As renewable capacity is added to the grid, the need to store and flexibly manage electricity grows with it. This is where the crucial role of battery energy storage systems (BESS) come into play, storing and releasing energy for when it’s needed most. We look at what’s happening with the growth of BESS in the UK.
A growing project pipeline
According to Solar Media Market Research the energy storage market is experiencing substantial growth, with the total operational capacity for projects in the UK now at 4.6GW. This is projected to increase to 7.4GW by the end of the year. What about planned projects? Renewable UK’s Energy Storage Report (Dec 2023) states that the total pipeline of battery projects increased from 50.3 gigawatts (GW) a year ago to 84.8GW, an increase of 68.6%. The number of BESS projects are growing, and so too is the size of the project.
Battery projects to shift in size
The data also suggests a shift towards larger projects, with the average size being submitted into the planning system in 2023 increasing to 80MW. A decade ago the average project size was just 2MW, and by 2021 it had grown to 54MW. When it energised in 2021, the 100MW/136MWh Minety development in Wiltshire was Europe’s largest operational battery storage project at the time. A year ago we saw planning permission granted for Carlton Powers’ 1,040 MW project — described as the world’s largest battery energy storage project — to be located at Manchester’s Trafford Low Carbon Energy Park. Earlier this month, Statera received planning permission for a 400MW BESS project near Chickerell in Dorset. The trend for bigger battery projects is clear.
The location factor: Where will we keep batteries?
According to Modo Energy’s analysis, the operational battery storage capacity in Great Britain is made up of 141 individual battery units located up and down the country. Their July round up suggested that this diversity in locations is revealing trends for battery operation. Locational factors for batteries are important because of the way that the project interacts with the local system. For example battery storage projects in Scotland can reduce wind curtailment by soaking up excess electricity that can’t go into the grid. Projects in the south can discharge when there is more demand than supply available locally. Location has a direct impact on how the BESS operates, and in turn how much revenue the project can make.
Benefits of battery co-location
Co-location of BESS is becoming more mainstream. These are projects where the renewable generation and the battery storage are combined at the same grid connection point. For example, a new solar farm might be co-located with containers of lithium-ion batteries to store their electricity generation. This can be more efficient from a grid connection point of view as the two technologies often complement each other well. During the wholesale electricity peak at the start or end of the day, there can be lower solar generation (depending on time of year) and this is when the battery comes in.
Developing a co-located project can also be cheaper than standalone BESS. Despite co-locating different technologies potentially bringing value to both industry and consumers, the UK currently only has a small percentage of co-located projects (around 12% of all installations according to Renewable UK Energy Pulse). This is due to various barriers and complexities with market, grid and planning as well as technical challenges around metering. Dealing with these issues would enable more co-located projects and with it increased flexibility and optimisation of renewables. It could be a key area to watch in the effort to accelerate the transition and achieve the government’s energy targets.
Time for innovation
The shift to a system powered largely by renewables requires more flexibility, agility and versatility. Instead of a few large fossil fuel generators switching on and off, we’re looking at a dynamic and open system. This creates opportunity for innovation, around technology, around data and around how and when electricity is used. In recent months, Octopus Energy signed a two-year fixed-price agreement with Gresham House Energy Storage Fund for 500MW of its battery assets. Under the arrangement Octopus Energy will pay a fixed fee per megawatt for the use of the battery storage projects, facilitated by their technology platform, Kraken. It’s believed to be the first such arrangement in the UK BESS market. It may be a sign of what’s to come as projects start to explore outside of the existing opportunities.
Electrifying demand
The transition away from fossil fuels doesn’t mean that electricity demand will reduce. In fact, it’s predicted that our homes and businesses will need even more electricity. Demand is set to at least double by 2050 – as we electrify sectors like transportation and heat. The future of a decarbonised UK depends on a smarter and much more flexible grid. Investing in battery storage now is vital to support growth in this key sector.
