Solar Panel Calculator

Solar Panel Calculator: Estimating Costs and Savings Made Simple

When you first consider adding solar panels to your home, the amount of information to navigate can feel overwhelming. Questions like “How much will solar panels cost?” and “How much can I save?” often top the list of concerns. Answering these questions can be challenging, especially with a topic as technical as solar energy.

Understanding key factors like the number of solar panels needed, the space required for installation, and the energy output can seem daunting. That’s why Solartherm UK developed a user-friendly Solar Panel Calculator. With just a few inputs, this tool provides an instant estimate of solar panel costs and potential savings—helping you make informed decisions quickly and easily.

Why Use the Solar Panel Calculator?

Solar panels are a significant investment, and understanding the associated costs and benefits is crucial. As every home is unique, factors like size, roof design, and energy needs make estimating costs more complex. The Solar Panel Calculator simplifies this process by providing personalised insights, including:

What size solar panel system is right for you?

One of the main factors when considering solar panels is the size of the system. This will primarily be determined by the available space. Our solar panel calculator will show how much space will be required to install a given number of solar panels, making it easier to find out what is possible for you!

How do I calculate how many solar panels I need?

Knowing how many solar panels you need to power your home is a key consideration when thinking about investing in solar. But how do you figure that out? There are complex methods involved in calculating the generation from solar panels, as outlined by accrediting bodies such as MCS and EPVS. Our solar panel calculator does all this calculation behind the scenes, so all you need to know is how much electricity you use!

How much will it cost to install a solar panel system?

Our solar panel calculator will give a cost estimate for installing solar panels based on the configuration you choose. All you need to tell us is how many panels you need, your battery storage options and how much electricity you use!

What is the return on investment period for solar?

This is an important question when looking at solar options, and the return on investment (ROI) period will vary depending on the cost of the system and the amount of savings being made. Households with higher electricity usage have more potential for savings and will typically see a faster return, but our calculator will give an estimated ROI based on the information you provide.


How to use the Solar Calculator

Choose the number of Solar Panels

Solar Panel Calculator: Number of panels.

Select the number of solar panels. Unsure where to start? For reference, the average semi-detached house can fit 12-16 panels. The solar calculator will advise how much roof space you require.

You should base this selection on the section of your roof that is closest to south-facing.

Learn more about solar panel orientation…


Select your Battery Storage Option

Choose an option for battery storage.

Adding battery storage helps maximize the use of solar energy by reducing dependency on the grid. You’ll see how storage affects your savings.

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 the amount of electricity you use in a year.

This figure allows the calculator to estimate how much of the solar-generated electricity you will use, and therefore, how much you will save on your energy bill.

Your annual electricity usage will normally be shown on your electricity bill, and will be shown in Kilowatt Hours (kWh).

The Solar Panel Calculator is designed to make your solar journey as simple and stress-free as possible. From understanding costs and savings to planning your installation, we’re here to guide you every step of the way. Get started now!

Solar Panel Calculator: Costs and Savings Explained

Your Estimate

This is the estimated cost of the solar panel system based on the number of panels and the battery storage selection you have made.

The cost generated here is based on data for previous installations, but it is worth noting that every installation has different requirements, so costs can vary, both up and down. Different roof types, system configurations, and access requirements (eg. scaffolding) can alter the cost of an installation significantly. Find out more about solar panel installation costs…

To get a fully tailored cost and system design, contact us for a quote…

Your Bill Savings

The solar calculator will estimate how much you could save on your electricity bill based on the solar panel system configuration and your current annual electricity usage.

This is calculated based on how much electricity we would expect the selected solar panels to generate. This data is based on average data from the South-East UK (our main operating area). Actual efficiency will vary from one installation to another, due to orientation, shading and various other factors. Find out more about solar panel orientation and shading.

The bill savings calculation will also change based on battery selection. As a solar battery storage system allows you to use more of the energy you generate, the bill savings will typically increase with more battery storage. In reality, this will depend on your particular level and patterns of electricity usage. Find out more about solar panel battery storage…

To get a more accurate savings projection showing the total savings over the lifetime of the system, contact us for a custom quote…

Return On Investment

The return on investment represents the amount of time it would take for the savings to outweigh the cost of installation.

For most home solar panel systems, the return on investment period is between 5-10 years, but again, this will depend on all of the combined factors mentioned above.

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