PRO-DAIRY Releases Anaerobic Digester Fact Sheets for Farmers

By Lauren Ray

Considerations for central systems of dairy manure anaerobic digestion to renewable natural gas

A newly released fact sheet by Angela George, Jason Oliver, and Lauren Ray, PRO-DAIRY Dairy Environmental Systems, gives an overview of three configurations of centralized systems for anaerobic digestion to renewable natural gas (RNG) that involve multiple dairy farms to achieve economy of scale. Key considerations and questions for discussion among participating dairy farms and the project developer for these systems are included.

PRO-DAIRY Dairy Environmental Systems also released fact sheets on planning for a centralized AD system or central biogas upgrading system for multiple farms. Anaerobic digestion (AD) of dairy manure to produce renewable natural gas (RNG) requires large-scale to be economically viable. Centralized manure AD-to-RNG systems can enable dairy farms of all sizes to collectively participate, including those who may not have the capital or land resources to build and operate their own AD system. One possible arrangement is to feed a single AD system with manure from multiple farms and upgrade biogas to RNG at the AD site. Another possible arrangement is to use a central biogas upgrading skid to upgrade biogas from multiple farms. This allows multiple farms with their own AD systems to convert biogas to RNG by sharing the cost of the upgrading equipment and pipeline insertion point.