Anaergia to build state-of-the-art co-digestion facility in California

Anaergia Inc., today announced it will provide technologies that will enable Monterey One Water, the wastewater utility of northern Monterey County, Calif., to make renewable energy from food waste as well as wastewater.

The project will significantly expand anaerobic digestion capacity at Monterey One Water’s Regional Treatment Plant (RTP) in Marina, Calif., and provide organic waste receiving and pre-processing equipment. This will allow the utility to receive and co-digest food waste in existing digesters currently used to process wastewater biosolids. When anaerobically digested, the waste produces renewable biogas, which is then used to generate electricity and heat at the Monterey One plant.

The project will return a mothballed anaerobic digester to service and provide state-of-the-art Anaergia digestion tank mixing technology to process food waste with biosolids without impacting critical wastewater operations. The new technology will simultaneously improve performance and save energy. Along with the ability to co-digest food waste with biosolids, Monterey One will benefit from a significant expansion of digester capacity to provide operational flexibility.

The project will increase biogas production from the plant’s four digesters by more than 150 per cent, which will be used to make up to 1.6 MW of renewable electricity via on-site combined heat and power (CHP) engines. The increased energy production will provide more than 100 per cent of the plant’s power needs, significantly reducing operating costs, supporting revenue generation, and increasing resiliency and reliability. This significant expansion in onsite energy generation is a major asset to the development of a joint microgrid that will be shared by Monterey One neighbour and regional solid waste agency, ReGen.

The upgraded anaerobic digestion technologies and new waste receiving equipment will assist the region’s solid waste industry, by enabling diversion of food waste from regional landfills to advance compliance with California’s SB1383 legislation. The new law is designed to reduce planet-warming methane emissions, which are created when food and other organic wastes are landfilled.

CalRecycle, California’ Department of Resources Recycling and Recovery, will provide $4,218,900 in grant funds, minimizing impact on the utility’s ratepayers by offsetting most of the project’s cost. Work on the project is expected to begin in Q2 2023 and be completed by Q3 2024.

“By upgrading its infrastructure to enable co-digestion of food waste along with its wastewater, Monterey One Water will now not only recycle water, it will also recycle organic waste that would have otherwise created methane emissions in landfills. This turns a big problem into a huge benefit and ultimately is what will make a net-zero future possible for planet earth,” said Andrew Benedek, chairman and CEO of Anaergia. “These proven technologies will eventually be implemented at hundreds of other wastewater treatment plants around the world, and Monterey One Water is leading the way.”

“With support from CalRecycle, we have a unique opportunity to co-digest wastewater solids with food waste to produce more green energy, which will both reduce our operating costs and cut our carbon emissions. This is a model solution for other wastewater utilities,” said Paul Sciuto, general manager of Monterey One Water.