How Much Do 3kW Solar Panel Systems Cost?

A 3kW solar systems can cost as little as £3,950 and you can expect to earn up to £10,240 over 20 years.

However the government plan to cut solar panel earnings in 2016 so you can need to install this year to lock in your guaranteed earnings over the next 20 years.

Fill in the form at the top of the page to compare the prices of local solar installers.

3kW Solar Panel Systems

3kW solar panel systems are a popular residential solar panel option for many households in the UK. However, if you have enough space on your roof, you will earn more by installing a 4kW system.

A 3kW system requires approximately 21 square meters amount of shade free roof space whereas a 4kW systems requires 28 square meters of roof space.

A 3kW is still a popular option and will deliver a healthy return on investment.

Important news update

The government is planning to cut the amount solar systems can earn from the Feed-in Tariff by 87% in January 2016.

The Feed-in Tariff pays you for producing renewable energy and is what makes installing solar panels profitable.

If you are considering installing solar panels, you will earn far more by installing in 2015 as you will lock in the current high Feed-in Tariff rate for 20 years.

Click here to learn more

How much does a 3kW system cost?

Prices of 3kW systems have fallen by over 70% in recent years. The table below compares the price of a 3kW solar panels to other similar sized systems.

Typical System Size

Approximate Roof Space

Estimated Cost (£)

Estimated Annual Output

Profit Over 20 years

8 sq m
14 sq m
21 sq m
28 sq m

You can compare prices of 3kW systems from your local installers by clicking here

How much will I make by installing a 3kW system?

As we mentioned above, the amount the Feed-in Tariff pays out will be slashed by 87% in January 2016.

If you install this year you will be unaffected by the cut as once you install you get locked in.

The table below shows how much a typical 3kW system will earn you if you install in 2015.

Typical System Size

Return per Year

Return over 20 years

Profit over 20 years


If you install in 2016 or later you can expect to earn much less from solar panels, including 3kW systems. If you are considering solar panels you will earn much more by installing this year before the Feed-in Tariff gets cut in 2016.

Is a 3kW solar panel system right for me?

While a 3kW system installed before January 2016 will generate a high return on investment, a 4kW system will deliver an even higher amount of earnings. So if you have adequate roof space you will want to also consider a bigger sized panel than a 3kW.

It’s always best to speak to installers you receive quotes from about this; they will be the best people to advise on your situation and property.

Cheap 3kW Systems

Be careful when choosing a solar panel based on price alone. Often more expensive makes and models outperform the cheaper options. The greater the power output the greater the return from the feed in tariff scheme, so the best value option may be the more expensive one. Check the specifications of each model to calculate your potential return.

You can join the thousands of homeowners who use The Eco Experts to compare prices of local solar installers. This is a a free comparison tool with no obligation.

Compare solar prices in your area

Back to top