Maximise your solar panel output with a battery. Here’s all you need to know about finding the best solar panel batteries for your needs.
Looking for the perfect solar panel batteries to power up your home? You're in the right place — battery storage can help you get the most out of your solar panels. By storing surplus electricity, these batteries allow you to enjoy a consistent power supply at night and on dark winter days.
Whether you need a battery for your home solar panels or a commercial solar system, our guide is here to walk you through the ins and outs of these handy installations. Read on to discover the types of solar panel batteries available, their costs, and how to find the ideal setup for your needs.
Once you have all the information you need, we encourage you to make use of our convenient solar panel comparison tool. With SpotDif, the comparison process is fast and easy — we’ll compare various solar panel battery providers so you can find the right fit for your solar setup and budget.
Are you a homeowner?
We all know that solar panels are a great way to embrace renewable energy and save money — but there’s a key element of solar power that many of us are less aware of. Solar panel batteries make harnessing the sun’s rays even more productive. They capture and store the abundant energy the sun provides for use at your convenience. But how?
During the day, your solar panels will be diligently absorbing sunlight and converting it into electrical energy. (Remember, solar panels can still work on cloudy days — they absorb ambient light, not just direct sunlight.)
Often, the energy your photovoltaic (PV) panels generate exceeds your household’s immediate needs. This excess energy is where solar panel batteries excel. They store this surplus, making it available for later use, especially during periods when sunlight is scarce, such as at night or in the winter when the sun rises later and sets earlier.
The technical workings of these batteries revolve around converting and storing energy. Solar panels capture solar energy and convert it into direct current (DC) electricity. However, most homes and appliances operate on alternating current (AC). An inverter transforms DC into AC so you can use the stored energy at home.
For an in-depth explanation of the storage process, why not discover how solar batteries work?
There are two main types of solar batteries in the UK.
Lithium-ion batteries stand at the forefront of solar battery technology. They store energy through lithium ions moving between electrodes — a highly efficient process. This efficiency means they can store more energy in a smaller space, making them ideal for homes with limited space.
Though they have a higher upfront cost than other battery types, their durability and efficiency can lead to cost savings over time.
Price: Lithium-ion solar batteries generally cost from £3,400 to £6,000.
Lifespan and maintenance: Their advanced technology of lithium-ion solar batteries ensures a longer lifespan, often up to 10-15 years, and they require minimal maintenance.
Lead-acid batteries, the veterans of solar storage, operate by a chemical reaction between lead plates and sulphuric acid. This traditional technology is more straightforward and thus less expensive to manufacture. They are larger and heavier than lithium-ion variations, which means they require more space.
Lead-acid batteries are a cost-effective solution for those with larger installation spaces and a tighter budget.
Price: The average cost of a lead-acid solar panel battery in the UK ranges from around £1,500 to £3,000.
Lifespan and maintenance: With an average lifespan of five to seven years, they don't last as long as lithium-ion. They also require more maintenance and TLC to keep them running optimally.
While not a different type of solar battery, solar panel battery banks refer to a group of batteries linked together within a solar power system. This setup is designed to store excess energy generated by your solar panels.
The beauty of a solar panel bank is its capacity to hold large amounts of energy, ensuring a reliable power supply even when the sun isn’t shining. It's especially useful for off-grid systems or in areas with unreliable power sources. By having multiple batteries connected, you can store more energy, providing greater energy security and efficiency for your home or business.
Wondering what happens when your solar panels produce surplus energy? It all depends on your setup.
Grid-connected solar systems direct excess energy to the grid. This means that no energy is wasted and you even get paid for your solar energy. This can come as payments or as credits to offset any future payment to the electrical grid.
Some systems are built with a backup ‘store’, which receives the excess energy once your battery has reached its capacity. This can be another battery or other device with the capacity to store energy. Ultimately, this means no energy is wasted.
The excess energy can be redirected back into the solar panels. The idea here is to manage the power flow to prevent it from damaging the system. This is sometimes known as ‘curtailment’ or ‘clipping.’ This energy is effectively lost as it is no longer stored to power your home.
Once you know which kind of batteries you want for your solar panels, it’s time to think about quantity.
There’s no one-size-fits-all approach to this but as a general rule:
One battery is enough for an average UK home’s backup power
Two to three batteries will help you avoid peak electricity bills
10 solar panel batteries or more will help you go off-grid.
The longer answer is that it depends on several factors, including your energy usage, the capacity of your solar panel system, and the type of batteries you choose. So how do you work out if one solar battery is enough?
Firstly, consider your daily energy consumption. How much power does your household typically use? This is measured in kilowatt-hours (kWh) and can be found on your electricity bill.
Next, look at the capacity of your solar panels. How much energy can they generate on an average day?
We recommend thinking about the batteries themselves, too — different types have varying capacities, usually measured in kWh. Lithium-ion batteries, for instance, tend to have a higher capacity than lead-acid.
The idea is to have enough battery storage to cover your energy needs when the solar panels aren't generating power, like at night or during cloudy days. However, you may wish to invest more if you want to fully embrace an off-grid lifestyle.
Are you a homeowner?
If you’re thinking about solar panel installation, you might be wondering if you can have solar panels without a battery. You absolutely can install solar panels without a battery — they are not a compulsory component.
However, we recommend exploring the benefits of solar panel batteries before writing them off as an extra cost.
Although a battery isn’t a requirement for solar panels, it can bring a host of benefits to homeowners and businesses alike.
The most prominent benefit of adding a battery to your solar panel system is the potential energy bill savings. Solar batteries help you make the most of the solar energy you collect. Because it’s in storage, you can use it during peak demand times when electricity rates are higher.
Experts have worked out that a solar panel battery could save you as much as £800 per year.
Another perk of installing a solar panel battery is the independence it gives you. With less reliance on the National Grid, you can get a consistent power supply even during outages.
If you’re looking to lower your environmental impact, solar battery storage helps reduce reliance on fossil fuels by maximising your use of renewable solar energy.
With the UK’s move towards Net Zero, the government is keen for more households to embrace solar panels and batteries. With this in mind, there are some helpful solar grants and schemes to make installation more accessible.
We recommend exploring our guide to solar panel grants to see what’s available and what your household or business might be eligible for.
At SpotDif, we believe getting a balanced view of home improvements is important before investing. As such, we recommend noting the potential drawbacks of solar batteries. In our experience, these include:
A higher upfront cost: Installing a battery for your solar panels is a significant investment, adding a few thousand pounds to your setup. This can be a barrier for some households hoping to integrate battery storage.
Space requirements: You also need a dedicated area for your battery, which can take up anywhere from 1.2 square metres (12 square feet), including requisite space around the battery unit.
Lifespan: While solar panels can last for over 20 years, solar batteries tend to have a lifespan of between five and 15 years, meaning you will likely need to replace your battery long before updating your solar panels. Replacement will add to your long-term battery costs.
It’s time to look at another vital factor in choosing batteries for your solar panels — the cost.
Prices vary, starting from as little as £1,000 but the average cost for a solar battery tends to be around £5,000 to install on its own or £2,000 to £3,000 if you install it at the same time as your solar panels.
So, what causes this price variation?
As we mentioned, lithium-ion batteries tend to be more expensive than lead-acid ones, with the former costing from £3,400 to £6,000 and the latter coming in at around £1,500 to £3,000.
Size matters too. Your solar battery’s storage capacity will be measured in kilowatt-hours (kWh), and the higher the capacity, the more energy it can store. Generally, a larger capacity also comes with a higher price tag. On average, you should expect to pay around £900 per kWh of storage capacity.
The average cost of a 5 kWh solar battery is roughly £5,000, including the price of installation and an inverter. However, if you add that 5 kWh battery onto a solar panel installation, its price generally falls to between £2,000 and £3,000, as you’re already paying for the labour and an inverter.
Likewise, a 10 kWh battery might cost £7,000 by itself, on average, but if it’s part of a solar panel and battery kit, its price typically drops to £4,000 to £5,000.
In many cases, you’re better off making all your planned changes to your home at once — otherwise, you’ll end up paying more than you need to.
As with many products and services, the price of your battery will also depend on the manufacturer. A well-known solar company with better warranties and support services may command higher prices.
We suggest exploring quotes from different solar panel and battery companies to get a good idea of your options. And don’t forget, we’re always on hand with our comparison tool to help. We’ll do all the research for you, bringing you a list of offers from trusted suppliers.
Often, solar panel batteries that have less maintenance — and therefore come with more comprehensive warranties — cost more. The higher price comes from the reduced risk for you, the customer.
At SpotDif, we're here to help you make sense of all the costs involved with solar panel batteries and battery installation. We provide comprehensive comparisons of different solar panel batteries, taking into account their type, capacity, and overall value for money. Our goal is to find you a solar battery solution that aligns with your energy needs and financial plans.
If you’re keen to harness the power of the sun, we recommend using our helpful starting your search for a solar battery provider by using our handy comparison tool.