of the solar installation, battery capacity, household electricity consumption and the times at which electricity is used can all influence the outcome.
Electricity tariffs and export arrangements can make a difference too.
This is why a solar installation should ideally be designed around the individual property and household rather than using a one-size-fits-all approach.
Why Real-World Research Like This Matters
There are plenty of estimates available showing what solar panels could save a household.
What makes this research particularly interesting is the use of measured household energy data within a randomised controlled trial.
The researchers describe it as providing one of the only experimental estimates of the impact of residential solar and the first experimental estimate for solar combined with battery storage on energy demand and the grid.
That gives homeowners, installers and policymakers another useful source of evidence when assessing the role domestic renewable technologies could play in Britain’s future energy system.
It also demonstrates that the benefits can extend beyond generating renewable electricity.
How electricity is stored, when it is consumed and how much demand can be shifted away from peak periods are increasingly important considerations.
Solar and Battery Storage as Part of a More Energy-Efficient Home
Renewable generation can also form part of a wider approach to improving the energy performance of a property.
Reducing heat loss through measures such as insulation can lower the amount of energy a home requires in the first place, while renewable technologies can help supply some of the remaining energy demand.
Technologies such as an Air Source Heat Pump can also increasingly form part of this whole-house approach where appropriate.
The right combination of measures will depend on the property, its existing condition and the needs of the household.
What Can We Take From the Results?
The Centre for Net Zero trial provides compelling real-world evidence of the potential impact of combining residential solar PV with battery storage.
Across the 708 households studied, the researchers reported:
62% lower electricity bills, equivalent to around £681 per year; a 77% reduction in net electricity imports from the grid; a 66% reduction in grid imports during the 4pm–8pm peak; and an estimated £148 per year contribution to savings from the battery itself.
Individual results will always vary, but the research provides another valuable indication of the role solar generation and battery storage could play in reducing household electricity costs and changing how homes interact with the electricity grid.
At Render Right Renewables, we deliver energy-efficiency and renewable measures designed around the requirements of individual properties and projects. If you’re considering solar PV or other improvements to your property, our team can help you understand the options available.
Read the Centre for Net Zero study
