- Apr 05, 2012
Stuart H. Russell, P.E., V.P. of perations, presented “Enhancing Biogas Project Economics Utilizing Blending and Storage Technologies” at the International Biomass Conference April 18, 2012 in Denver, CO.
Biogas project economics depend upon maximizing the use of the biogas resource to generate project revenue (or savings) to offset development, construction and operating costs. Many biogas facilities utilizing digesters have variable biogas outputs that depend upon the characteristics of the digested organic materials and operating conditions of the digester (internal biochemistry, temperature, pH, etc.). Biogas flow and calorific value (CV) can vary significantly over time.
Utilizing all of the available biogas under such variable biogas conditions can be a challenge. Biogas combustion equipment (engines, boilers, etc.) is typically sized for average flow and CV conditions. When the biogas conditions are either higher than the combustion equipment can consume, or lower than the turn-down capacity of the combustion equipment, the biogas must be flared – therefore generating no economic benefit.
This presentation described approaches to maximizing the combustion of biogas under variable conditions utilizing gas blending and storage technologies. Blending technologies blend the biogas with a conventional fuel such as Natural Gas or LPG to enhance CV, or correct for low-flow conditions. Biogas storage technologies allow the biogas to be stored during peak generation periods, then drawn down for combustion during low-flow periods. The conditions under which these technologies may enhance project economics were presented.
The conference was attended by several hundred professionals in the biogas, biomass energy and alternative fuels industry.