Real World Solar & Battery Case Study: 9.58 MWh Generated in the First Year

How a larger solar array, battery storage and smart energy tariffs are helping power an all-electric Staffordshire home

When considering solar panels and battery storage, one of the biggest questions homeowners ask us is simple:

"What will it actually save me?"

Solar proposals normally rely on estimated generation, predicted electricity usage and assumptions about future energy prices. While these calculations are useful, there is nothing quite as valuable as looking at real world results from an installed system over a complete 12 month period.

One of our customers in Balterley, Staffordshire recently shared the first full year of performance data from the solar PV and battery storage system installed by Underwood Electrical.

The results cover 1 August 2025 to 31 July 2026, giving us a complete year including the lowest generation winter months and the peak spring and summer period.

And the results are impressive.

Solar PV installed at the customer's Staffordshire property

The headline results

During its first full year, the system generated:

9,581.15 kWh - or 9.58 MWh - of solar electricity.

Before moving to an all electric home, the customer's household energy costs were approximately:

• • Electricity: £173 per month / £2,076 per year
• • Gas: £120 per month / £1,440 per year
• • Combined energy cost: £293 per month / £3,516 per year

The property is now fully electric, including its heating.

Although Underwood Electrical did not install the heat pump, the solar PV and battery system now forms a major part of the home's overall energy strategy, helping provide electricity for normal household consumption as well as the additional electrical demand associated with heating.

Using a combination of solar generation, battery storage, intelligent import/export tariffs and energy flexibility, the customer reports that their overall household energy account for the first year is approximately net zero cost or better - even after taking the electricity standing charge into account.

They have also received an additional £148 through Axle Energy for participating in qualifying battery flexibility events.

Actual solar generation - month by month

One of the most useful parts of having a complete year's data is seeing just how much solar generation varies throughout the seasons.

The customer's actual measured generation was:

Month	Solar Generation (kWh)
August 2025	1,170.00
September 2025	802.05
October 2025	371.83
November 2025	230.98
December 2025	145.16
January 2026	170.58
February 2026	271.26
March 2026	699.29
April 2026	1,220.00
May 2026	1,420.00
June 2026	1,430.00
July 2026	1,650.00
Total	9,581.15

This demonstrates something we regularly explain when designing solar installations.

Solar isn't about expecting the same production every month.

December produced around 145 kWh, while July produced 1,650 kWh - more than eleven times as much.

A properly designed system therefore needs to be considered across the whole year, alongside the property's electricity consumption, battery capacity, available tariffs and export opportunities.

Why installing a larger solar array can make sense

One of the interesting conclusions from this installation is the benefit of making sensible use of the available roof space.

There is sometimes a temptation to size a solar installation purely around a property's current daytime electricity consumption.

However, modern energy systems can work very differently.

Surplus solar electricity doesn't necessarily have to be wasted.

Depending on the installation and tariff, surplus generation can be used to:

• Charge a home battery for use later in the day.
• Reduce electricity imported from the grid.
• Help supply high demand electrical loads.
• Support an all electric home and heat pump.
• Charge an electric vehicle.
• Export electricity back to the grid for payment.

This particular system demonstrates the amount of energy that can become available from a larger array during spring and summer.

In just four months it generated:

• April - 1.22 MWh
• May - 1.42 MWh
• June - 1.43 MWh
• July - 1.65 MWh

That's approximately 5.72 MWh of solar generation in four months alone.

A larger solar array makes productive use of the available roof space.

Battery storage changes how solar can be used

Solar generation is only part of the story.

Adding battery storage allows electricity to be moved from the time it is generated to the time it is actually required.

Rather than relying solely on solar electricity while the sun is shining, surplus generation can be stored and used later.

Modern battery systems can also potentially take advantage of off peak electricity tariffs, allowing batteries to charge from the grid when electricity is cheaper and supply the property during more expensive periods.

Depending on the battery, tariff and service provider, batteries can also participate in flexibility or Virtual Power Plant services.

In this case, the customer earned an additional £148 through Axle Energy, alongside the wider savings and export benefits achieved by the system.

From £3,516 a year in household energy costs to approximately net-zero

Perhaps the most striking part of this case study isn't simply how much solar electricity was generated.

It is what has happened to the customer's overall household energy costs.

Previously, they were spending approximately:

£3,516 per year on gas and electricity.

The property has subsequently become an all electric home.

The customer still pays an electricity standing charge of approximately 68p per day, equivalent to around £248 per year, regardless of how much electricity is consumed.

However, after considering their solar generation, battery management, electricity imports and exports, the customer reports that their overall annual household energy position is approximately break even or better, including the standing charge.

This is an important distinction.

It doesn't mean the house never imports electricity from the grid.

Instead, electricity can be imported when required - potentially at cheaper times - while surplus solar generation can be exported at other times. Battery storage provides another layer of flexibility between the two.

It is the overall annual financial position that matters.

What about the payback?

The original investment in the solar and battery system was £12,400.

Using the customer's previous annual gas and electricity expenditure of £3,516, together with the additional £148 received through Axle Energy, the customer's own simple calculation gives an indicative annual financial benefit of at least £3,664.

That produces a simple indicative payback calculation of:

£12,400 ÷ £3,664 = approximately 3.4 years.

There are, however, some important qualifications.

This is a real customer's individual first year result, not a guaranteed payback period for every solar installation.

The property has also transitioned from gas to an all electric heating system. Underwood Electrical installed the solar and battery system but did not install the heat pump, so it would be incorrect to suggest that solar panels alone eliminated the previous gas bill.

The customer's overall financial result reflects the interaction between the property's solar generation, battery storage, electricity consumption, heating demand, import and export tariffs and flexibility payments.

Energy prices, weather, household consumption and tariffs can all change, so future performance and savings will vary.

What did the customer think?

After completing the first full year with the system, the customer told us:

"The system has exceeded my expectations."

They also explained that the most important result wasn't simply generating 9,581 kWh of electricity.

It was having sufficient solar generation, combined with battery storage and intelligent use of import and export tariffs, to support an all electric home whose previous gas and electricity bills totalled approximately £3,516 per year.

For this customer, the experience has reinforced the benefits of making proper use of the available roof space rather than automatically installing the smallest possible solar array.

Our approach to solar and battery design

At Underwood Electrical, we don't believe solar PV should simply be a case of fitting a predetermined number of panels to every property.

Every home is different.

When designing a solar and battery system, we can consider factors including:

• Current and future electricity consumption.
• Available roof space and orientation.
• Shading.
• Battery storage requirements.
• Electric vehicles.
• Heat pumps and future electrification.
• Import and export tariffs.
• DNO/grid connection requirements.
• The potential value of additional generation and export.

Where the property, budget and grid connection allow, making sensible use of the available roof space can provide significantly more generation and greater flexibility for future energy requirements.

This first year case study is an excellent real world example of what that approach can achieve.

Considering solar panels or battery storage?

If you're considering solar PV, home battery storage or upgrading an existing renewable energy system, Underwood Electrical can design a system around your property and actual energy requirements.

We install and support solar and battery systems across Staffordshire, Cheshire and Shropshire, including Newcastle-under-Lyme, Stoke-on-Trent, Crewe and surrounding areas.

From initial design and DNO applications through to installation, commissioning and certification, we can provide a complete renewable energy solution.

Contact Underwood Electrical to discuss your property and find out what solar and battery storage could achieve for your home.

Case study based on actual customer supplied data for the period 1 August 2025 to 31 July 2026. Individual savings and financial returns vary according to system design, energy consumption, weather, electricity tariffs, export rates and future energy prices. Figures should not be interpreted as a guaranteed level of performance or financial return.

Contact Underwood Electrical to arrange a renewable energy survey and find out what greater control over your home's energy could look like.

Get in touch Call 01782 703255