IMPACTASSETS 50™
An Annual Showcase of Impact Investment Fund Managers
ImpactAssets 50
An Annual Showcase of Impact Investment Fund Managers
Lime Rock New Energy, L.P.

Climate Change
Diversity, Equity and Inclusion
Workforce Development, Upskilling and RetrainingFirm Overview
Lime Rock New Energy is exclusively focused on investing in companies that help their customers produce or consume energy with a measurable, positive environmental impact. We are focused on companies that provide products and services for renewable generation and grid modernization, energy efficiency for industry and the built environment, and the decarbonization of transportation. By bringing our dedicated energy transition focus, deep industry and operating expertise, and true value-added partnership, we aim to help innovative companies active in the new energy economy grow profits, operations, and market share. We at LRNE view it as our mission to contribute to climate solutions through the smart and effective deployment of capital, and by actively supporting those companies in which we invest. LRNE believes that our approach to investing in and supporting companies that are delivering lower/no carbon products and services contributes to slowing and/or mitigating the impact of climate change.
Years of Operation: 3 – 4 years
% of Capital from Top 3 Investors: 25% – 49%
Lime Rock New Energy looks to provide true growth equity capital and industry operating expertise to high-growth entrepreneurial companies that deliver proven, commercial products and services that help their customers produce or consume energy with a material and quantifiable reduction in GHG emissions.
Lime Rock New Energy believes that the need and demand for climate-positive products and services is accelerating, but that the capital necessary to decarbonize our global economy remains far short. This is where LRNE looks to make a difference. Companies in which we invest are delivering products and services that have a meaningful impact on decarbonizing the economy and creating a more sustainable planet combined with compelling economics to help drive their adoption and use. At LRNE we bring to these companies not just capital but also deep operating, financial, impact, and policy expertise to help entrepreneurs accelerate the growth – and impact – of their businesses. In short, everything we do at LRNE is focused on bringing catalytic capital to businesses that are delivering real, measurable positive climate impacts while delivering market rate returns to our investors.
LRNE differentiates itself by bringing much more than capital to companies. The founders of LRNE came together to purpose-build an investment team and advisory board with experience in energy transition investing, C-level operating leadership, technology development and adoption, energy policy, and finance. Critically, we bring deep operating and technical expertise and experience, and broad networks of potential customers, suppliers, financial institutions, and policy leaders that are immensely valuable to our companies. We have worked with each of our portfolio companies to introduce new customers, supply chain partners, and financing providers. LRNE also attributes high value to the impact measurement and management of our portfolio companies. We work with each portfolio company to develop a comprehensive framework and pathways for measuring our key impact KPI, avoided CO₂ equivalent emissions. We also help companies to quantify their overall avoided emissions through our Carbon Enterprise Value (CEV) concept.
Investment Example
In September 2023 LRNE invested in Power TakeOff, an industry leader in the delivery of high-impact, virtually delivered energy efficiency solutions for the hard-to-reach small and medium business (SMB) market. Power TakeOff uses advanced AI and ML analytics to distill vast quantities of utility smart meter data into customized energy efficiency actions for SMBs via the implementation of improved building management systems set points. By working with SMBs to simply adjust the settings on their BMS, Power TakeOff delivers energy savings on average of 18% annually. Just this year leading utilities across North America will rely on Power TakeOff to help them deliver more than 60 gigawatt-hours of energy savings, all of which reduce GHG emissions. Power TakeOff also partners with utilities to target energy savings specifically within disadvantaged communities, thus providing cost and energy savings to communities that have historically suffered from a lack of energy equity.
Leadership and Team
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Mark J Lewis – Managing Director More Info
Mark Lewis is a Managing Director with responsibility for investment sourcing, execution, and overall fund management. He currently serves on the boards of directors of Electric Power Engineers and Power TakeOff, and is a board observer at Aperia Technologies. Mark joined Lime Rock New Energy in 2018 and brings to this role a career in clean and renewable energy portfolio company management and operations, energy transition investing, and strategic energy technology acquisitions. Prior to joining LRNE, Mark served as President of TAE Technologies, Inc., a leading fusion energy technology development company. |
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Mark McCall – Managing Director More Info
Mark McCall is a Managing Director with responsibility for deal sourcing, execution, and overall fund management. Mark was appointed by President Obama to serve as the Executive Director of the Loan Programs Office at the U.S. Department of Energy from 2015 to 2017. In that capacity, he reported directly to the Secretary of Energy and was responsible for a $30 billion portfolio of existing clean energy technology investments, as well as originating new loans for four loan programs designed to support the commercialization of innovative technologies that reduce greenhouse gas emissions in the automotive, nuclear, hydrocarbons and renewables industries. |
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Blair Barlow – Managing Director More Info
Blair Barlow joined the Lime Rock New Energy team in 2021 as a Director and is now a Managing Director. Prior to joining Lime Rock New Energy, Blair spent 13 years on the Lime Rock Partners team where he gained increasing deal management responsibilities, rising from the level of Associate. He brings to the team diverse deal selection, execution, and portfolio company strategic execution experience and has played a leadership role in global field service, product, and technology-oriented companies in the Lime Rock Partners portfolio. |
Financial Performance
Impact Performance
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Percentage of Total Assets Under
Management that are Impact Investments: |
100%
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Our investment identification and sourcing process, due diligence, and post-investment management processes are all centered around ensuring that the capital that we deploy delivers material impact, principally in the form of GHG/CO2 emissions abatement via the use of the products or services of the businesses in which we invest. We also identify and report on impact pathways such as job creation, diversity, equity and inclusion, waste reduction, etc. as part of our investment process. We work with each of our portfolio companies to baseline their business when we invest and develop, in conjunction with management, actions to improve the impact of our companies. We also incorporate impact considerations into our analysis when we exit our investments. In order for LRNE to consider an investment, a company must also contribute in a tangible way to at least one of the United Nations Sustainable Development Goals.
As part of diligence, LRNE has management complete a comprehensive ESG and impact due diligence questionnaire to ensure the company’s processes are robust, and to identify deficiencies, if any. This information is used to develop mitigation/improvement plans and strategies that address any deficiencies should we ultimately choose to invest in the business. LRNE has also developed a model ESG policy for our portfolio companies, which is refined and customized by each portfolio company before being implemented.
Impact Tracking and Monitoring
Learn More
274 Riverside Ave., Westport, Connecticut 06880 USA
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