What’s the Total Cost of Solar Panels and Battery Storage in the UK?

The total cost of a solar system in the UK varies depending on the home size, energy use, the equipment, and other factors. In 2025, UK households can typically expect to pay between £13,000 and £18,500 for a complete solar panel and battery storage system. While prices vary, the long-term savings and energy independence make this a popular upgrade for many homeowners. In this article, we’ll break down the typical costs of panels and batteries, what affects the price, and how to estimate what your system might cost.

In 2025, a solar array typically costs between £5,000 and £13,500 in the UK, and solar batteries will cost anywhere between £2,000 and £12,000. 

When you buy them together, you often save on installation. The average solar panel and battery storage system for a 3-bedroom house is between £13,000 and £18,500. Your price could be about half that for a small flat with low energy needs.

The cost of the system depends primarily on its size. You can estimate the price from your electricity bills’ kWh usage to understand what it might cost you. Your location, roof orientation, complexity of the installation, and the type of products you buy will also affect your final price.

The most common solar array for a three-bedroom house in the UK is a 3.5kW system, which generally requires 9 to 10 solar panels.

You can estimate the number of panels you need based on your daily average energy use in kWh, where:

Number of panels = Daily energy usage (kWh) ÷ Solar panel output (kW) x 4 (UK peak sunlight hours) x 0.75

Let’s say you use 10kWh daily and you’re purchasing 400W panels (=0.4kW), then:

10kWh ÷ (0.4kW x 4 x 0.75) = 8.33

This means that you would need nine 400W panels to meet your needs.

• Energy Consumption: The most significant factor is how much energy you consume. Those with higher energy needs require more panels.
• System Size: Larger homes with larger roofs also require more panels, which increases the cost.
• Type of Solar Panels: Monocrystalline solar panels are far more efficient and durable, but they cost a bit more, around £1 per watt. Polycrystalline solar panels cost about £0.90 per watt. However, those small savings will cost more in the long run since polycrystalline panels are less efficient, requiring more panels to generate the same amount of electricity.
• Roof Orientation: South-facing roofs produce the most energy, while east and west-facing roofs produce less and require more panels. North-facing roofs have the lowest output in the UK, requiring more panels and more complex installations.
• Complexity of Installation: Older buildings, larger buildings, double-storey homes, and houses with uniquely shaped roofs will also require more complex installations, increasing installation fees.
• Local Factors: Shade from nearby buildings or trees also requires more complex installations and may require additional panels. Homes with a clear, unrestricted view of the sky are the easiest and cheapest to install.
• Location: The UK gets four peak sunlight hours on average, but some locations may only get 2 to 3 hours and will require more panels to meet their needs.
• Government Incentives: Your system's cost could be significantly lower if you’re eligible for rebates, grants, or tax credits.

Just like with solar panels, the size of your domestic battery storage will depend entirely on your energy needs. It also depends on the size of your solar array and how much of your solar output you want to save for later use. 

It’s important to size your solar battery storage to match your array and energy needs, so there’s no one-size-fits-all answer. However, let’s look at some averages. 

• A 1 or 2-bedroom home with a 2.1kWp array with 6 panels will need about 4kWh of storage, costing around £4,000.
• A 3-bedroom home with a 3.5kWp array with 10 panels will need about 5 kWh of storage, which costs about £5,000.
• A large 4+ bedroom home with a 4.9 kWp array with 14 panels will need about 10kWh of storage, costing an average of £9,000.

• Inverters: AC-coupled battery storage systems require an inverter since batteries store electricity as DC (direct current), but homes typically need AC (alternating current). Quality battery systems already have built-in inverters perfectly sized for their capacity, reducing purchase and installation costs compared to buying them separately. 
• Battery Type: Lead-acid batteries are a bit cheaper, but they will cost you much more in the long run since you will likely have to replace them 2-4 times before you replace a LiFePO4 battery just once. 
• Charging Cycles: This refers to how often a battery can be fully discharged and charged before it starts declining noticeably in capacity. Lead-acid batteries may only have 300-500 charging cycles, while the LiFePO4 batteries in the EcoFlow Power Ocean (Single-Phase) have 6000 or more.
• Depth of Discharge (DoD): This refers to usable battery capacity. Lead-acid models typically only have a DoD of 50%, meaning only half of their capacity is usable, requiring more batteries to meet your needs. The LiFePO4 models in EcoFlow products have a DoD of 100%. 
• Warranty: Solar batteries may come with warranties between 5 and 15 years. The better the warranty, the better the product, and the more likely it will last longer, which means it may cost more. 

• Smart Features: The best solar batteries have advanced battery management systems (BMS) to optimise their charging and discharging, prolonging their lifespan. They may also have energy management systems (EMS) where you can control them and track their performance via a mobile app. Another feature of premium batteries is the ability to instantly operate as an emergency power source during a power cut without feeding any energy back to the grid, which poses a safety risk for workers. 
• Installation Costs: Professional installers must install your system to hook it up to your household electrical and the grid. More complex systems cost more to install. However, if you get panels and batteries done at the same time, you generally save on installation costs compared to doing them separately. 
• Three-Phase Systems: Installing a three-phase system will increase your costs because you will need to bring a special three-phase power supply to your home. If you have a three-phase system, you should get a battery designed for it, like the EcoFlow Power Ocean (Three-Phase). 
• Government Incentives: Finally, several grants and rebates are available for UK homeowners and businesses looking to install home battery storage systems, which could significantly reduce the upfront cost.

The cost of installing solar panels and batteries in the UK varies considerably depending on the size of the home and other factors. However, the average 3-bedroom home will cost between £13,000 and £18,500. Smaller homes would pay less, and larger homes would cost more.

Assuming you use renewable energy rather than grid power for charging, there aren’t hidden costs beyond the initial installation. However, if you have a contract, service costs may be associated with it. There’s also the eventual replacement and disposal, but quality batteries should last at least 15 years.

Solar batteries allow you to store excess energy you produce during the day so you can use it at night, saving significant money and reducing your carbon footprint. Even if you sell excess solar energy back to the grid, you get paid far less than what you pay for grid power.

The total cost of installing solar panels and battery storage in the UK varies with energy needs, system size, battery type, and installation complexity. Still, the long-term savings and greater energy independence outweigh the upfront investment for many. Smart systems like the EcoFlow Power Ocean (Single-Phase) help simplify installation while delivering reliable performance, high efficiency, and long lifespans. With electricity prices rising, now is an excellent time to invest in a system tailored to your household needs.