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Biodiesel Fueled Engine Generator with Heat Recovery

The Biodiesel Engine-Generator with Heat Recovery provides electricity for the IW as well as thermal energy for the steam absorption chiller and regeneration energy for the ventilation unit during the summer and hot water via the steam-hot water converter for the radiant units and the fan coils in the winter.

The process of developing this project involved developing a preliminary flow diagram with mass and energy balances to size each piece of equipment. Next a detailed flow diagram was developed with an engineering firm, which led to an equipment layout.

The engine-generator has a maximum electrical output of 25 kW and can generate 20 kW of steam via a steam generator and 20 kW of hot water via a coolant heat exchanger.

The preliminary layout and flow diagrams were sent out to bid for installation and the contract was awarded to Wayne Crouse of Pittsburgh, PA. Installation began on April 5, 2007 and was completed on August 31, 2007.  The preparation of the space, installation of the equipment, controls and instrumentation is detailed in a construction log which is updated frequently.

Startup began on September 4, 2007 with the engine-generator in a stand alone mode. Next, the engine-generator was paralleled to the utility via the transfer switch, which was finished on April 7th, 2007. Heat recovery startup began on October 24, 2007 and was completed on the 25th. 

Commissioning has been conducted on each major piece of equipment to verify installation and manufacturer’s specifications. The major pieces of equipment performed as predicted based on manufacturer's specifications. However, as the engine generator operates at approximately 80% of its maximum rating, the heat outputs are lower than the manufacturer's specifications, which show operation at 100% of the engine's rating. This has led to longer heat up times, and slight short falls on heat availability. 

Experiments are being conducted to determine how well various types of biodiesel fuel work in this engine and how well the system performs in the heating and cooling season. Additional experiments include emissions testing and engine optimization. Click results for experimental results.


Fred Betz – PhD. candidate

Brian Goodwin - Intern