Solar Panel Calculator: Estimate Costs & Savings with Ease

When you first start exploring solar panels for your home, the amount of information available can feel overwhelming. One of the first questions most homeowners ask is: “How much will solar panels cost?” closely followed by “How much could I save on my energy bills?”

Understanding factors such as system size, roof space, energy generation, and potential return on investment can quickly become confusing. That’s why at SolarTherm UK we developed a simple, easy-to-use Solar Panel Calculator.

By entering a few basic details, our calculator provides an instant estimate of:

Solar panel installation costs
Potential energy bill savings
Estimated return on investment
Recommended system size
Battery storage options

Our Solar Panel Calculator helps you understand the potential benefits of solar energy in minutes, making it easier to plan your switch to renewable energy with confidence.

Use the Solar Panel Calculator

Our easy-to-use Solar Panel Calculator helps you explore the potential costs, savings, and benefits of switching to solar energy for your home.

With just a few simple details, you can:

Get an instant estimate for a solar panel system, with or without battery storage
See how much you could save on your energy bills
Compare costs and savings across different solar panel system configurations
Discover how much roof space may be required for your installation
Explore finance options for solar panels and battery storage
Save your estimate by email to review later or request a full system design and quotation

The calculator is designed to give you a quick, straightforward overview of what solar could look like for your property—helping you make informed decisions with confidence.

Get Started…

Why Use the Solar Panel Calculator?

Installing solar panels is a significant investment, so understanding the potential costs, savings, and long-term benefits is essential. Since every property is different, factors such as roof size, layout, energy usage, and battery storage requirements can all affect the final system design and cost.

That’s why the SolarTherm UK Solar Panel Calculator is designed to simplify the process by providing personalised estimates based on your home and electricity usage.

What Size Solar Panel System Is Right for You?

One of the most important considerations when exploring solar energy is choosing the right system size. This is often determined by the available roof space and your household’s electricity consumption.

Our Solar Panel Calculator helps you understand:

How many solar panels may fit on your roof
The estimated roof space required
The potential energy generation of different system sizes

This makes it easier to see what may be achievable for your property before requesting a full survey.

How Do I Calculate How Many Solar Panels I Need?

Calculating how many solar panels are required to power your home can be complicated. Accurate estimates depend on several technical factors, including roof orientation, shading, panel efficiency, and annual electricity consumption.

Industry-standard calculations used by organisations such as MCS and EPVS can be complex, but our calculator handles these calculations automatically behind the scenes.

All you need to do is enter a few simple details, including your electricity usage, and the calculator will estimate the recommended system size for your home.

How Much Does It Cost to Install Solar Panels?

The cost of a solar panel installation depends on several factors, including:

System size
Number of solar panels
Battery storage options
Installation complexity
Energy requirements

Our Solar Panel Calculator provides an estimated installation cost based on the configuration you choose, helping you understand potential investment levels before speaking with our team.

What Is the Return on Investment for Solar Panels?

Understanding the potential return on investment (ROI) is a key part of deciding whether solar panels are right for your home.

The payback period will vary depending on:

The overall system cost
Your electricity usage
Energy prices
Whether battery storage is included
How much electricity you use during the day

Homes with higher electricity consumption often benefit from greater savings and faster payback periods. Our calculator provides an estimated ROI based on the information you enter, helping you better understand the long-term value of investing in solar energy.

How to use the Solar Calculator

Choose the number of Solar Panels

Solar Panel Calculator: Number of panels.

Select the number of solar panels you would like included in your estimate. Unsure where to start? As a guide, the average semi-detached home in the UK can typically fit between 12 and 16 solar panels, depending on the available roof space.

The Solar Panel Calculator will estimate how much roof space is required for your selected system size, helping you understand what may be suitable for your property.

For the most accurate results, base your selection on the section of your roof that is closest to south-facing, as this generally provides the best solar energy generation.

Learn more about solar panel orientation…

Select your Battery Storage Option

Choose a battery storage option for your solar panel system.

Adding battery storage allows you to store excess solar energy generated during the day for use later, helping to reduce your reliance on the electricity grid and maximise your energy savings.

The Solar Panel Calculator will show how different battery storage options can affect your estimated savings, energy usage, and return on investment.

Learn more about solar panel battery storage…

Solar Panel Calculator: Battery Storage selector

Enter your annual Electricity Usage

Solar Panel Calculator: Annual Energy Usage.

Enter your estimated annual electricity usage.

This information helps the Solar Panel Calculator estimate how much of the electricity generated by your solar panels you are likely to use within your home, which in turn allows it to calculate your potential energy bill savings more accurately.

You can usually find your annual electricity consumption on your electricity bill or annual statement, displayed in kilowatt hours (kWh).

The SolarTherm UK Solar Panel Calculator is designed to make your switch to solar energy as simple and stress-free as possible.

From estimating installation costs and potential savings to understanding system size, battery storage, and return on investment, our calculator helps you explore your options with confidence.

Whether you are just starting your solar journey or ready to request a tailored quotation, we’re here to guide you every step of the way.

Get started today and discover how much you could save with solar.

Launch the Solar Panel Calculator

Solar Panel Calculator: Costs and Savings Explained

Your Estimate

This is the estimated cost of your solar panel system based on the number of solar panels and battery storage option you have selected.

The estimate is generated using data from previous installations completed by SolarTherm UK. However, every property is different, so actual installation costs can vary depending on factors such as:

Roof type and layout
System size and configuration
Battery storage requirements
Cable routes and electrical works
Access requirements, including scaffolding

Because of this, installation costs may vary both above and below the estimate shown by the calculator.

To receive a fully tailored system design and accurate quotation for your property, please contact us for a personalised quote.

Your Bill Savings

The Solar Panel Calculator estimates how much you could save on your electricity bills based on your selected solar panel configuration and annual electricity usage.

These estimates are calculated using expected solar energy generation data for the South East of the UK, which is our primary operating area. Actual system performance may vary depending on factors including:

Roof orientation
Shading
Panel positioning
Local weather conditions
Your household’s electricity usage patterns

Battery storage selection can also significantly affect your projected savings. Adding a solar battery allows you to store and use more of the electricity your system generates, reducing the amount of energy you need to import from the grid.

In many cases, increased battery storage can improve overall energy bill savings, although this will depend on your individual energy usage habits.

For a more detailed savings forecast, including projected lifetime savings and performance estimates, contact us for a custom solar quotation.

Return on Investment

The return on investment (ROI) estimate shows approximately how long it may take for your energy bill savings to offset the cost of installing your solar panel system.

For most residential solar panel systems in the UK, the estimated payback period is typically between 5 and 10 years. However, this can vary depending on several factors, including: