Hull Street Energy expands US power portfolio with 1.3 GW acquisition

Private equity firm Hull Street Energy (HSE) has completed the acquisition of two US peaking power generation facilities from Rockland Capital, representing a combined capacity of 1.26 GW (HSE press release, 26/08/2026). The transaction covers the 677 MW Lee County Generating Station, a natural gas-fired power plant in Illinois, and the 586 MW Tait Electric Generating Station, a dual-fuel gas and diesel power plant in Ohio. Located within the Pennsylvania-Jersey-Maryland (PJM) electricity market, both facilities provide additional generation capacity and operational flexibility to address fluctuations in electricity demand and supply, according to the company’s press release. 

“Dispatchable resources are increasingly important as the resource mix becomes more intermittent and demand grows. This is particularly true in PJM where declining reserve margins are increasing the need to retain and improve assets like Lee and Tait,” said a Founder and Managing Partner of Hull Street Energy.

The two assets, collectively referred to as the “GridFlex Portfolio,” will be integrated into Milepost Power, HSE’s thermal power generation platform. Following the acquisition, HSE’s Milepost Power fleet will comprise nearly 5,000 MW of highly efficient and reliable gas-fired and dual-fuel generation capacity, positioning the company among the largest privately held power producers in the United States, the press release said.

HSE is also expanding its footprint in the US power sector. In May 2026, the company signed an agreement to acquire clean energy producer FirstLight USA from the Public Sector Pension Investment Board. The deal involves nearly 1.4 GW of power generation assets in the north-eastern US, including Northfield Mountain, a 1.17 GW pumped-storage hydropower facility in Massachusetts, 14 hydropower plants across Connecticut, Massachusetts and Pennsylvania, and three operational solar and battery facilities in the region.