As you may be aware, a 4kW Solar System is incredibly common since it is typically the right size to provide adequate power for the average-sized UK household of three to four persons.
On average, a 4kW solar set-up will consist of around 12 to 16 solar panels and is not only a way for homes to adopt renewable energy and play their part in the carbon-free future, but is also a way for households to massively reduce their energy costs and even make money by selling surplus power to the National Grid via the Smart Export Guarantee.
In the past one of the biggest limitations of solar has been their inability to produce and therefore provide energy outside of daylight hours.
However, thanks to the recent advancements in battery storage technology, this is no longer the case.
Solar systems with battery storage now enable UK households to benefit from the free energy of the sun 24 hours a day, providing a practical and reliable solution for the modern home.
Pro tip: Avoid upsells and confusing packages—choose a provider with a clear, fixed-price quote that won’t change. Heatable, a Which?-approved solar installer, offers transparent pricing with no surprises.
How Much Can You Save With a 4kw Solar System with Battery Storage?
The true figure will depend on a variety of factors, so an accurate figure is difficult to establish.
The following factors will determine how much energy your solar panels will generate:
- Your location in the UK will impact the annual sunlight hours you receive.
- Weather conditions.
- The position of your roof e.g. North vs South facing.
- The angle of your roof.
For example, if you have a north-facing roof, this will seriously limit the ability of your system. In such cases, you can consider installing a solar panel system on the ground or on the side of your property.
For a complete 4kw solar system installation you will need around 28 m2 of free roof space and the installation cost in total will be around £7,500.
Therefore, in the first year, you will be looking to make between £700-£800, so on average it will take around 10 years for you to break even.
That also means that you are looking to make a substantial profit over a 20-year period.
In fact, according to the Energy Saving Trust estimates an average household could make between £80 to £110 per month (based on an electricity unit price of £3.99 per kWh), which you can gain by selling surplus electricity via the Smart Export Guarantee scheme.
Smart Export Guarantee Scheme (SEG)
The Smart Export Guarantee scheme was introduced and launched on 1 January 2020 and is a government-backed initiative.
The SEG requires all UK energy suppliers to pay those who generate low-carbon electricity when they export it back to the national grid.
This of course includes the electricity generated from domestic solar panels.
This is how you will recover the costs of installing a solar panel system over time.
The actual government legislation means that all energy suppliers with over 150,000 customers need to offer at least one type of SEG tariff.
The average price of the tariff would be between 5-6p per kWh exported.
To be eligible, you need a small-scale low-carbon electricity generator, such as a 4kW solar system. Your solar installer must also be MCS-certified.
You can check the latest Smart Export Guarantee rates here.
Get a free estimate for your solar with the experts at Heatable:
- It’s free, easy, and without obligation
- Compare quotes & get the best prices
- Save up to £660 per year
Recommended reading:
The Feed-In Tariff (Defunct)
This Feed-In Tariff is no longer available and was replaced by the Smart Guarantee Export Scheme.
However, those who did apply and qualify for the scheme continue to benefit from it.
Benefits of Installing Solar Panels UK
Generating your own free power using the natural power of the sun is a great way to play your part in the UK’s renewable future since generating electricity via solar is emits zero carbon.
It’s not just about being green either, having solar panels means you are self-reliant and not at the mercy of the ever-increasing energy prices.
In fact, with solar, you can even make money from your energy supplier, what other energy system enables you to do that?
In a future of increasing use of electric vehicles, you could also potentially save thousands of pounds every year by charging your EV with the power generated from your solar PV set-up.
How Do You Know If A 4KW Solar System Is The Right Size For Your Home?
As mentioned a 4KW solar panel set-up will meet the power needs of the typical UK household and property, however, this of course is based on the average home.
If you think your energy demands are lower than average or higher e.g. you have a particularly large family, you will need to consider how this may impact the solar system size you need.
The first place to begin is with your annual electricity use.
This will identify how much energy you use and therefore how many panels you will need to generate that amount of energy year in and year out.
You can learn all about this in our guide on how to determine how many solar panels you will need.
Related solar guides:
- How many solar panels do you need?
- Smart Export Guarantee
- Can you install solar panels in a conservation area?
- Best 4kw solar system with battery storage
- Sunshine hours map UK
- Best Solar Panels
- Solar panel output calculator
Get Quotes on 4kW Solar Panel Systems
The best next step is to get assistance from a solar installation expert, who be able to walk you through the entire process and provide you with an accurate quote based on your specific circumstances.
We recommend seeking at least three estimates from different solar companies to get a good idea of how much you can expect to pay.