As the UK plans to deliver on its Clean Power 2030 goals, the effective integration of battery storage systems will be a key component of this “Herculean” effort.
This was the opinion of Mike Thompson, chief economist at the National Energy System Operator (NESO), who spoke at the beginning of the final day of Solar Media’s Energy Storage Summit conference, held this morning in London. Thompson said that the challenge would be significant, but “just this side of impossible”, and laid out a number of deployment targets for the UK storage sector to help enable the clean energy transition.
“By 2030, batteries need to get to 23-27GW of capacity, and, of course, how the run rate changes, how the deployment we need to do year-on-year changes,” said Thompson, which would be a significant growth from the 4.6GW of capacity in operation as of June 2024.
“That’s going [to have to be] 2.5GW to maybe a bit over 3GW of storage additions a year in the UK every year to 2030, and alongside that more long-duration energy storage (LDES), distributed storage and other sources of flexibility.
“It will require us to do things different [and] have major reforms,” continued Thompson, who echoed arguments made on day one of the event that co-located solar-plus-storage is one of the most financially viable technology choices in the renewable energy sector. “But if we can get there, and we do deliver on it, then there are a lot of benefits to have – carbon benefits [and] investment benefits – and we can cut the link to gas prices.”
Year-round variation
Thompson also suggested that the UK’s use of storage would not protect the country from seasonal variation in its renewable energy mix. Rather than removing variation from the mix entirely, as has sometimes been suggested for storage in energy mixes dominated by variable electricity generation technologies, NESO’s forecasts for 2030 suggest that storage will play a different role at different points of the year.
“In the summer, there is fairly conventional role of storage: taking demand from peak periods of production and moving it to peak hours of consumption later in the day, moving about 50GWh a day,” explained Thompson. “That gets us close to that 20TWh over the course of a year figure.”
“In winter, you’ve got three days at the start where you have so much wind and solar output that you can’t absorb it all; you’re exporting it, maybe curtailing it, and you’ve got very low prices,” he continued, suggesting that some periods of the year could see the discrepancy between supply and demand of electricity measured in terawatt-hours. “You’ve then got this long period of three days where you’re having to use your gas; you’re going from a gigawatt-hour problem to a terawatt-hour problem.”
However, Thompson noted that storage would help minimise this discrepancy, calling it the “next frontier” to “deal with that terawatt-hour problem”.
“We think in our modelling that this will happen in five to ten periods throughout the year,” said Thompson. “You could have 3TWh at a time, actually, that you’re trying to fill.”
Storage versus fossil fuels
Thompson went on to discuss how storage would need to fit into an increasingly complex energy sector in the next five years.
“Of course, there will be times when supply and demand are not matched, so we will need to use gas for a backup for security of supply, but that will be less than 5% of generation over the course of the year,” said Thompson, who then called on the audience to vote as to whether they thought storage, or gas, would make a larger contribution to the GB energy mix by 2030. Just over half of the attendees voted in favour of storage, which matched NESO’s forecast for the remainder of the decade.
“In the NESO analysis for 2030, we have storage accounting for more than gas generation [including] the combination of storage and pumps together,” said Thompson.
The NESO economist also praised the UK government for introducing what he called “a mission and not just a target” for Clean Power 2030, which was announced last December and aims for the country’s clean energy facilities to generate at least as much power as GB consumes over the course of the year and be responsible for 95% of total electricity generation.
In his opening remarks ahead of the day’s sessions, Charles Lesser, partner at Alexa Capital, echoed this sentiment that the UK is setting the standard for working towards its clean energy targets, calling NESO “the most forward-looking grid operator in Europe”.
The Energy Storage Summit, hosted by our publisher Solar Media, takes place in London, UK, this week (18-19 February). Visit the event site for more details including the agenda and how to get tickets.
