Innovative Energy Project Earns Recognition

Posted Friday, July 22, 2022

The American Cities Climate Challenge named Skagit PUD’s micro-hydroelectric power project 10 of the Most Noteworthy Local Government Renewables Deals of 2021.

In July 2021, Skagit PUD installed the first pressure recovery project in Washington state that uses the In-PRV from InPipe Energy, a new intelligent water and micro-hydro system that generates electricity by harvesting excess pressure from municipal water pipelines. The In-PRV is a class of hydroelectricity known as conduit hydropower. Unlike traditional hydropower, electricity from the In-PRV does not harm fish or ecosystems.

Utilities typically use a lot of energy pumping water over long distances. Water is pumped up to a high point, stored in reservoirs, and then flows by gravity to low parts within the system. The water is at high pressure. Too high for typical domestic and commercial uses. The pressure is reduced via friction; in this case, the PUD uses a hydroelectric turbine to provide that friction and capture the electricity.

By recovering the energy embedded in excess water pressure and converting it into electricity, the 22-kilowatt system can generate up to 94,000 kilowatt-hours (kWh) or more of electricity per year while providing pressure management that helps save water and extend the life of the pipeline. The electricity produced can be used to offset the use of grid power at Skagit PUD’s East Division Street pump station in Mount Vernon, saving the district (and its ratepayers) money and replacing the equivalent of 1,587 metric tons of fossil-fuel-based carbon emissions annually.