Effective November 1, 2021 Virginia’s steam district will have gone from roughly 1,800 customers spread Southside to Northside in 2007 to roughly 300 customers located primarily in and around the downtown business district. There was a time in the 60’s when roughly 3,000 customers were served by the Utility’s co-generation plant. In the 1920’s and 1930’s it was the safest and cleanest way to heat a house. Then, in the 60’s, electric heating came of age, and in the 1980’s natural gas heating began attracting steam customers. The 90% reduction in customers is roughly an 85% reduction in pipe and yet only a 50% reduction in sales. For the past three years the Utility has been taking proactive measures to reduce steam losses in the remaining downtown core district. The Utility has plans to re-evaluate the viability of the Core district in 2023.
Prior to the Steam Conversion project, which began in late 2017, district steam was provided by extraction from the City’s cogeneration turbine/generators (high pressure steam used to spin a turbine which generates electric power. The steam coming out of the “back end” of the turbine is sent to the steam heating district. In its day this was a highly efficient means of both generating power and providing heat. The Utility used two coal boilers (#7 and #9 – #9 which has been de-commissioned) a gas boiler #10, and a biomass/gas boiler #11, to provide the steam for generation. With the elimination of power generation, steam from these boilers is sent directly to the steam district, but as the steam district’s size is reduced, larger boilers are unable to operate in an environmentally safe manner at such low levels. Currently we are retaining our #7 – 70,000 pph coal boiler, our #10 – 225,000 pph natural gas boiler, and our 110,000 pph biomass/gas boiler. In the meantime the Utility has installed a small 50,000 pph natural gas steam boiler to be able to handle anticipated steam loads in the future, and will be installing an additional such boiler, the size not yet determined, to provide system redundancy and low end production capability.