In September 2024, battery energy storage systems in Great Britain earned average revenues of £37.5k/MW (annualized). This was 20% lower than in August - despite September 10th being the single highest-earning day of 2024 so far for batteries. However, one battery bucked this trend and earned higher revenues in September than it did in August - by maximizing its Balancing Mechanism availability.
Our market update discusses battery revenues, including Capacity Market earnings, on a £/MW/year basis. For monthly battery operations updates, we will discuss revenues excluding the Capacity Market. That’s because the Capacity Market does not impact operational strategies.
The highest-earning battery performed less Dynamic Regulation High than its competitors
Wishaw was the highest-earning battery in Great Britain in September. It combined wholesale trading with Balancing Mechanism dispatches to earn 33% more than average for a two-hour system. Wishaw also had fewer costs from performing Dynamic Regulation High than other high-earning two-hour systems, as it focused on importing energy in the Balancing Mechanism.
The highest-earning one-hour batteries were Capenhurst 4 and Lascar Works, which both outperformed the one-hour index by 33%. Both assets performed more Dynamic Moderation High than any other battery, and half as much Dynamic Containment High than average.
Batteries performed 15% fewer cycles in September, causing revenue to fall
Despite the link between cycling and revenue increasing in September, batteries opted to reduce their cycling. Two-hour systems cycled 0.9 times per day, a 25% decrease from August, as lower wholesale spreads reduced the revenue potential of a cycle.
For the second consecutive month, the relationship between cycles and revenues strengthened for one-hour batteries. This follows reduced Dynamic Containment clearing prices, which decreased the value of the low cycling service.
Dynamic Containment strategies resulted in lower revenue
Dynamic Containment is a low-cycling service. This means when clearing prices are high, it can break the link between cycles and revenue, as batteries can earn more through fewer cycles. When clearing prices are low, this strengthens the relationship between revenues and cycling as batteries earn less money for cycling less. Low clearing prices in September meant batteries that focused on Dynamic Containment generated lower revenues.