Executive Summary
Hull Street Energy (HSE), a private equity firm focused on power infrastructure, has completed the acquisition of two natural gas peaking plants totaling 1,263 MW in the PJM market from Rockland Capital. The assets—Lee County Generating Station (677 MW) in Illinois and Tait Electric Generating Station (586 MW, dual-fuel) in Ohio—will join HSE’s Milepost Power thermal generation platform. With this acquisition, HSE now owns nearly 5,000 MW of dispatchable generation capacity, making it one of the largest privately held power producers in the U.S.
The Players
Hull Street Energy is a private equity firm founded in 2014 and headquartered in the Washington, D.C. metro area. It specializes in deploying capital into the power sector during decarbonization and load growth. Unlike distressed-asset specialists (SVP) or financial engineers (Apollo/Blackstone), HSE focuses on operational value creation within existing assets. Its Milepost Power platform is a dedicated thermal generation operating company.
Rockland Capital is the seller, based in The Woodlands, TX. Founded in 2003, Rockland focuses on control investments in critical power generation, often targeting “undermanaged, undervalued, distressed” assets requiring operational optimization. This sale suggests Rockland has completed its value-creation plan for these plants and is recycling capital.
So What?
This acquisition validates three critical trends:
First, peaking plants are strategic assets. Historically, gas peakers (plants that run only during high-demand periods) were considered less valuable than combined-cycle baseload plants. But with AI driving load growth and renewable intermittency creating volatility, peakers provide critical grid reliability. PJM’s declining reserve margins are driving up capacity prices and making these assets more valuable.
Second, private equity is consolidating the power sector. HSE’s Milepost Power platform, with nearly 5,000 MW, is a roll-up strategy. The acquirers are not utilities or strategic buyers—they are financial players aggregating assets for operational efficiency and scale.
Third, dual-fuel capability is now a premium feature. Tait Electric is a dual-fuel facility (natural gas and oil), providing even greater operational flexibility during gas supply disruptions or price spikes. As fuel supply chains become a concern (recall the GE turbine shortages), the ability to switch fuels adds a risk premium to the asset.
What Should You Do With This?
If you are a power plant owner (independent or utility): HSE’s acquisition is a signal that the market for dispatchable assets is strong, with private equity buyers willing to pay for operational flexibility and PJM exposure. If you own assets in capacity-strained regions (PJM, ERCOT, MISO), consider a sale process now—valuations may be peaking.
If you are a private equity firm focused on infrastructure: HSE’s model—acquire and aggregate peaking plants into a dedicated platform—is proven. To win deals, you need (1) operational expertise (Milepost), (2) ability to move quickly (equity from managed funds), and (3) a thesis on capacity market pricing.
If you are a developer of new gas plants: this acquisition shows that existing peakers have a leg up on new-builds. HSE bought 1.2 GW of capacity that is already online, interconnected, and earning capacity payments. Your new plant faces 3-5 years of development risk. Consider acquiring and repowering existing peakers instead of building greenfield.
Source: Hull Street Energy press release, August 26, 2026
