The Regelleistung-Online platform once again queried data from grid operators and independently derived a total grid connection request volume of 470.5 GW from seven participants. According to the platform’s assessment, the over 500 GW of requests do not reflect a genuine boom in the battery energy storage market but rather indicate misdirection in the approval system.
The platform surveyed the current status of four transmission system operators (TSOs) and three distribution system operators (DSOs)—Edis, Westnetz, and Mitnetz—with the aggregated data reaching 470.5 GW. Germany has approximately 800 distribution system operators, with highly uneven regional distribution. Among the transmission system operators, 50 Hertz leads with connection requests of 103 GW, followed by Amprion with 86 GW—far surpassing Tennet's 52 GW and Transnet BW's 18 GW. The transmission side accounts for a total of 259 GW, with an additional 211.5 GW contributed by the distribution side.
Industry feedback emphasizes that the current grid connection process—due to the "first-come, first-served" principle, insufficient preliminary reviews, and time-consuming procedures—is creating legal uncertainties. Recommendations include improving grid connection checks through digitalization, establishing a unified online portal, introducing capacity auctions, and prioritizing projects based on their maturity to accelerate the expansion of energy storage.
Grid operators are already taking independent measures. For example, 50 Hertz has implemented feasibility checks to filter out unrealistic projects and is converting requests into option lists prioritized according to project maturity.In the first half of 2025, solar power generation in the UK reached a historic high. According to data from energy research firm Ember, solar generation in the first six months of the year reached 9.91 TWh, a year-on-year increase of 32%, setting new records for five consecutive months since March. This achievement is attributed to 2025 being the sunniest year on record in the UK, coupled with continued growth in installed solar capacity.
Latest statistics released by the Department for Energy Security and Net Zero (DESNZ) show that as of the end of July, the country's total installed solar capacity reached 19.1 GW, corresponding to approximately 1.8 million installation sites—an increase of 1.3 GW compared to July 2024. In July alone, 22,406 new solar projects were added, contributing 106 MW of new capacity, making it the fourth-highest month for solar additions on record. Excluding Northern Ireland, the grid-registered installed capacity in Great Britain stood at 18.7 GW.
The data also reveals a trend toward larger-scale solar projects in the UK: at least 42% of the capacity (8.1 GW) comes from ground-mounted or standalone projects. This includes 15 solar power stations supported under the Contracts for Difference (CfD) mechanism, 13 of which commenced operation in 2025.
Ember further highlighted that large-scale solar projects now account for nearly half of the newly added capacity, compared to just 5% between 2010 and 2019. In contrast, growth in small-scale rooftop solar has relatively slowed. As of the end of July, cumulative capacity for systems under 4 kW reached 4 GW, while systems between 4–10 kW reached 1.4 GW. So far this year, newly added capacity for these two categories of small systems was 258 MW and 226 MW, respectively, showing largely steady growth.
