Press Release
August 25, 2021

Funds Managed by Affiliates of Apollo Global Management Announce $150 Million Equity Commitment to FlexGen Power Systems, Inc.

Large Investment in Energy Storage Integrator Demonstrates Apollo's Support for Growing FlexGen's Market Leading Energy Storage Capabilities

DURHAM, N.C. and NEW YORK, Aug. 25, 2021 /PRNewswire/ -- Funds (the "Apollo Funds") managed by affiliates of Apollo Global Management, Inc. (together with its consolidated subsidiaries, "Apollo") (NYSE:APO) today announced a $150 million equity commitment to FlexGen Power Systems, Inc. ("FlexGen", or the "Company"), a leading integration services and software technology provider for energy storage solutions in the US and globally. Apollo's investment will be made in partnership with FlexGen's existing investors, Altira Group and the founding investment group led by Jerry Miller and Mark Dreyfus.

Energy storage represents a multibillion-dollar market at the center of the energy transition. The integration of energy storage requires software and technological solutions that play a critical role in the adoption of renewables at scale—offsetting the intermittency and reliability challenges that renewable power generation creates for the grid. Since its founding in 2009, FlexGen has supported deployments of more than 1.2 GWh of energy storage systems across the U.S. and internationally for utility, microgrid, and C&I customers. The Company's proprietary software platform allows energy storage owners to deploy various power market strategies and combine storage solutions with any form of generation.

Kelcy Pegler, Jr., CEO of FlexGen, commented, "Our work with Apollo will accelerate FlexGen's growth, and the capabilities we can offer going forward while establishing the bankability that the market values when making energy storage investments. We are well-positioned at the most critical intersection of the clean energy transition—energy storage. We have spent the past decade building the most advanced integration solutions in the market—and now that market is ready to take-off. I'm excited to have Olivia and the rest of the Apollo team's support in building on FlexGen's mission to deliver utility-scale storage that drives forward the clean energy transition."

Olivia Wassenaar, Senior Partner and Co-Lead of Natural Resources at Apollo, said, "Energy storage assets play a crucial role in the transition to an economy powered by intermittent renewable energy sources. This transition to renewable power is happening at a time where reliability and resiliency are more important than ever for the grid in the face of increasing extreme weather events. FlexGen's energy storage solutions bridge the gap of reliability for the grid and help accelerate the adoption of renewables by shifting renewable power consumption to times when it is needed most. We are impressed with the business that the entire FlexGen team has built and see continued tailwinds for the Company as the industry evolves."

Apollo Partner Trevor Mills added, "We are excited to work with Kelcy, Yann, Pasi, Alan, and the entire FlexGen team to support their continued growth. We see tremendous opportunities for growth and technological innovation in the energy storage sector as the grid relies increasingly on renewable energy. FlexGen's engineering expertise and leading HybridOS software solution position it as an ideal partner for those looking to develop and operate energy storage systems."

FlexGen is dedicated to providing best-in-class service and performance for its customers, seeking to ensure safety, reliability and resiliency in all operating environments. FlexGen supports the customer across the full journey of developing an energy storage project, and leverages decades of engineering and software expertise to maximize value that its customers ultimately receive. The company's HybridOS solutions include six distinct energy management solution applications including: DigitalTwin, FlexPack, SiteController, FleetManager, PowerCloud and FlexBidr. FlexGen's existing investors include Altira Group, the founding investor group led by Jerry Miller and Mark Dreyfus, Caterpillar Ventures, and GE Ventures.

The investment in FlexGen extends Apollo's track record of investing in and lending to companies supporting the clean energy transition. Over the past 18 months, Apollo Funds have invested in US Wind, an offshore wind developer; entered into a new venture with Johnson Controls to provide sustainability and energy efficiency services; formed a joint venture to accelerate the growth of renewables royalties company Great Bay Renewables; invested in electric-driven gas compression company TOPS; and agreed to invest in sustainable bioenergy producer AS Graanul Invest. The Apollo Fund-sponsored Spartan series of special purpose acquisition vehicles have announced or completed combinations with Fisker, an EV auto company; Sunlight Financial, a residential solar financing fintech, and most recently Allego, a leading pan-European EV charging company.

Vinson & Elkins LLP acted as legal counsel to the Apollo Funds. DLA Piper LLP acted as legal counsel and Citi acted as financial advisor to FlexGen.

About FlexGen Power Systems, Inc.

Based in Durham, N.C., FlexGen is a leading integration services and software technology provider for energy storage solutions in the United States and globally. FlexGen designs and integrates storage solutions and the software platform that is enabling today's energy transition. Leveraging its best-in-class energy management software and power electronics, FlexGen delivers utility-scale storage projects integrated with traditional and renewable power generation globally. Our clients and partners include the most technically and commercially demanding developers, utilities, government agencies and industrial companies in the world. To learn more, please visit

About Apollo Global Management, Inc.

Apollo is a high-growth, global alternative asset manager. We seek to provide our clients excess return at every point along the risk-reward spectrum from investment grade to private equity with a focus on three business strategies: yield, hybrid and opportunistic. Through our investment activity across our fully integrated platform, we serve the retirement income and financial return needs of our clients, and we offer innovative capital solutions to businesses. Our patient, creative, knowledgeable approach to investing aligns our clients, businesses we invest in, our employees and the communities we impact, to expand opportunity and achieve positive outcomes. As of June 30, 2021, Apollo had approximately $472 billion of assets under management. To learn more, please visit

About Altira Group

Altira Group is a Denver-based venture capital firm that works closely with entrepreneurs to scale emerging energy technology and software companies. Founded in 1996, Altira has invested over $1B with partners in over 60 companies. Its investment partners include a select group of oil and gas companies that help accelerate the growth of Altira's portfolio companies by serving as large, fast-adopting customers. The Altira team has over half a century of combined experience building successful technology companies. For more information, visit

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