Covington Water District introduces a hydro turbine to save money

The turbine will save the water district about $16,000 annually.

The Covington Water District (CWD) has teamed with McKinstry to install a new hydropower turbine in the utility district’s water main.

This will generate about 70 percent of the annual energy consumed by CWD’s administrative facilities, which will reduce energy and operating costs for the district, and will cut energy waste as well, it stated in a press release from Mckinstry.

A hydropower turbine is a pump in reverse said Tom Keown, general manager at Covington Water District.

“So in a pump, you would add power to the pump, which would then turn the motor, which would then in turn, turn the propellers inside the pump and boost the water from point A to point B,” Keown explained. “In this case, it’s literally just the exact opposite. What you’re doing is running water through the propellers, which turn a rotor, which is on a shaft that then turn the generator on the back end side of the unit. That generator then produces power, which is then routed over to feed our building.”

McKinstry is a national full-service, “design-build-operate-and-maintain,” firm that specializes in consulting, construction, energy and facility services, according to the press release.

According to Keown, the district partnered with McKinstry about three years to do an energy audit study to find a way to save the district money.

“I’ve been the general manager now for about four years and prior to joining the district I was an engineering consultant and I was exposed to energy service companies and the serves that they offer in my consulting role working with other utilities so when I started at the District I had just asked if we had ever done an energy audit of the district and the district’s utilities and the answer was ‘no,’” Keown explained.

He said to successfully do this study, he and the district had to look at everything from the light bulbs that were in use to their pump stations. The key, he said, was to see if there were any misapplications or better applications that could be used to reduce energy needs.

The new turbine system ended up being installed in a new water transmission line that connects to the Tacoma Water District.

“The 170-foot drop between the Tacoma Water source and CWD’s system causes substantial pressure buildup. Traditionally, a pressure reducing valve 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,” the release said.

To cover the cost of this turbine project, The Washington State Department of Commerce provided a grant to cover 25 percent of the project’s cost. The energy savings performance contract with McKinstry was executed and administered by the Washington State Department of Enterprise Services (DES) Energy Program, the press release said.

To date, the DES Energy Program has managed more than $1.2 billion in energy saving projects, saving its public-sector clients more than $40 million in annual avoided utility costs.

In the Covington Water District, Keown said this turbine will save about $16,000.

“Our annual power bill is just over $20,000 and it’ll save us about 70-75 percent. That’s today, there’s also space set aside in the turbine generation building for future growth. We actually have it set up in the next 10-15 years, if you look at our growth patterns, we’ll probably be in a position where we could add an additional turbine at that point,” he explained.

McKinstry will execute regular follow up inspections to ensure the turbine is meeting operational and energy savings expectations, the press release said.