The Spokane Regional Solid Waste System is considering a $1.25 million upgrade to the Waste to Energy Facility that would enhance its electrical generating efficiency by about a megawatt, or enough electricity to power 500 homes.


The Spokane City Council, which operates the regional solid-waste system in a joint project with Spokane County, already has approved the expenditure. The Spokane County Commission must also give its OK, and is expected to consider the issue later this month.


Dennis Hein, solid waste director for the city, says the upgrade would involve replacing the trash-burning plants constant-speed motors with more-efficient ones, thus reducing the amount of power the plant consumes for operations, leaving more electricity available to sell.


Because of plant fluctuations, the facility currently generates between 12 and 21 megawatts, Hein says. However, it uses 3.4 megawatts of energy in the production of that generation. Hopefully, the use of adjustable-frequency drives will substantially cut the amount of energy necessary for electrical generation.


A total of 14 high-voltage, constant-speed pumps, fans, and compressors will be replaced.


Hein says the conversion is expected to boost the plants power production by more than 9 million kilowatt-hours per year. The sale of that power would bring in an additional $757,000 annually for the Spokane Regional Solid Waste System and $46,000 for Wheelabrator Spokane Inc., he says. The expected payback period is between 20 and 24 months.


Wheelabrator, which manages the operation of the facility, has agreed to conduct the conversion for a fixed price.