Seven two-hour batteries in England sold high volumes of energy in the wholesale market in July 2026, then bought it back in the Balancing Mechanism. All seven finished in the month's ten highest earners, 22% to 31% above the two-hour index.

Scottish batteries have run this trade for years, but always behind a transmission constraint. These seven ran it without one: 99.5% of the energy they bought back was ordinary energy balancing, not constraint management.

They did it most during the morning solar ramp. Those four hours produced 83% of their energy-trading advantage over every other two-hour battery.

For subscribers to Modo Energy's Research, this article will also cover:

• Why this looks like a Scottish strategy but is not constraint-driven
• Why the summer solar ramp created the conditions for it
• Which technologies NESO bought energy back from at dawn
• What made these seven batteries better at it than everyone else
• Why batteries are the cheapest downward flexibility on the system, and how that saved consumers £3.5m in July
• A data download of all charts

This trade was not constraint-driven

The strategy of re-trading energy sold in wholesale and buying back in the Balancing Mechanism is familiar. Scottish batteries sell into the wholesale market and get bought back when the transmission network cannot move their output south, a pattern NESO is examining closely, and one Modo Energy covered in Four batteries 20 miles apart beat the ME BESS GB Index in January.

Unlike in Scotland, where batteries bought 52% of Balancing Mechanism energy behind a constraint in July, the seven southern batteries bought 99% of their energy without an active constraint.

In March, Scottish batteries were taking two and a half times the Balancing Mechanism energy these seven were. By July, the seven had overtaken them almost four times over, and the crossover tracks the move into summer: the seven assets we are focused on bought 28 MWh/MW in March and 98.5 in July, while Scotland's constraint volume fell from 71 MWh/MW to 27 over the same months.

The morning solar ramp became the biggest window for the trade

The shape of the day changed between March and July. In summer, the morning is when GB has the most surplus power and the least plant able to turn down, so that is where NESO looks for turn-down, and where the seven units did their trading.

During the morning solar ramp in July, these batteries re-traded 6.7 GWh, 42% of everything they re-traded (between wholesale and BM) that month.

Between 05:00 and 09:00, 86% of all these units bid volume came from a re-traded export in July, against 69% in June.