The role of battery storage in the UK’s net zero mission

Blog by Solar Energy UK member GivEnergy.

The UK government has enshrined in law a commitment to achieve net zero carbon emissions by 2050.

Part of this goal involves the full decarbonisation of power by 2035 – shifting from fossil fuels towards renewable energy, e.g. wind, solar, hydropower, etc.

On this front, significant progress has already been made, despite the recent announcement on allowing new gas plants to be built in the 2030s.

From 2010-2022, UK electricity generation from renewables grew from 26TWh to 135TWh. While this progress is commendable, it will count for little if the development of battery storage does not keep pace.

Use of battery storage at both grid and consumer level is a vital step to net zero. Energy storage helps offset the hour-to-hour variability of some renewables, and facilitates the increasing electrification of transport and heating (EVs, heat pumps, etc.)

Here, Dave Roberts, GivEnergy MD, explains the role of battery storage in the UK’s net zero mission.

Why is battery storage necessary to achieve net zero?

According to a report co-authored by Centre for Net Zero, consumer electricity demand in the UK is set to increase by around 50% by 2035.

This is being driven in large part by the electrification of:

• Transport – i.e., the increase in electric vehicles. The government plans to ban the sale of petrol and diesel cars by 2035.
• Heating – The government aims to increase installations of heat pumps to 600,000 per year by 2028. (Installation of traditional gas boilers in new build homes will be banned from 2025 onwards as part of the Future Homes Standard.)

Moreover, the renewables on which the UK is increasingly dependent – especially wind and solar – tend to have hour-to-hour variability. You can’t make the wind blow or the sun shine as and when required.

With battery storage, however, renewable energy can be stored and then discharged for later use. (Such as during times of peak energy demand.)

• Grid-Level

For a grid-level example of why renewables need battery storage, consider that during the winter of 2022-2023, the UK wasted enough wind energy to power 1.2 million homes. In short, an abundance of the wind energy generated had nowhere to go.

• Consumer-Level

To understand this problem at a consumer-level, take the following (all-too-common) scenario.

A household installs solar PV panels. During the day when the sun is shining, renewable energy is being generated. However, this is also the time when nobody’s home and therefore, electricity usage is low.

During the evening is when electricity demand peaks. Unfortunately, this is not when the sun is shining.

Without battery storage, there is no way for the household to store the solar energy generated during the day to be discharged later in the evening.

The role of grid-scale battery storage

The International Energy Agency (IEA) acknowledges that grid-scale storage is crucial for short-term balancing, as well as long-term energy storage.

The IEA also notes the following:

• Pumped-storage hydropower is still the most widely-deployed storage technology, but grid-scale batteries are catching up (battery storage capacity stood at around 28GW at the end of 2022)
• Grid-scale battery storage ‘needs to grow significantly’ to meet flexibility needs in a decarbonised electricity system
• To achieve net zero targets, grid-scale battery storage will need to increase to around 970GW by 2030

In a research paper by the Department for Energy Security & Net Zero, the UK government recognises the potential of the following types of storage batteries:

• Lithium-ion batteries (1-8 hours storage time)
• Flow batteries (4-8 hours storage time)
• Zinc batteries (1-6 hours storage time)
• Sodium sulphur batteries (1-6 hours storage time)
• Iron air batteries (up to 100 hours storage time)

Grid-scale battery storage in the real-world

Fortunately, this recognition is rapidly turning into real-world implementations. For example, the EnergyPulse Energy Storage report released in December 2023 by RenewableUK suggests that the pipeline of UK battery storage projects has grown by two-thirds over 12 months.

Capacity has gone from 50.3GW at the end of 2022, to 84.8GW a year later. (Including projects in the pre-planning, planning, consented, under construction, and operational stages.)

Meanwhile, according to a report by Aurora Energy Research, Britain is set to quadruple its grid-scale battery storage capacity by 2030.

And we can see this happening right now, in any one of many prominent examples. Take the grid-scale battery storage site in Pillswood, near Cottingham, East Yorkshire. The £75 million site can provide 196MWh of electricity in one cycle. That’s enough for 300,000 homes in Yorkshire.

The role of consumer-scale battery storage

Alongside grid-scale battery storage, a report by Centre for Net Zero also acknowledges the integral role that consumers can play in helping to achieve net zero targets through energy storage. Simply, storage needs to be implemented en masse in individual homes, too.

Some of the necessary infrastructure is already in place. In fact, according to figures from the Microgeneration Certification Scheme (MCS), around 1.3 million UK homes now have solar panels. For some, a wind turbine for home is also an option, though this comes with barriers regarding cost, practicality, planning permission, etc.

While this progress towards consumer-scale renewables is a step in the right direction, it’s not enough. Complementary battery storage is also necessary to ensure that energy generated isn’t wasted.  

Moreover, standalone battery storage (i.e., home battery storage without solar) can also bring benefits to the grid. Consumers on smart tariffs can charge during cheaper off-peak hours and discharge during peak hours. In turn, this helps to reduce strain on the grid when demand is at its highest.  

Consumer-scale battery storage in the real-world

The most recent available figures from 2019 show there were 10,000 home battery installations in the UK, though we can reasonably assume this has increased since then. 

Globally, the home battery storage market reached a capacity of around 34GWh by the end of 2023, according to Bloomberg. The market is expected to grow from a value of around USD5.4 billion in 2023 to around USD17.5 billion by 2028.

And this emerging market is already making a huge difference. Indeed, the ability of consumers in Great Britain to help balance grid demand has already been demonstrated through the Electricity System Operator’s (ESO) Demand Flexibility Service.

Introduced in the winter of 2022-2023, the Scheme rewards households and businesses for shifting electricity usage outside of peak hours. According to the ESO, over 3,300MWh of electricity was saved – enough to power 10 million households.

During the 2023-2024 Demand Flexibility Scheme, GivEnergy customers were able to participate. As part of GivBack, households could get paid to export the excess energy stored in their batteries during peak hours, ultimately helping to reduce strain on the grid.

GivEnergy CEO, Jason Howlett has previously advocated for the inclusion of battery storage in the Future Homes Standard (FHS) set to be introduced in 2025.

And according to a recent poll, this inclusion is supported by 61% of MPs. In the same poll, 79% of MPs supported mandatory solar panels in new build homes. As of press time, a consultation is ongoing.

A price drop for home storage batteries

While the specific details of the FHS regarding solar and storage hang in the balance, one thing is clear: home storage batteries are getting cheaper.

This is thanks, in part, to the UK government’s introduction of 0% VAT for the following:

• Battery storage coupled with solar
• Standalone battery storage
• Retrofit storage batteries

This will help make battery storage at consumer-level more accessible, and ultimately help enable consumers to contribute to balancing grid demand.

The pivotal role of battery storage in achieving net zero

It’s clear that for the UK to achieve its net zero mission, battery storage is essential at both grid- and consumer-level.

With the electrification of transport and heating, as well as the hour-to-hour variability of renewables, battery storage is essential in helping to balance grid demand.

Huge progress has already been made. This is true regarding the increasing number of grid-scale battery storage projects in the UK, as well as measures to encourage the uptick of consumer-level battery storage systems.

At the same time, we recognise that there are areas where further progress could be made. This includes the addition of mandatory battery storage in the FHS. 

Simply put, achieving the UK’s 2050 net zero targets will depend on battery storage. We need both large-scale battery storage facilities and battery storage systems in households and businesses across the country – and we need it fast.

About the author

David Roberts is UK Managing Director at GivEnergy – the company empowering energy freedom for all. GivEnergy is the largest British-owned manufacturer of residential and commercial battery storage systems. As well as batteries, the company’s range also includes inverters, EV chargers, energy management software, and a host of supporting accessories. Together, these products create an ecosystem for customers to control their energy end-to-end.