Sunnova has been acquired. And its former CEO has launched a new startup. Photo via sunnova.com

Solaris Assets has completed its acquisition of the majority of Sunnova Energy International’s residential solar assets. Houston-based Sunnova filed for Chapter 11 bankruptcy this summer after piling up billions of dollars in debt.

Meanwhile, Sunnova founder and former CEO John Berger has launched a Houston-based home energy services startup, Otovo USA, which just received more than $4 million in seed funding.

Solaris now owns Sunnova’s residential solar services platform and its solar generation and storage portfolio, along with leases, loans and power purchase agreements. Sunnova’s operations are being shifted to SunStrong Management, an Austin-based asset manager for the renewable energy sector.

“By bringing together SunStrong’s asset management expertise with Sunnova’s nationally scaled customer base, we are creating a stronger, more capable leader in the solar industry,” Brendon Merkley, CEO of SunStrong, said in a news release. “Our priority is to maintain the highest levels of service for customers as we expand our footprint as a premier solar asset servicer.”

In June, Sunnova sold its new-home business to homebuilder Lennar for $15.2 million and sold certain assets to investment firm Atlas SP Partners for $15 million.

As of December, Sunnova’s debt totaled nearly $10.7 billion, Reuters reported. Sunnova faced numerous challenges in its quest to survive, including higher interest rates, the reduction of solar incentives in California, and a shakeup in federal subsidies for renewable energy.

Sunnova filed for Chapter 11 bankruptcy in June. A month later, a bankruptcy judge approved the court-supervised sale of Sunnova. Solaris’ acquisition of Sunnova closed Sept. 3.

As SunStrong absorbs the bulk of Sunnova’s assets, Berger — who quit in March as Sunnova’s CEO — has formed a new business. He’s now the founder and CEO of Otovo USA, a partner of European residential power company Otovo.

Otovo USA offers solar power systems, solar batteries, standby generators, EV chargers, electric-load managers, and other power generation and management systems. Otovo’s AI-supported offerings are now available in Texas; the company plans to expand nationwide.

Otovo USA raised its seed funding from the EIC Rose Rock Venture Fund, which invests in energy startups.

“Otovo USA is here to help the millions of Americans with home energy services that are fed up with the complexities of warranties, juggling multiple vendors, and long repair times,” Berger said. The startup, he added, “is bringing customers what they really need: reliable power and a single partner accountable for keeping it up and running. It’s your power, backed by ours.”

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6+ must-attend Houston energy transition events for May 2026

Mark Your Calendars

Editor's note: May is starting off strong with two of the month's largest events beginning on Monday, May 4: Enverus Evolve Conference and OTC. Mark your calendars and begin registering now.

May 4-6, 2026 — Enverus Evolve Conference

Staying ahead of the curve in the energy sector is critical. This conference is designed to equip energy leaders with foresight in the energy market, providing cutting-edge technological know-how, sessions and networking opportunities industry leaders, and offering practical guidance on how to apply technology to solve big problems.

This event begins May 4 at Marriott Marquis, Downtown Houston. Register here.

May 4-7, 2026 — OTC 2026

The world’s largest offshore energy technology event returns to Houston beginning May 4. Dr. Mohamed Irfaan Ali, president of the Co-operative Republic of Guyana, will officially open the 2026 Offshore Technology Conference, delivering the Opening Address on May 4. This year's event will be cover the theme of "Steering Offshore Energy Innovation into the Future," emphasizes the pivotal role oil and gas, along with other emerging offshore energy sources, will play in shaping a sustainable and energy-secure future.

This event begins May 4 NRG Park. Register here.

May 14, 2026 — Gulf Coast ASSP Energy Corridor Section Meeting

At this lunchtime session, Chris Garza will speak on “Demystifying Regulatory Frameworks.” This session provides a comprehensive overview of key regulatory requirements concerning air quality, water discharge, and land management. Attendees will gain actionable insights into permits, reporting obligations, pollution prevention planning, and hazardous waste management. This session demystifies regulatory frameworks and empowers businesses to meet their legal responsibilities while promoting a culture of environmental stewardship. Attendees are welcome to stay for lunch and networking after the session.

This event takes place May 14 at 960 Memorial City Way. Register here.

May 16, 2026 — Energy Valuation Conference

ASA Houston's 16th annual EVC brings together energy valuation professionals and industry thought leaders to present timely educational valuation topics, with a focus on valuation impacts in the transition of power generation from fossil fuel to non-carbon, renewables, sustainable energy

This event takes place May 16 at The Briar Club, and there will be a live webcast. Register here.

May 18-19, 2026 — Geothermal Transition Summit North America

This two-day summit serves as the meeting point for the geothermal and oil and gas industries and will focus on geothermal energy, including scaling plants and navigating state regulations. The event promises 40 expert speakers, 15 exhibition spaces, and networking opportunities with 250 industry decision makers.

This event begins May 18 at Norris Conference Center. Register here.

May 20-21, 2026 — ESF North America

ESF North America returns for its 5th edition, under the theme of “innovation and adaptation.” Attendees will explore how technology, innovation, and collaboration can drive a resilient, competitive refining and chemicals industry.

This event begins May 20 at The Westin Oaks Houston at the Galleria. Register here.

Houston scientists unveil faster, low-energy method to recycle lithium-ion batteries

Battery breakthrough

Rice University researchers have uncovered a more energy-efficient and faster way to recycle critical minerals from used lithium-ion batteries.

Traditional methods rely on high heat, long processing times and harsh chemicals to recover a small fraction of critical materials from batteries used in everything from smartphones to electric vehicles. However, the team from Rice's Department of Materials Science and Nanoengineering developed a process that uses a water-based solution containing amino chlorides to extract more metals in less time

The team published the findings in a recent edition of the scientific journal Small.

Simon King, a sophomore studying chemical and biomolecular engineering who completed this work as a summer research fellow at the Rice Advanced Materials Institute, served as first author of the study. He worked with corresponding authors Pulickel Ajayan, the Benjamin M. and Mary Greenwood Anderson Professor of Engineering, and Sohini Bhattacharyya, a research scientist in Ajayan’s lab.

By using a hydroxylammonium chloride (HACI) solution, the team achieved roughly 65 percent extraction of key battery metals in just one minute at room temperature, according to the study. The efficiencies grew to roughly 75 percent for several metals under longer processing times.

“We were surprised by just how fast the reaction occurs, especially without the involvement of high temperatures,” King said in a news release. “Within the first minute, we’re already seeing the majority of the metal extraction take place.”

By not requiring high temperatures or long reaction times, Rice predicts the process could have a major impact on cost and the environmental impact of lithium battery recycling. Additionally, the water-based HACI solution makes waste handling easier and lowers certain environmental risks.

In addition to extracting the materials, the team went on to demonstrate that the recovered metals could be recycled and reprocessed into new battery materials.

“A big advantage of this system is that it works under relatively mild conditions,” Ajayan added in the release. “That opens the door to more sustainable and scalable recycling technologies.”