California Bioenergy (CalBio) is to install eight additional Mainspring Linear Generators at two of its dairy cluster biogas sites in California, bringing its total deployed capacity to 5.3 MW across five locations by the end of 2026.
The new units will be deployed at CalBio's North Visalia and South Tulare cluster biogas upgrading sites, each receiving a 1 MW installation.
The expansion builds on a partnership that began in 2022, when CalBio became the first dairy digester developer in the United States to deploy linear generators fuelled by dairy biogas, starting with a 1 MW installation at its Hanford cluster upgrader.
Subsequent deployments at Buttonwillow (1 MW) and a standalone digester project in Merced County (1.5 MW) have steadily grown the portfolio ahead of the latest addition.
CalBio's existing operations already deliver an annual greenhouse gas reduction of approximately 1.9 million metric tonnes of CO₂ equivalent — comparable to removing more than 430,000 petrol passenger vehicles from the road.
The company selected Mainspring's linear generator technology for a combination of attributes including fuel flexibility, fast-ramping capability and low emissions output.
The units produce fewer than 1.5 parts per million of NOx, meeting stringent air quality standards without requiring additional after-treatment systems — a significant consideration in California's tightly regulated air quality districts.
The expanded deployment is intended to strengthen energy resilience at rural dairy sites while generating an additional revenue stream for the family farms involved.
CalBio operates dairy digester clusters across California's Central Valley, aggregating biogas from multiple farms for upgrading and power generation.
CalBio expands linear generator capacity to 5.3 MW across California dairy biogas sites
