Capstone Green Energy Corporation (CGRN)

Capstone Green Energy made microturbine power systems, compact gas turbines that generate electricity and heat on site for factories, hotels, oil fields and other users. Its products could run on natural gas, biogas and other fuels and were often used in combined heat and power setups. Over time the company also built a business renting turbines and providing long-term service contracts. It was based in Van Nuys, California.

The company was organized in 1988 as Capstone Turbine Corporation and went public on Nasdaq in June 2000 under the symbol CPST, during the dot-com era enthusiasm for distributed power. Despite its technology, it posted losses for most of its history and relied on repeated capital raises, with several reverse stock splits along the way. In April 2021 it renamed itself Capstone Green Energy Corporation and changed its ticker to CGRN to stress clean energy and energy-as-a-service.

In 2023 the company disclosed accounting problems that required restating earlier results and left it unable to file its annual report on time. Facing debt pressure, it filed a prepackaged Chapter 11 case on September 28, 2023. Nasdaq suspended trading on October 5, 2023, citing the bankruptcy, low market value, a sub-$1 share price and missed filings, and the delisting became final on October 23, 2023.

The reorganization plan took effect on December 7, 2023. A new holding company, Capstone Green Energy Holdings, took over the business and issued its shares pro rata to holders of the old common stock, trading over the counter as CGEH, while the old entity became a private subsidiary. In 2026 the successor renamed itself Capstone Energy+, Inc. and returned to Nasdaq under the symbol CEPL on July 8, 2026.