Who we are

ArcLight is a leading middle market, value added, infrastructure investment firm focused on sustainable infrastructure.

Founded in 2001, we have over two decades of experience owning and operating infrastructure investments across the entire value chain, from the turbine to wall socket.


With the world driving toward a sustainable infrastructure future, ArcLight believes that a fundamentals-driven, real asset investment strategy, in support of decarbonization, accessibility, affordability, and reliability, is as important as ever.  ArcLight believes these imperatives will likely drive ~$50 trillion of capital investment requirements over the next two decades and that the solution to a sustainable infrastructure future rests in a well thought-out and managed transition.


We believe that this transition will likely create a highly attractive investment environment for experienced and skilled investors capable of identifying and assessing the most attractive opportunities, spanning both responsibly-managed, critical incumbent infrastructure and, selectively, new infrastructure deployments.


Our approach has led to over $27 billion invested across 125 transactions with 83 exits.

Firm history

ArcLight Founded.

First investment in geothermal power generation.

ArcLight Energy Partners Fund I closes with $950 million in commitments.

First investment in wind power generation assets.

ArcLight Energy Partners Fund II closes with $1.6 billion in commitments.

First hydropower investment.

ArcLight Energy Partners Fund III closes with $2.0 billion in commitments.

Significant investment in over 700 MWs of wind, solar and geothermal power projects.

ArcLight Energy Partners Fund IV closes with $2.1 billion in commitments.

Forms CAMS affiliate providing specialized operations, maintenance and asset manage capabilities. Today, CAMS continues to be an important operation partner to ArcLight.

Forms ArcLight Market Analytics, an in-house quantitative data analytics, fundamental market research, regulatory and risk management.

Forms ArcLight Project and Risk Management, to provide capital project diligence, budgeting, management, execution and risk management.

ArcLight Energy Partners Fund V closes with $3.3 billion in commitments.

Formal adoption of ESG investment guidelines.

ArcLight Energy Partners Fund VI closes with $5.6 billion in commitments.

Inaugural ESG policy and cross-functional ESG team established.

ArcLight Energy Partners Fund VII closes with $3.4 billion in commitments.

ArcLight Clean Transition Corporation invests in electric vehicle technology manufacturer - Proterra.

Investment in advanced mobility platform - Inspiration Mobility.

ArcLight becomes a signatory to UN PRI.

ArcLight Renewable Infrastructure Fund I closes with $200 million in commitments.

ArcLight enhances integrated and data driven ESG policy and procedures.

ArcLight Clean Transition Corporation II invests in renewable natural gas solutions platform - Opal Fuels.

Forms ArcLight Development Services, to provide strategic oversight of renewables, battery storage assets and brownfield development projects.

ArcLight closes Third Coast Midstream Continuation Vehicle.














ESG executive summary

We have embraced ESG and apply ESG principles rigorously in our investment process.

Our approach to ESG is measured and includes formalized ESG diligence results for new investments, the collection of KPI data, as well as data on good governance, DEI, and the tracking of carbon emissions and other environmental impacts of our investments. These initiatives are additionally supported by our memberships in UN PRI and NICSA Diversity Project North America.

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Corporate Social Responsibility

We believe in making a positive impact in our own communities. As part of that effort, both ArcLight and our employees provide time and capital to these important organizations:

Find the Cause Breast Cancer Foundation is on a mission to fund research into the environmental causes of breast cancer and educate the public about its prevention.

Pine Street Inn helps Boston’s homeless people move from the streets and shelter into a home, and formerly homeless people to retain their housing, though street outreach, emergency services, supportive housing, job training and employment connections.

Read-to-a-Child believes every child deserves to have a caring adult read to them, and partners with community and corporate volunteers to make that happen. Readers share stories one-on-one with elementary students from under-resourced schools in Boston, Detroit, Hartford, Los Angeles and Miami.

The American Heart Association funds cardiovascular research, promotes healthy living and fosters cardiac care to reduce disability and deaths from cardiovascular disease and stroke.

Volunteer Match connects people offering time or service with opportunities to do good in the community all over the world.

Foundation for MetroWest improves the quality of life in more than 30 MetroWest communities by providing financial and educational resources to local nonprofit organizations. It shares essential data about the region to inform decision making, and partners with donors to help align their giving with the areas of greatest need in the community.

Team IMPACT matches children facing serious illness and disability with college sports teams. Its goal is to guide children and teams in a mutually beneficial relationship of belonging, empowerment, and resilience, creating a long-term, life-changing experience for everyone involved.

The ESCALA Initiative provides women and other marginalized groups with access to business education and other forms of support. By helping people become profitable and self-sufficient entrepreneurs, ESCALA enables them to raise living standards for themselves and their communities.

Under the Same Sky raises awareness and funding for areas requiring suicide awareness and survivor support. It promotes education, awareness, and advocacy for those affected by suicide.

JDRF finances research devoted to curing, preventing, and treating type 1 diabetes (T1D). It advocates for government support of research and new therapies, ensures new therapies come to market and are recommended by healthcare providers, and helps connect and educate members of the T1D community.

Little Brothers Friends of the Elderly Boston’s goal is to prevent and relieve isolation and loneliness among older adults. It connects residents of affordable and public housing with local college students to encourage the formation of intergenerational friendships, organizing weekly social, educational, creative, and technology programs.