• Save 70% On Average On Your Electricity Bills
  • Accredited Installation Teams
  • Expert Advisors Ready To Help You

Solar Panel Calculator

Our easy-to-use solar power calculator can help you estimate the potential benefits of installing a solar photovoltaic (PV) system. It’ll take into account your location, energy usage, and other factors to provide you with an estimate of your fuel bill savings and potential payments.

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How much could you save?

  • Save 70% on average on your electricity bills
  • Expert advisors with decades of experience
  • Partner with Growatt, the No. 1 global supplier
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How to Use the Calculator

To use the solar panels cost calculator, you’ll need to provide some basic information about your home, including your roof size, the direction your roof faces, and your average energy usage. You’ll also need to select your location and the type of solar panels you’re interested in.

Once you’ve entered your information, the calculator will generate an estimate of your potential benefits. The estimate will include the following information:

  • The amount of electricity your solar system could generate each year
  • The amount of your fuel bill that could be saved each year
  • The potential energy grants or funding payments you could be eligible for

Start using the calculator using the form below! Find out how Grant Store can help you secure free solar energy.

How much could you save?

  • Save 70% on average on your electricity bills
  • Expert advisors with decades of experience
  • Partner with Growatt, the No. 1 global supplier

Our Accreditations & Brands We Work With

  • jinko-solar-logo
  • huawei-logo
  • giv-energy-logo
  • growatt-logo
  • fox-ess-logo
  • viridian-solar-logo
  • esdec-logo
  • solar-edge-logo
  • solis-inverters
  • niceic logo
  • schletter-logo
  • MCS-logo
  • lg-logo
  • Tesla Energy
  • Construction Line
  • JA Solar
  • Gas Safe Register

Frequently Asked Questions

How do I calculate how many solar panels I need?

The number of solar panels you need depends on your annual energy usage, the efficiency of the solar panels you want to use, the amount of daylight you get, and the area of your roof.

Just use the solar calculator or speak to one of our solar installation experts instead; it’s far easier!

How much electricity do you get from one solar panel?

The amount of electricity you get from a solar panel depends on a number of factors, including the efficiency of the panel, the amount of daylight it receives, and the temperature. In general, a typical solar panel can produce between 250 and 400 watts of electricity per hour in full daylight. This means that a single solar panel could generate between 0.5 and 0.8 kWh of electricity per day.

How many solar panels are needed for 1 kW?

Three panels should be enough to generate this amount of electricity.

How much power does a 4 kW solar system produce per day?

Taking the various factors mentioned above into consideration, a 4 kW system would typically produce between 16 and 24 kWh of electricity per day in optimal conditions (based on between 6 and 10 hours of daylight ).

Grant Store – so much more than by the numbers

We’ve already helped thousands of homes, businesses, and local authorities install energy-saving solutions that have been life-changing both in terms of helping the environment and drastically lowering their energy costs.

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