The Energy Saving Trust recommend that you receive at least
three quotes from approved local Solar PV installers.

Get 3 Free Surveys & Quotes from Approved Installers..
A domestic Solar PV system typically costs between £3,000 to £6,000 depending on system size.
There are NO up-front grants and NO free systems available. FITs cover the cost.

I understand there are NO up-front grants and       NO free systems available.

An Energy Advisor will call you back during office hours to check your roof and organise your quotes.

Solar PV Feed In Tariff Calculator

To use our Solar PV Feed in Tariff Calculator, simply change the values in the left column, and click the Calculate button. Some common values have already been selected for you. Please see the information below the calculator for an explanation of how it works.

Enter Solar PV System Details:
Most systems are building tied. Standalone systems are not attached to a property and only feed electricity into the grid. 

Please enter the system size you require. 

Please select how much electricity you will export based on how much time you spend in the property. 50% is the most common. 

Please select the approximate region you live in as per the map below. 

Solar PV Feed in Tariffs Calculator
Estimated Costs and Savings:
Please amend the details on the left to generate your estimated costs and savings.

Estimated System Cost (£) 0

Annual Estimates..

Electricity Generated (kWh) 0

Generation Tariff Income (£) 0

Export Tariff Income (£) 0

Electricity Bill Savings (£) 0

Total Income & Savings (£) 0

20yr Income & Savings (£) 0

Payback Time (yrs) 0

Return On Investment (%) 0

Panel Space Required (sq. metres) 0

Important Note:
These figures are estimates based on the assumptions listed below. Surveyors will provide exact costs and more accurate income and saving projections.


The Energy Saving Trust recommend that you receive at least
three quotes from approved local Solar PV installers.

Click Here To Get 3 Quotes

Calculator Inputs:

System Type
The vast majority of Solar PV systems are connected to a building i.e. Building-Tied. Higher Feed in Tariff rates are paid for Building-Tied systems.

System Size
The bigger the system, the more money you can make from Feed in Tariffs. However, the size will depend on your budget and the available roof space. Our calculator works with all values from 1kWp to 250kWp but bear in mind that different rates are paid depending on the size of the system:

System Size * Generation Tariff Level (p/kWh)
  Systems installed from 1st April 2014
Up to 4 kWp 14.38
Over 4 kWp up to 10 kWp 13.03
Over 10kWp up to 50kWp
Over 50kWp up to 100kWp
Over 100kWp up to 150kWp
Over 150kWp up to 250kWp
Over 250kWp
Standalone** 6.61
* Prices shown are in pence per kilowatt hour (p/kWh).
** Standalone systems are not connected to a building.

It is common for installations to come close to but not more than the upper limits to take advantage of the higher rates. If you are not sure how much space is available on your roof, each kWp takes up roughly 8m2 which is about the size of two family saloon cars. Some example installations are shown in the images below:

Solar System Size 1.4kWhSolar System Size 2.2kWh

Solar System Size 2.9kWh Solar System Size 3.8kWh

Based on the system size entered, the calculator will estimate the space required to locate the solar panels.

Estimated Export
The Export Tariff is paid together with the Generation Tariff by the Utility company of your choice. It does not have to be whoever supplies your electricity. Most Utility Companies will assume a 50% export and do not measure the actual amount fed back into the grid. If you think you will export all of the electricity (i.e. not use any) choose 100% Exported. Similarly, if you think you will use all of the electricity choose 0% Exported. The latter is the best option because by using the electricity you save around 14p per kWh by not purchasing it from your supplier. Exporting electricity only pays 4.77p per kWh.

Choose the region you live in based upon the map. The further North you live, the lower the levels of Solar Irradiation. There are less hours of sunlight and generally poorer conditions the further North you are. However, location is not a major factor because Feed in Tariffs still produce a good return on investment no matter where you live. If you are in an area that appears to border two regions, select one region at a time and see how much difference it makes. This does not make any difference to applying for quotes through our web site and our installers will be able to estimate the amount of electricity produced more accurately.

The Energy Saving Trust recommend that you receive at least
three quotes from approved local Solar PV installers.

Click Here To Get 3 Quotes

Calculator Outputs
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Estimated System Cost
This is an estimated maximum figure based upon the national average installation cost. In many cases, the cost will be lower and so the payback time and the return on investment will be better. A surveyor can give you actual costs and estimate the savings more accurately.

Electricity Generated
A 2.5kWp system can produce 2171 kWh of electricity per year. Other factors affecting the amount of electricity generated are the region you live in (as explained above). The direction and tilt of the panels can also affect output, as explained in the assumptions section below.

Generation Tariff Income
This amount is paid for every kWh of electricity produced. The table underneath the calculator shows the rates paid depending on system size.

Export Tariff Income
The export tariff is 4.77p per kWh. As explained above, most Utility companies assume 50% of the electricity generated is exported. As above, the more electricity you use from Solar PV the better because you are not having to buy it from the grid at around 14p per kWh.

Electricity Bill Savings
This value depends on how much electricity you use and how much is exported. If you don't use any of the electricity, this figure will be zero. If you use it all, you will save 14p per kWh as you're not having to buy electricity from the grid.

Total Income & Savings
The total of the Generation Tariff, Export Tariff and Savings made on electricity bills over a period of one year.

Lifetime Savings
The Total Income & Savings per year multiplied by the Feed in Tariff period of 20 years. After this time you will continue to save on bills if you use the electricity produced.

Payback Time
This is an approximation of the length of time it will take to recover the initial cost of the system.

Return On Investment
This is the annual return on investment, calculated as a percentage of the initial installation cost.

Panel Space Required
An estimate of the amount of space you will need to install the panels for the size of system required. As mentioned above, each kWp requires approximately 8m2 of space.

The Energy Saving Trust recommend that you receive at least
three quotes from approved local Solar PV installers.

Click Here To Get 3 Quotes

Calculator Assumptions
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An average electricity price of 14.4p per kWh is assumed. If you pay less for your electricity you will not save as much money by using the electricity generated. Conversely, if you pay more than this you will save more. The calculator also assumes that the roof faces due South and the panels are angled at 30 degrees which is the position in which they will generate the most electricity. The table below shows the percentage decrease in performance when the optimal direction and tilt are not achieved.

Tilt South SE / SW E / W
10 Degrees 96% 94% 89%
20 Degrees 98% 96% 87%
30 Degrees 100% 96% 85%
45 Degrees 98% 93% 80%
60 Degrees 92% 86% 72%
Most roofs in the UK are angled at between 30 and 45 degrees.

Providing there is some tilt and the panels face somewhere between East and West (through South), you will still achieve a good return on investment that will make the installation of Solar PV panels worthwhile. If you are unsure of the available space, the direction the roof faces or whether it is shaded then use our Roof Checker.

Solar Panels will perform best on roofs that face somewhere between South East and South West via South. Panels on a roof that is directly South-facing will generate the most electricity.

EnergyLink’s Solar Installers can also fit Solar Panels onto East and West facing roofs. In these circumstances, the panels are often installed on both faces for maximum benefit and without significant reduction in the amount of electricity generated.

Other directions – including North West, North and North East – are not suitable for Solar Panels.

Solar PV Calculator Assumptions
> An average electricity price of 14.4 pence per. kWh.
> The panels face in the optimal direction i.e. South facing.
> The angle or tilt of the panels is optimal for your location.
> No shading by trees, buildings, etc. as this reduces performance.
> Does not include maintenance costs but they are typically low.
> Does not account for variations in electricity prices.
> Does not account for inflation but FITs are index linked.
> Space required for panels assumes 8m2 per kWp.

Your property must have an Energy Performance Certificate (EPC) rating of
D or above to receive the Feed in Tariff rates quoted above. Read more.
Roof Checker

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