Cogeneration system and method

Abstract

A cogeneration system including a heat engine driving an electrical generator coupled to electrical lines at a site serviced by a utility is disclosed. The system includes supervisory means for monitoring the electrical energy and/or power supplied by the generator, supplied to the site by the utility, and consumed by site electrical loads, for storing monitored electrical data, and for controlling operation of the engine and generator in response to the monitored data. The system further is provided with data representing the energy and power rate structure of the local utility, and with a real time clock, and stores monitored electrical data and controls operation of the system in accordance with whether the time corresponds to a utility peak, intermediate, or off-peak energy rate period or to a peak demand measuring period. The system further comprises means for monitoring the thermal energy transferred from the engine to a site thermal load by heat exchange means. Also disclosed is circuitry for monitoring energy and power in electrical distribution lines and providing interlocking functions including means for multiplying voltage and current representative signals, a voltage-to-frequency converter for converting the product to a frequency signal, and a gated counter for integrating by counting the frequency signal over a predetermined time interval. Also disclosed is a multiple-unit cogenerator system each unit of which is provided with supervisory means as set forth above, one of which serves as a local area network master controlling communicating with the others over a local area network. One unit serves as a lead unit, varying its output to regulate the system output. Other units are turned full on or off as necessary to provide the desired output. Lead unit status is rotated among the various units of the system to equalize wear. A cogeneration method is disclosed including the functions of the apparatus set forth above.

Dependencies are inferred from the claim text.