Design-build firm McKinstry has teamed up with Washington's Covington Water District (CWD) to install a new hydropower turbine in the utility district’s water main. Now fully operational, the turbine will generate roughly 70% of the annual energy consumed by CWD’s administrative facilities, reducing energy and operating costs for the utility district.
The turbine system, custom manufactured by Washington-based Canyon Hydro, was installed in a new water transmission line that connects CWD to Tacoma Water. The 170-foot drop between the Tacoma Water source and CWD’s system causes substantial pressure buildup. Traditionally, a pressure reducing valve (PRV) is used to reduce this pressure, which causes energy to be lost as heat and noise. The new turbine installation will reduce the water pressure while also generating energy. McKinstry implemented the turbine system alongside Canyon Hydro, Gray & Osborne and CWD.
“Covington Water District needed to build the new water line anyway, so we wanted it done the right way, focusing on innovation and sustainability,” says Thomas Keown, general manager at Covington Water District. “Not only will the turbine reduce our energy costs by supplying 70% of our administrative site’s power, but we will also cut energy waste by using this new, efficient technology.”
In addition to capturing energy that would have otherwise been lost, the project is also environmentally beneficial by reducing the need to run well pumps to pull water out of the ground. While the turbine runs 24/7, McKinstry will continue to verify the system’s performance and guarantee the energy savings for the term of the performance contract.
“Efficiency and innovation were Covington Water District’s focus for their new pipeline,” says Andrew Williamson, McKinstry’s municipal business manager. “We built a great team that pushed sustainability while understanding the need to be able to advance water flow and net energy metering. We provided the turbine to generate power in place of a conventional pressure reducing valve, taking advantage of the district’s new transmission line that was required to address system resiliency.”
The Washington State Department of Commerce awarded the district a grant through the Energy Efficiency and Solar Grants program that helped cover 25% of the project’s cost. The energy savings performance contract (ESPC) with McKinstry was executed and administered by the Washington State Department of Enterprise Services (DES) Energy Program. To date, the DES Energy Program has managed more than $1.2 billion in ESPC projects, saving its public-sector clients more than $40 million in annual avoided utility costs.
“This is an excellent example of how energy savings performance contracting can be used to find innovative solutions that deliver renewable energy,” says Doug Kilpatrick, energy engineer for the Washington State Department of Enterprise Services. “The new turbine will bring cost savings to the Covington Water District for years to come.”
McKinstry will execute regular follow up inspections to ensure the turbine is meeting operational and energy savings expectations.