Powering Up with Centralized Biodigesters for Dairy Farms

By Kyle Beckman and David Weightman, California Energy Commission
December 7, 2012   |   3 Comments

California's dairy farms possess a valuable resource — manure — that can be turned into electricity, benefiting both farmers and the environment.

About 1,900 dairy farms dot the landscape in California, with millions of cows producing both milk and manure. The California Energy Commission wants to help milk that manure for all the power it can provide! In fact biodigesters, which produce gas from manure, offer a number of potential benefits: They generate energy, decrease greenhouse gases, reduce odors, improve water and air quality, and provide additional financial security for dairy farmers.

It is technically feasible to produce about 150 megawatts of generation (enough to power about 70,000 homes) from manure through the use of biodigesters, according to a study from the California Biomass Collaborative. The California Air Resources Board further estimates that the potential for methane capture from dairies amounts to about 3.1 million metric tons of carbon dioxide.

Savings and Revenue Opportunities from Community Digester Systems

Community digester systems not only provide useful power but also yield renewable energy certificates (RECs), carbon credits, and waste heat that can be used for multiple purposes. In some cases, the plants produce digested fiber that can be sold as bedding for cows, for composting, or for use by wholesale organic products companies. A summary of potential opportunities for cost savings and/or revenue generation is provided in Table 1 below.

Table 1. Summary of potential savings and revenue generation from community digester systems