Solar Panels and Battery Cost in the UK

A battery can help you make the most of the electricity you generate from your solar panels.

Adding a battery to your solar system allows you to store unused solar energy during the day and use it at night when the panels aren’t generating electricity.

Data from the Energy Savings Trust shows you can save around 14p for every unit of electricity you store in a battery and use at night.

But how much do you need to invest in a solar panel battery, and what should you consider?

Here’s everything you need to know about solar panel battery costs in the UK.

Quick Takeaways:

  • Solar panel battery costs can range from £2,000 to £6,000.
  • Factors impacting solar panel battery costs include the type, capacity, lifespan, and installation costs.
  • A battery can help you live a greener lifespan and reduce your energy bills by allowing you to use more of the low-carbon energy you generate.

How Much Does a Solar Panel Battery Cost?

A new solar panel battery can cost between £ 2,000 and £6,000. Costs can vary widely due to factors like size, warranty, brand, and type of battery.

The Energy Savings Trust shows that prices can reach up to £8,000, but prices are expected to decrease as batteries become more popular, and the technology continues to evolve and improve.

What Factors Influence Solar Panel Battery Costs?

Factors that influence how much you pay for a solar panel battery include:

Battery Type

The types of battery you choose will play a significant role in the overall cost. The two main types of solar panel batteries include:

  • Lead Acid Solar Batteries

Lead-acid batteries have been around for centuries and are one of the cheapest options available.

On average, a 4kWh lead-acid solar battery costs around £2,000 and offers 1,800 lifecycles, translating to around five years when used daily.

They’re a reliable option for solar energy storage but are now considered outdated and inefficient compared to more modern options.

They have a shorter lifespan and a significantly lower depth of discharge (DoD), which is how much you can use the battery before recharging it.

  • Lithium-ion Solar Batteries

Lithium-ion batteries are more expensive but still enjoy a more significant market share in residential solar panel systems.

A 4kWh lithium-ion solar battery can cost around £4,000 on average, double that of a similar lead-acid battery.

However, they’re more cost-effective thanks to their longer lifespan and better performance.

For example, a 4kWh lithium-ion battery can feature around 4,000 lifecycles and a DoD of up to 90%. They’re also more compact and lightweight, with higher storage capacities and faster charging speeds.

Related reading:

Battery Capacity

The capacity of a battery refers to how much energy it can store. It’s measured in kilowatt-hours (kWh) and directly influences the cost of the solar battery.

Generally, the more storage capacity a solar battery offers, the more expensive it will be since it can store more energy.

Various factors will impact the battery size you’ll require, including your property’s size, energy usage, and how much your solar panels can generate.

There’s no point in buying a battery that’s bigger than what your solar panels can fill or one that’s too small for your evening and night-time electricity use.

The table below shows examples of appropriate battery sizes based on house size and solar panel power output:

House SizePower Output (kWp)Solar Battery Size
1-2 bedrooms2.1 kWp (6 panels)4 kWh
3 bedrooms3.5 kWp (10 panels)5 kWh
4+ bedrooms4.9 kWp (14 panels)10 kWh

Battery Lifespan

The lifespan of a battery refers to how long it will last before you need to replace it. One essential indicator of a solar battery’s lifespan is its lifecycle.

Batteries with a more significant number of cycles have a longer lifespan and will generally cost more upfront, but they can be more cost-effective long-term since they don’t require frequent replacement.

The battery cycle is how long it can fully charge and discharge energy. The more times it can do this, the longer it will last.

The average solar battery usually lasts for around 10 to 15 years. This is around half the expectancy of a solar panel system, so you may need to buy a solar battery twice during the solar system’s lifespan.

Installation Costs

Solar battery installation costs will vary depending on factors like the battery size, the property’s layout, and your location.

Some areas, like London, feature higher labour costs. Any additional equipment or modifications needed to integrate it with your existing solar panel system can also increase the costs.

It’s usually more economical to install the solar battery when installing your solar panels

What Are the Pros and Cons of Solar Panel Batteries?

Pros

  • Reduced Energy Bills – Storing energy in your battery reduces your reliance on the grid when your solar panels aren’t generating electricity, helping you reduce your energy bills.
  • Lower Carbon Footprint – A battery allows you to use more of your low-carbon energy and reduce your reliance on energy sources that negatively impact the environment.
  • Back-Up Power Source — A battery gives you greater freedom from the grid and can provide a reliable power source during outages or when the grid is in high demand.
  • Time of Use Tariffs – A battery allows you to use time of use tariffs when electricity is cheaper. You can store electricity when it’s more affordable and use it to avoid expensive periods.

Cons

  • Added Expense — The initial cost can be steep and can increase the overall cost of your solar panel system.
  • More Space Needed – You’ll need more space to house the battery and the connections.
  • You May Make Multiple Purchases — Solar batteries last 10 to 15 years, so you may need to purchase the battery at least twice to extend the lifespan of your solar panel system.

Final Thoughts

Although a solar panel battery can be an additional cost to your solar panel system, it can be a worthwhile investment in the long term, especially if you’re considering living a greener lifestyle.

Batteries allow you to use more of the electricity you generate from your panels and can help reduce your energy bills and carbon footprint by reducing your reliance on the national grid.

Sources and References

  • https://energysavingtrust.org.uk/advice/solar-panels/