USING ENERGY SAVINGS TO PAY FOR NEW/UPGRADED EQUIPMENT AND IMPROVED RELIABILITY

摘要

In 1996, Planergy Services, Inc. approached the Chevron refinery at Richmond, CA where I was then the Energy Efficiency Coordinator. Planergy had won a public bid with Pacific Gas & Electric to provide industrial energy efficiency services, under a program sponsored by the California Public Utilities Commission. Planergy had contracted to provide 23 million kW hours a year in energy savings, for which they would be paid, based on measured and verified savings. The California Energy Commission hoped that under such programs the State would be able to save 70% of the expected demand growth of 10,000 Megawatts that California was forecasting over a 10-year period. The technology Planergy had initially chosen to achieve these savings was variable frequency drives. This technology, which did not have wide application in refinery process at the time, basically uses changes in frequency and voltage to change the speed of electric motors. Pumps, compressors, or fans are being driven by the electric motors, and flow of liquids or gases into the process are then regulated by changes in machine speed, rather than by valves or dampers. The theory was that not only would there be large energy savings, but the rotating equipment's reliability would be improved since it no longer would be run at constant speed, with mechanical valves or dampers choking off the flow. The Chevron Chemical plant adjacent to our refinery had previously installed a variable frequency drive on a 1,000HP pump, so there was some operating experience the refinery could draw on internally to evaluate drive performance. This experience was judged to be satisfactory, so we began to evaluate the use of drives in refinery applications.