La Porte wastewater plant reports 1-MW solar field, 13-year payback estimate and ongoing maintenance needs

Jerry, a city wastewater staff member, told the La Porte Sustainability Commission the city built a 1-megawatt solar field sited on land partly converted from corn and an old sludge lagoon and that the array was chosen over wind and expanded biogas because “solar would be simple,” the system has been “remarkably, trouble free” and it produces substantially more power than the plant needs during summer months.

The solar field supplies daytime electricity to both the treatment plant and NIPSCO under an existing net-metering agreement, Jerry said. He described a seasonal pattern: the plant uses about 250 kilowatts, the array can produce almost a megawatt in strong sun, and the plant builds a summer credit “bank” that reduces winter bills. Jerry said the plant currently sees about $25,000 in avoided…