Sometime this year, officials in Gresham, Ore. hope to be generating all of the 15,000 kWh needed to run the city’s wastewater treatment plant every day. An expanded fats, oils and grease (FOG) program and a solar photovoltaic array are expected to save the plant about $570,000 a year on its electric bill.Operated by Veolia Water NA, the plant serves the 119,000 people in Gresham and two nearby cities just east of Portland. The 20 mgd (design) activated sludge plant used a $40,000 grant from Oregon Economic and Community Development Department in 2010 for studying a FOG program. In the
