Hull Street Energy
Hull Street Energy is a Bethesda, Maryland-based private equity firm founded in 2014 that invests in middle market North American power generation, storage, and transition assets, managing approximately $4.6 billion across three institutional funds and operating portfolio companies spanning gas, hydro, BESS, and solar EPC.
- Company typePrivate
- Founded2014
- HeadquartersBethesda, United States
- Headcount11–50
- GTM typeB2B
- OfferingServices
What Hull Street Energy does
Hull Street Energy (HSE) is a Bethesda, Maryland-based private equity firm founded in 2014 that specializes in deploying capital into the North American power sector as it decarbonizes. The firm invests in renewable and fossil-fueled power generation, energy storage, transmission and distribution, and demand-side businesses, with a focus on middle market power assets. HSE raises institutional private equity funds (Fund I in 2019, Fund II in 2022, and Fund III closed at approximately $2.2 billion in April 2025) and earns management fees and carried interest, with cumulative capital raised exceeding $5.0 billion and assets under management of approximately $4.6 billion.
HSE operates a platform-plus-modules architecture, owning or controlling a portfolio of distinct operating companies. The Milepost Power fleet owns and operates approximately 3.6 GW (expanding toward ~5,000 MW pending the Rockland Capital and FirstLight transactions) of natural gas-fired and dual-fuel generation in Texas, California, New York, Massachusetts, Connecticut, New Jersey, Illinois, Ohio, and Pennsylvania. The hydroelectric platform spans Confluence Hydro (Michigan 13-dam, 132 MW acquisition from Consumers Energy), Central Rivers Power (legacy 343 MW, sold to LS Power in 2022/2023), and the pending FirstLight USA acquisition (approximately 1,400 MW in the Northeast, including the 1,168 MW Northfield Mountain pumped storage facility). Energy storage is pursued through Serium Energy Storage (underground closed-loop pumped storage), Flatiron Energy (4.5 GW utility-scale BESS IPP in the Northeast), and TruGrid (utility-scale BESS and solar EPC contractor, headquartered in Houston, Texas). Renewable development is handled through Greenskies Clean Focus (commercial solar, storage, microgrids, CCHP), and environmental liability transfer through ETEM, which acquires and remediates retired or operating fossil generation. HSE also holds strategic investments in Upstream Tech (HydroForecast ML-based water/river flow forecasting and Lens satellite/aerial imagery platform).
HSE's go-to-market relies on direct origination of M&A opportunities from utilities, IPPs, infrastructure funds, and developers, supported by financial advisors and legal counsel relationships, with capital raised globally through placement agents (Eaton Partners for Fund I, Campbell Lutyens for Fund III). The firm leverages a senior team that worked together for over two decades at Goldman Sachs and Constellation Energy Group, combined with proprietary quantitative valuation techniques, analytical tools, and risk-management systems, and a government affairs team supporting federal and state regulatory strategy. Distribution of operating output occurs through wholesale electricity markets (PJM, ERCOT, New England) and long-term PPAs, with EPC services sold to developers, utilities, and asset owners across North America.
Hull Street Energy firmographics
Firmographics- Name
- Hull Street Energy
- Legal name
- Hull Street Energy, LLC
- Website
- http://hullstreetenergy.com/
- Company type
- Private
- Founded year
- 2014
- Operating status
- Operating
- Headcount range
- 11–50 employees
- Short description
- Hull Street Energy is a Bethesda, Maryland-based private equity firm founded in 2014 that invests in middle market North American power generation, storage, and transition assets, managing approximately $4.6 billion across three institutional funds and operating portfolio companies spanning gas, hydro, BESS, and solar EPC.
- Ownership category
- akta.pro rank
Hull Street Energy industry classification
Industry- Product category
- Power Sector Private Equity
- akta.pro primary industry
- Energy & Power Infrastructure Funds (Generation, Transmission, Storage) (FSANAEAB)
- akta.pro secondary industries
- Renewable Energy Infrastructure (FSAAAKAG), Real Assets — Energy & Power Infrastructure (Renewables, Conventional, Storage) (FSAHAIAD)
Keywords
Where Hull Street Energy is headquartered
LocationHeadquarters
- HQ city
- Bethesda
- HQ country
- United States
- HQ region
- North America
Offices3 records
Markets served
Hull Street Energy business model
Business model- GTM type
- B2B
- Offering type
- Services
- Cost components
- Personnel, Operations, Technology or R&D, Marketing or Sales, Others
Revenue model
- Private equity fund management fees and carried interest: HSE is a private equity firm that raises institutional funds (e.g., Hull Street Energy Partners III, L.P. closed at approximately $2.2 billion in 2025) and earns management fees and carried interest on these funds. Institutional LPs include endowments, foundations, insurance companies, pension plans, asset managers, and family offices. Since inception, HSE has raised over $5.0 billion in equity and debt capital across its funds.
- Power generation and storage asset revenue (through portfolio companies): Through affiliates and portfolio companies (Milepost Power, Central Rivers Power, Confluence Hydro, Flatiron Energy, Foundation Solar Partners, Greenskies Clean Focus), HSE owns and operates renewable, gas-fired, and dual-fueled generation capacity, hydroelectric plants, solar projects and battery storage assets that sell power and capacity into wholesale markets, under PPAs, and via net metering.
- EPC, O&M and construction services (through TruGrid and SunGrid): Portfolio companies TruGrid and SunGrid provide utility-scale engineering, procurement, construction (EPC) and O&M services for BESS and solar projects across North America, with most recent deployment of more than 500 MWh of battery storage.
- Asset dispositions / investment realizations: HSE realizes returns through periodic asset sales, including sales of Central Rivers Power to LS Power, the SunGrid PowerPlay portfolio to Generac, the Montana natural gas-fired plant, and Foundation Solar Partners. Sale proceeds generate capital gains and management fees.
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Other | Multi-year contract | Hull Street Energy Partners III, L.P. (Fund III) — oversubscribed institutional fund with ~$2.2 billion in total commitments |
Go-to-market motion2 records
Distribution channels4 records
Marketing channels5 records
Hull Street Energy product offering
Product offeringCore offering
Hull Street Energy is a private equity firm that makes controlling equity investments in middle market power businesses in North America, deploying capital into the power sector as it decarbonizes. The firm owns and operates a portfolio of renewable, gas-fired, and energy storage generation assets through subsidiaries such as Milepost Power, Confluence Hydro, and Flatiron Energy, and provides utility-scale EPC services through TruGrid and SunGrid Solutions. HSE has raised over $5.0 billion in equity and debt capital across three institutional funds and currently manages approximately $4.6 billion in AUM.
Product overview
Hull Street Energy (HSE) is a private equity firm, founded in 2014 and headquartered in the Washington, D.C. metropolitan area (Bethesda, MD), that specializes in deploying capital into the North American power sector as it decarbonizes. Its offering is best described as a platform-plus-modules architecture: a private equity platform that acquires, optimizes, and grows middle market power businesses, surrounded by a portfolio of distinct operating companies and platforms that HSE owns, controls, or has strategic investments in. The core thermal power business is operated through the Milepost Power fleet, a ~3.6 GW (expanding toward ~5,000 MW) portfolio of natural gas-fired and dual-fuel generation across the U.S. The hydroelectric business is operated through Central Rivers Power (343 MW across 47 plants, pending sale to LS Power) and the newly formed Confluence Hydro (Michigan 13-dam, 132 MW acquisition from Consumers Energy). Energy storage is pursued through Serium Energy Storage (underground closed-loop pumped storage), Flatiron Energy (utility-scale BESS IPP), and TruGrid (utility-scale BESS and solar EPC contractor). Renewable development is handled through Foundation Solar Partners (utility-scale solar in PJM) and Greenskies Clean Focus (commercial solar, storage, microgrids, CCHP). Environmental liability transfer is handled through ETEM. The firm also holds a strategic investment in Upstream Tech, whose HydroForecast (ML-based water/river flow forecasting) and Lens (satellite/aerial imagery monitoring) software products serve HSE's water- and asset-management needs. HSE has raised over $5.0 billion in equity and debt capital across its funds and manages approximately $4.6 billion in AUM.
Differentiator
Problem solved
Functional benefit
Brands
- Milepost Power: Milepost Power owns and operates natural gas fired combined cycle, simple cycle and reciprocating engine power plants, providing critical reliability service to the electricity grid.
- Central Rivers Power
- Confluence Hydro
- Serium Energy Storage
- Foundation Solar Partners
- TruGrid
- ETEM
- Flatiron Energy
- Greenskies Clean Focus
- SunGrid Solutions
- Upstream Tech
Products and services
- Hull Street Energy Partners III, L.P. (Fund III)
- Milepost Power Holdings
- Confluence Hydro
- Flatiron Energy
- TruGrid
- SunGrid Solutions
- ETEM (Energy Transition and Environmental Management LLC)
- Serium Energy Storage
- Upstream Tech HydroForecast and Lens Software
- Greenskies Clean Focus
Quantifiable outcome
- Optimized over 4 GW of operating renewable and gas-fired generation assets and advanced development of ~10 GW of new renewable, gas-fired, and storage resources
- +5 more outcomes
Companies that use Hull Street Energy
Customer profileNamed customers16 records
Segments4 records
Ideal customer profiles3 records
Hull Street Energy technology and API
TechnologyTechnology focussed No
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Integration1 record
AI capability6 records
Feature5 records
Hull Street Energy partnerships and signals
Strategic signalPartnerships
18 partnerships are on record, tiered core and flagship.
- Rockland CapitalcoreRockland Capital, a private equity firm focused on control investments in critical power generation assets in the U.S. and U.K., is selling two PJM power plants (Lee County Generating Station, 677 MW, Illinois; and Tait Electric Generating Station, 586 MW, Ohio) to Hull Street Energy. PEI Global Partners, LLC and Houlihan Lokey acted as financial advisors and Bracewell acted as legal counsel to Rockland; Troutman Pepper Locke acted as legal counsel to HSE. The acquisition expands Milepost Power fleet to nearly 5,000 MW.
- Consumers EnergycoreConsumers Energy (Michigan's largest energy provider) is selling 13 hydroelectric dams (132 MW combined) to HSE's newly formed wholly owned subsidiary Confluence Hydro. Under a 30-year power contract, Confluence Hydro will provide power back to Consumers Energy. Transaction is subject to state and federal regulatory approval and expected to close in 12 to 18 months. McGuireWoods, LLP, Rock Creek Energy Group, LLP, Varnum, LLP and Potomac Law Group, PLLC acted as legal counsel to HSE.
- J-Power USAcoreHull Street Energy agreed to acquire four thermal power plants from J-Power USA (Edgewood Energy, Shoreham Energy, Pinelawn Power, and Equus Power I) on Long Island, NY, providing 300 MW of capacity. CIBC Capital Markets and Merit Capital Advisors acted as financial advisors and Baker McKenzie acted as legal counsel to J-Power USA. Upon closing, HSE affiliates own ~2,650 MW of gas-fired and dual-fueled generation in the Milepost Power fleet.
- Upstream TechcoreHull Street Energy made a strategic investment in Upstream Tech, whose products HydroForecast (next-generation global water forecast) and Lens (remote monitoring and reporting platform) are used in water/environmental applications. HSE views water and geoscientific forecasting as increasingly important for climate-related investing. Faegre Drinker Biddle & Reath acted as legal counsel to HSE; DLA Piper LLP acted as legal counsel to Upstream Tech.
- Energy Harbor Corp.coreETEM, an affiliate of HSE, completed a series of customized transactions with subsidiaries of Energy Harbor Corp. to facilitate Energy Harbor's divestiture of fossil-fueled electric generating assets and associated liabilities. ETEM acquired the W.H. Sammis Power Plant (2,220 MW, Ohio), Hollow Rock Landfill, and the Pleasants Power Plant (1,280 MW, West Virginia). ETEM expects to demolish, remediate, and repurpose the sites. Babst, Calland, Clements and Zomnir, P.C. was transactional counsel for ETEM.
- Atlas HoldingscoreHull Street Energy and Atlas Holdings signed a definitive agreement for HSE to acquire 100% of the Bastrop Energy Center and Paris Energy Center (855 MW combined) in Texas from Mesquite Generation Holdings LLC, an affiliate of Atlas. King and Spalding and Houlihan Lokey acted as legal counsel and financial adviser to Atlas.
- SunGrid SolutionscoreHull Street Energy made a substantial capital commitment to SunGrid Solutions, a leading BESS services company using its proprietary PowerPlay and SimpleOS platforms for Turnkey and Balance of Plant EPC and integrated BESS enclosure systems. SunGrid has deployed more than 500 MWh of battery storage throughout the US and Canada. Javelin Capital acted as financial advisor; The Law Office of Jon Staley, Margie Strub Construction Law LLP and Renno & Co. Inc. acted as legal counsel to SunGrid; Faegre Drinker Biddle & Reath LLP and Goodmans LLP acted as legal counsel to HSE.
- ENGIE North AmericacoreHull Street Energy acquired 100% of the Waterbury Generation facility (96 MW flexible, fast start natural gas plant) in Waterbury, Connecticut, from a subsidiary of ENGIE North America. Troutman Pepper LLP acted as legal counsel to HSE.
- Foundation Solar PartnerscoreHull Street Energy acquired the management team and development pipeline of Foundation Solar Partners, an independent solar development company that develops utility-scale solar projects in the eastern US (PJM transmission territory). FSP has developed and sold 1 GW of solar projects. Baker Botts LLP acted as legal counsel to Hull Street Energy and The Law Office of Jon Staley acted as legal counsel to Foundation Solar Partners. FSP was later divested by HSE in March 2023.
- EGPNA Renewable Energy Partners (Enel Green Power North America / GE Energy Financial Services)coreHull Street Energy signed an agreement to acquire 31 hydroelectric facilities with 255 MW of capacity from EGPNA Renewable Energy Partners, a joint venture between Enel Green Power North America and GE Energy Financial Services. The plants supply reliable, low-carbon energy in Vermont, Washington, Massachusetts, New York, Virginia, South Carolina, Idaho, California, North Carolina, West Virginia and Pennsylvania. BNP Paribas Securities Corp. served as sole placement agent and ancillary facility provider on a private placement financing; Baker Botts LLP acted as legal counsel to HSE.
- EversourcecoreHull Street Energy agreed to purchase nine hydroelectric power facilities in New Hampshire (68.2 MW) from Eversource for $83 million. The plants are located in Manchester, Bristol, West Stewartstown, Franklin, Bow, Gorham, Hooksett, Hillsborough and Berlin, NH. Manatt Phelps and Phillips, LLP and Hogan Lovells acted as legal counsel to HSE.
- Greenskies Clean FocuscoreGreenskies Clean Focus is one of HSE's portfolio companies, offering a full suite of decarbonization solutions including onsite and offsite solar, battery storage, microgrids, and CCHP. Clean Focus finances and owns the systems while Greenskies originates, develops, constructs, and operates.
- Flatiron EnergycoreFlatiron Energy is a certified B Corp and HSE portfolio company that develops, owns, and operates large-scale battery storage infrastructure, including a 4.5 GW portfolio of utility-scale BESS assets in the Northeast US (e.g., Taft Project in Massachusetts). HPS Investment Partners provides the $250 million corporate credit facility; Hull Street Energy provides equity commitments.
- TruGridcoreTruGrid is a premier utility-scale EPC and O&M contractor for BESS and solar, based in Houston, Texas, and owned by Hull Street Energy. TruGrid specializes in battery integration technology and turnkey project delivery and was the recipient of the National Safety Council Perfect Record Award in 2025.
- Energy Transition and Environmental Management LLC (ETEM)coreETEM is a Texas-based energy transition and liability transfer company and HSE affiliate. ETEM acquires, remediates, and repurposes fossil-fired electric generation, offering a full and final transfer of risks and liabilities associated with retired and operating generation. Notable transactions include the W.H. Sammis Power Plant and Pleasants Power Plant.
- Serium Energy StoragecoreSerium Energy Storage is an HSE portfolio company pioneering the use of underground, closed-loop, pumped storage to help meet global decarbonization goals.
- Confluence HydrocoreConfluence Hydro is a wholly owned subsidiary of HSE formed to own and manage Consumers Energy's 13 Michigan hydroelectric dams (132 MW) and future hydro acquisitions. Confluence Hydro entered a 30-year power contract with Consumers Energy and plans to seek approval to renew the dams' federal operating licenses.
- Milepost Power HoldingsflagshipMilepost Power Holdings is HSE's thermal power infrastructure business unit, established in 2017 with the Maxim Power (USA) acquisition. It owns and operates ~3.6 GW of natural gas fired combined cycle, simple cycle and reciprocating engine power plants in Texas, California, New York, Massachusetts, Connecticut, New Jersey, and Illinois, providing critical reliability service to the electricity grid.
Scale indicators13 records
Recent moves13 records
Expansion highlights6 records
Hull Street Energy competitors and assessment
Company assessmentDirect peers
- Energy Capital Partners: Energy Capital Partners is a direct peer — a private equity firm focused on power generation, midstream energy, and energy transition. ECP is comparable in scale, sector focus, and transaction style, competing with HSE for utility and IPP divestitures and operating an integrated platform across multiple power subsectors.
- LS Power: LS Power is a direct peer — a private equity and infrastructure firm focused on power generation, transmission, and energy storage across North America. LS Power is a direct comparable as the buyer of HSE's Central Rivers Power hydro portfolio and operates in the same middle-market power deal space with similar thermal, hydro, and storage strategies.
- ArcLight Capital Partners: ArcLight is a direct peer — a private equity firm focused on energy infrastructure and power generation across North America. ArcLight sold Sunrise Power Holdings to HSE in 2023, and the two firms compete for the same mid-market power asset divestiture pipeline from utilities and IPPs.
- Antin Infrastructure Partners: Antin Infrastructure Partners is a direct peer — a European-listed infrastructure and private equity firm with a significant North American power generation focus. Antin targets the same middle-market power and energy transition opportunities as HSE with comparable fund sizes and platform-oriented strategies.
- Rockland Capital: Rockland Capital is a direct peer — a private equity firm focused on control investments in critical power generation assets in the U.S. and U.K. Rockland is currently a counterparty to HSE (selling 1.3 GW of PJM peaking capacity) and competes for the same fleet of mid-market thermal generation assets.
Broad incumbents
- Brookfield Renewable: Brookfield Renewable is a broad incumbent — one of the world's largest publicly listed owners of renewable and hydroelectric assets, with a major North American hydropower portfolio. Brookfield competes with HSE's hydro and storage platform and has been a direct counterparty in similar transactions.
- BlackRock Real Assets: BlackRock Real Assets is a broad incumbent — a global infrastructure and power investor that has been a direct counterparty to HSE (selling Crockett Cogeneration). BlackRock competes for the same middle-market power deals as part of a much broader real assets platform with significantly more capital and resources.
- Macquarie Asset Management: Macquarie Asset Management is a broad incumbent — one of the largest infrastructure investors globally, with a major North American power generation business. Macquarie competes with HSE in the same power asset universe but at meaningfully larger scale, broader asset class coverage, and from a publicly listed parent.
Others
- Constellation Energy: Constellation Energy is an adjacent major — a publicly listed integrated power company and former parent of several HSE senior team members. Constellation is relevant contextually as a talent origin and potential counterparty but does not directly compete as a PE buyer of mid-market power assets.
Emerging players
- Generate Capital: Generate Capital is an emerging player — a sustainable infrastructure financier focused on distributed energy, BESS, microgrids, and decarbonization. Generate is a partial comparable given its focus on the storage and behind-the-meter side of HSE's Flatiron, TruGrid, and Greenskies portfolio, though with a smaller and more distributed approach.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat6 records
Key risks7 records
Key highlights7 records
Customer concentration
Hull Street Energy social profiles
Digital presenceHull Street Energy compliance and trust
Trust signalCompliance1 record
Hull Street Energy financial estimates
Financial estimateRevenue estimate
Valuation estimate
Hull Street Energy leadership team
Management profileNumber of profiles
Profiles6 records
Hull Street Energy subsidiaries and ownership
Company hierarchySubsidiaries12 records
Hull Street Energy funding detail
Funding detailFunding overview
Funding rounds
Investors
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Hull Street Energy M&A and investment
M&A and investmentM&A6 records
Investments5 records
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Hull Street Energy
What does Hull Street Energy do?
Hull Street Energy is a private equity firm that makes controlling equity investments in middle market power businesses in North America, deploying capital into the power sector as it decarbonizes. The firm owns and operates a portfolio of renewable, gas-fired, and energy storage generation assets through subsidiaries such as Milepost Power, Confluence Hydro, and Flatiron Energy, and provides utility-scale EPC services through TruGrid and SunGrid Solutions. HSE has raised over $5.0 billion in equity and debt capital across three institutional funds and currently manages approximately $4.6 billion in AUM.
Is Hull Street Energy a public or private company?
Hull Street Energy is a private company. It is classified as founder individual operated bootstrapped and is currently operating.
When was Hull Street Energy founded?
Hull Street Energy was founded in 2014. It employs 11 to 50 people.
Where is Hull Street Energy based?
Hull Street Energy is headquartered in Bethesda, United States, in the North America region.
How does Hull Street Energy make money?
Four revenue lines are on record. Private equity fund management fees and carried interest is the primary driver. The others are power generation and storage asset revenue (through portfolio companies), EPC, O&M and construction services (through TruGrid and SunGrid) and asset dispositions / investment realizations.
Who are Hull Street Energy's main competitors?
Direct peers on record are Energy Capital Partners, LS Power, ArcLight Capital Partners, Antin Infrastructure Partners and Rockland Capital. Broad incumbents are Brookfield Renewable, BlackRock Real Assets and Macquarie Asset Management. Constellation Energy is listed as an others. Generate Capital is listed as an emerging player.
Does Hull Street Energy have an API?
No public API is recorded for Hull Street Energy.
What industry is Hull Street Energy in?
Hull Street Energy's product category is Power Sector Private Equity. Its primary akta.pro industry code is FSANAEAB, Energy & Power Infrastructure Funds (Generation, Transmission, Storage), with a secondary code of FSAAAKAG, Renewable Energy Infrastructure.