Comparison of Internal Combustion Engines and Microturbines for Cogeneration at the Oceanside Water Pollution Control Plant, San Francisco, CA

Abstract

A biogas utilization study identified both internal combustion engines and microturbines as competitive alternatives for retrofit of the existing cogeneration system at the Oceanside Water Pollution Control Plant, San Francisco, California. To select a single preferred alternative to be carried forward into the conceptual design phase of the project, a multi-attribute evaluation of the alternatives was performed. Key criteria developed by the project team, force ranking of the criterion to establish weighting of the criteria, and detailed evaluation of the alternatives is presented. Ultimately, the internal combustion engine alternative was recommended, driven largely by the ability of the internal combustion engines to be able to more fully utilize the average and the maximum month biogas production at the Oceanside plant and physically fit within the existing facility. In addition, for this particular evaluation, the internal combustion engine alternative resulted in a higher net present value due to higher conversion efficiency of fuel to electrical power, while providing a higher product maturity ranking with equipment available from multiple equipment suppliers.

Environmental impact analysis of food waste anaerobic digestion and products utilization process

“…The biogas can be burned in an internal combustion engine or a micro-turbine. The power generation efficiency for internal combustion engine was set at 30% and meanwhile the recovery heat efficiency was set at 30% [12][13] (including cylinder liner heat and flue gas recovery heat). For plants with small capacities, microturbine, which have less restrictive fuel requirements than IC-engine, appear to be suitable for biogas use [14].…”