When it comes to battery storage, there are a lot of important factors to consider and whether that be installation costs, potential savings and battery selection, in this guide we cover them all.
Domestic battery storage is gaining popularity in the UK, particularly in response to the recent energy crisis, as more homeowners seek to reduce their energy bills and dependence on the grid.
Battery storage systems allow homes with solar panels to maximise their self-consumption by storing excess energy for later use.
Additionally, they enable households with or without solar panels to benefit from time-of-use tariffs by storing energy when it’s cheaper and using it during peak times.
But how much can you actually save by installing battery storage? And how long will it take to recoup the costs?
This guide aims to provide a comprehensive resource for anyone considering battery storage in the UK, covering the costs, and potential savings, and addressing the most common inquiries related to battery storage systems.
PS We offer MCS-certified battery installation nationwide. Simply answer these questions, get your fixed price and arrange your free design.
What is Battery Storage?
Domestic battery storage systems allow you to store electricity for later use, giving homes more control over when they use their energy throughout the day and night and when they draw it from the grid.
This means homes with battery storage can avoid the high costs associated with peak electricity demand periods and instead opt for time-of-use tariffs, such as Octopus Go.
It also means that homes with their own energy generation systems e.g. solar and/or wind turbines can store more of the energy they produce for use in the evenings.
This dual-source compatibility means that even on days when renewable energy is scarce, your battery can still be charged using grid electricity, ensuring a constant and reliable energy reserve.
Prefer video? Check out our YouTube video that explores whether installing a home battery to a solar array is worth it (spoiler: it is):
What are the different types of battery storage?
The most notable difference between battery types lies in the chemicals they use.
In the context of domestic battery storage, the two most common types are lithium-ion batteries and lead-acid batteries. However, there are other types available as well.
Here’s an overview of the most common types, along with their pros, cons, and potential costs in the UK:
Lithium-Ion Batteries (Latest Innovation)
Lithium-ion batteries are the gold standard when it comes to domestic battery storage.
Lithium-ion batteries are regarded as offering a high energy density, long lifespan and high efficiency and for this reason, are the most popular type of battery used in domestic storage systems, which includes the likes of the Tesla Powerwall.
Lithium-ion batteries are more compact, lightweight alternatives with higher performance ratings, faster charging speeds and a higher storage capacity per square centimetre.
Yes, that means they’re more expensive but they often come with much longer warranty periods compared to lead-acid batteries meaning, although the initial outlay is higher, you’re getting more bang for your buck.
Now looking at lithium-ion solar batteries, the average 4kWh product would cost about £4,000, twice as much as an average 4kWh lead-acid solar battery.
However, a 4kWh lithium-ion solar battery would offer around 4,000 lifecycles (a lifespan of around 10-11 years) and a Depth of Discharge (DoD) of 90%.
Moreover, the cost per kWh per cycle of an average 4kWh lithium-ion battery would be approximately £0.28.
Lead-Ion Batteries (Old-School)
Lead-acid batteries are another popular choice but are largely being out-competed by lithium-ion batteries due to the significant advantages lithium-ion offers.
However, lead-acid batteries are more affordable at around £2,000 on average, making them a viable option for households with a stricter budget.
Compared to lithium-ion batteries, lead-acid batteries have a lower energy density, a shorter lifespan, and are much heavier and larger.
These characteristics can make them less efficient and more cumbersome for certain applications, though their cost-effectiveness remains a strong selling point for budget-conscious consumers.
Other Battery Types (Typically Used in Commercial Applications)
While there are some other types of battery storage available, these are not typically used in domestic settings and are instead used for large-scale commercial applications.
These include the following:
Solid-State Batteries: Offering higher energy density and improved safety over traditional lithium-ion batteries, solid-state batteries are still in the development phase and are currently more expensive, making them suitable for specialised commercial and industrial applications.
Flow Batteries: Storing energy in liquid electrolytes contained in external tanks, flow batteries can be easily scaled up by increasing the size of the tanks. This makes them ideal for large-scale energy storage solutions such as grid storage and renewable energy integration, rather than domestic use due to their size and complexity.
Sodium-Sulfur (NaS) Batteries: Known for their high energy density and long discharge times, NaS batteries are often used in large-scale energy storage applications such as grid stabilisation and renewable energy storage. Their high operating temperatures and safety concerns make them unsuitable for residential use.
Nickel-Cadmium (NiCd) Batteries: While durable and able to perform well in extreme temperatures, NiCd batteries are more commonly found in industrial applications due to their toxicity and the environmental challenges associated with cadmium.
Zinc-Bromine (ZnBr) Batteries: These flow batteries are effective for large-scale storage due to their scalability and long cycle life. However, the complexity and cost of the system make them more suitable for commercial and industrial use rather than domestic settings.
Explore a Battery Storage Case Study: Check out an insightful Q&A session featured in one of our detailed case studies on battery storage. Hear directly from a Heatable customer in the UK and gain valuable perspectives on their experience here.
The image above features a Tesla Powerwall 3 installation performed by our team of Tesla-certified installers at Heatable.
How much can you save with battery storage?
The energy and money you can save with battery storage depend on whether you are using it in conjunction with solar panels or independently.
For homes with battery storage only (i.e. no solar):
For those using battery storage without solar panels, significant energy savings can be achieved by taking advantage of time-of-use tariffs.
Modern smart-controlled batteries can be programmed to charge during the night when clean, renewable energy is more abundant and less expensive from the grid.
This green energy is approximately three times cheaper than peak daytime rates when demand is highest.
By using your smart home energy storage battery to store this inexpensive energy, you could potentially reduce your energy bill by up to 75%.
Additionally, battery storage allows you to take advantage of flexible energy tariffs.
For instance, Octopus Energy’s current Smart Export Guarantee (SEG) rate is 12p per kWh, which is one of the best rates available.
For an in-depth analysis of top battery storage systems, consult our comprehensive best solar battery guide.
For homes with solar panels:
According to the MCS self-consumption tables, households with solar arrays but without battery storage typically consume only about 20-35% of the energy they generate. The remaining energy, not used by the household, is exported back to the grid.
By installing a home solar battery storage system, MCS estimates that households can consume between 57-87% of the energy produced.
With a larger battery, this consumption can potentially reach 100%.
Furthermore, households can earn money from surplus energy produced by their solar panels through the Smart Export Guarantee (SEG). However, this is generally a less financially favourable option.
The SEG typically pays between 3 and 8 pence per kWh, whereas the cost of purchasing electricity from the grid can exceed 33 pence per kWh.
This significant price disparity means that you could be paying up to 11 times more for the energy you buy from the grid compared to what you earn from selling your excess solar power.
Therefore, it is often more economically sensible to store surplus energy in a battery system rather than exporting it back to the grid.
Utilising stored energy reduces reliance on the grid and can provide greater savings, particularly during peak pricing periods.
What size battery storage do you need?
The capacity of solar batteries is quantified in kilowatt-hours (kWh) and this is the total amount of energy they can store.
We have a complete guide on this here, but as a quick reference, see the tables below:
If you have solar panels installed, here is the battery capacity you likely require:
Annual energy consumption (KWh) | Number of panels | Battery capacity required |
2500 | 8 | 5-7 KWh |
3500 | 10 | 8-10 KWh |
5000 | 14 | 11-16 KWh |
If you don’t have solar panels, here is the battery capacity you likely require:
Annual energy consumption (KWh) | Battery capacity required |
2500 | 6-9KWh |
3500 | 10-13KWh |
5000 | 13KWh – 18KWh |
How Much Do Storage Batteries Cost?
The cost of a home battery storage system can fluctuate based on several variables, such as the capacity of the battery you need and the manufacturer you select. Generally, prices are situated between £5,500 and £7,500.
For a comprehensive and tailored cost assessment, including installation, you can obtain an instant fixed-price quote by following the provided link.
In an encouraging development, as of February 2024, the UK Government has eliminated VAT on all battery storage systems.
This policy change translates to a substantial 20% reduction in prices compared to those in 2023, making these systems more affordable for homeowners.
Below is a simplified price guide table for your reference:
Brand | Model | Capacity (KWh) | Charge/Discharge rate (KW) | Warranty | Price (estimated) | Inbuilt inverter |
Tesla | 13.5 | 5 | 10 years | £6995 | Yes | |
Tesla | 13.5 | 11.1 | 10 years | £7395 | Yes | |
Alpha | Smile 5 | 11.4 | 5 | 5 years | £3895 | No |
Alpha | G5 | 10.1 | 5 | 10 years | £4245 | No |
Enphase | 5.0 | 3.24 | 15 years | £2875 | Yes | |
GivEnergy | 13.5 | 6 | 12 years | £5500 | Yes |
Table prices: last updated June 2024.
Which Battery Storage System Should You Choose?
Selecting the optimal battery system involves evaluating a range of crucial metrics, each contributing to the overall performance, longevity, and cost-effectiveness of the battery.
The key parameters to consider include the following:
Max AC Power Output: This metric represents the peak power a battery can deliver at any moment, measured in watts (W) or kilowatts (kW), indicating the battery's ability to meet high energy demands.
Charging Capacity: This refers to the maximum rate at which a battery can be charged, essential for understanding how quickly the battery can be ready for use.
Depth of Discharge (DoD): DoD indicates the percentage of the battery's total capacity that has been utilized. A higher DoD means more of the battery's stored energy can be used, affecting its lifespan and efficiency.
Battery Weight: The mass of the battery can impact installation options and suitability for certain locations.
Lifecycle (Number of Cycles): This figure denotes the total number of complete charge-discharge cycles a battery can perform before its capacity falls below a specific percentage of its original capacity, offering insight into the battery's longevity.
Installation Flexibility: Whether a battery can be mounted on a wall, placed on the floor, or both, affects the integration with existing spaces.
Warranty Period: The duration and coverage of the manufacturer’s warranty can provide peace of mind and protection against premature failure.
Cost: The upfront and long-term costs of the battery system are critical for calculating return on investment.
Physical Size and Design: The dimensions and aesthetic design of the battery may influence the decision based on space constraints and visual preferences.
Among the myriad options available in the market, Tesla and Alpha ESS stand out for their notable contributions and advancements in battery technology.
Tesla is renowned for its superior battery chemistry, which minimises degradation over time and ensures construction to the highest standards.
On the other hand, Alpha ESS, known for its exceptional monitoring systems, offers products that, while less expensive than Tesla’s offerings, do not compromise on quality and efficiency.
Although Alpha ESS may not boast the same brand recognition as Tesla, the world's largest battery producer, it remains a competitive choice for those seeking premium quality at a more accessible price point.
For an in-depth analysis and comparison of the top storage batteries, including those from industry leaders like Tesla and Alpha ESS, consider exploring our comprehensive review of the best storage batteries.
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Next Steps For Your Battery Journey:
When planning to install battery storage for your home, there are several important factors to consider. Make sure to refer to the following guides to help you make informed decisions:
To dive deeper into these topics, head over to our advice section, check out our YouTube channel for informative videos, or read a customer case study to see how others have benefited from their battery installation.
Get a Quote for Battery Storage Today
Without boasting you should get your battery storage installed with us, here's why:
Thousands of Happy Customers: We boast an average score of 4.9 on Trustpilot, outperforming the market leader.
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Tesla Certified Installer: Heatable is proudly certified and approved by Tesla to install the Powerwall.
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Flexible Payment Options: Choose from multiple payment methods, including finance options.
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Save Your Quote: You can save your quote and decide later.
Bespoke Battery Quote Tool: Find out which battery is ideal for your home, here.
