The story
1984–1999
In 1984, Calpine was founded in Silicon Valley, California. Peter Cartwright and four of his co-workers, the Guy F. Atkinson Construction Company of South San Francisco, and the Electrowatt Corporation struck an investment arrangement. With initial capital of US$1 million, it was essentially a Silicon Valley startup company. In 1988, the first QF cogeneration plant was commissioned and power production began.
The name "Calpine" is derived from the company's original California location and alpine, a reference to the Zürich home base of Electrowatt. Electrowatt provided essential assistance when Calpine was a startup.
In 1988, the first QF cogeneration plant was commissioned and power production began. In 1992, the company's assets reached US$21 billion. In 1994, the company reached capacity output of 141 MegaWatts. In 1996, the company's initial public offering was the largest for an independent energy company.
In 1999, Calpine bought PG&E's holdings at The Geysers, acquiring most of the geothermal complex. The Houston-based company operates 15 plants and produces about 725 megawatts.
2000–2020
In 2001, the California electric energy crisis occurred. In 2004, the investment bank Lehman Brothers begins shorting Calpine, with researcher Christine Daley lacking confidence in Calpine. This information spreads to clients of Lehman. By the time Calpine goes bankrupt in 2005, Lehman will profit roughly $100,000,000 from the short. In November 2005, CEO Peter Cartwright and CFO Bob Kelly resigned.
In 2004, Calpine purchased the Brazos Valley Power Plant in Texas for $175 million. At the time of sale, the natural gas combined cycle plant had a capacity of 570 megawatts.
In 2005, the founder and CEO of Calpine, Peter Cartwright, resigned amid severe financial problems for the company. Kenneth T. Derr was named acting CEO. Derr was a retired Chevron executive.
On January 31, 2008, Calpine emerged from bankruptcy protection. The company's previous stock was exchanged for warrants and new Calpine stock began trading on the NYSE under the ticker symbol "CPN." Later that year, a new management team, headed by president and CEO Jack Fusco, joined the company.
Read the full text
In 2010, Calpine bought the Conectiv Energy power plant fleet from Pepco for $1.65 billion. The deal included 18 operating plants and one plant that was under construction. The Conectiv acquisition provided access to markets in the Northeast.
In 2016, Calpine acquired Noble American Energy Solutions from Noble Group. Calpine paid roughly $800 million with an additional amount of roughly $100 million in net working capital paid at closing. The acquisition was funded with cash-on-hand and a one-year loan of about $550 million. The name of this business unit was changed to Calpine Energy Solutions.
In 2018, Calpine was acquired by an affiliate of Energy Capital Partners and a consortium of other investors including Access Industries and the Canada Pension Investment Board. A new board was appointed shortly after the acquisition. As Calpine became a private company its stock stopped trading prior to the opening of the New York Stock Exchange on March 9, 2018.
In 2019, Calpine sold its RockGen plant in Wisconsin to Starwood Energy.
2021–present
In February 2023, Calpine released plans to begin development for a 425 MW natural gas-fired plant next to the Freestone Energy Center in Freestone County, Texas.
In July 2023, Calpine announced a $25 million carbon capture technology project. The technology could capture 95% of a plant’s carbon emissions, which would reduce greenhouse emissions. The technology was created by ION Clean Energy of Colorado.
In January 2025, Constellation Energy agreed to acquire Calpine for $16.4 billion ($26.6bn including debt) in a cash-and-stock deal. Exactly one year later, Constellation announced that it had completed the transaction.
In April 2025, ExxonMobil announced that it had reached an agreement with Calpine to carry away and store up to 2 million metric tons of carbon dioxide per year from Calpine's Baytown Energy Center near Houston. This agreement is part of a larger carbon capture and storage project at this site.
From Wikipedia’s article on Calpine, shared under CC BY-SA 4.0.4