Pumping station hasfirst DifGEN
The Coldbrook Pumping Station, which is part of the Grand Rapids Water System, is the first facility of its type in the nation to have the water-utility industry's latest technological advancement installed. That accomplishment is likely to add to the city's ongoing saga of being the most sustainable midsized metropolitan area in the country.
The high-tech gadget is called the DifGEN. In layman's terms, it combines a valve with a generator. The valve maintains water pressure for the station's customers, while the generator captures the electricity the pumping action uses and distributes it throughout the Monroe Avenue facility. Being able to control water pressure and produce electricity at the same time is a first for the water-utility sector.
Zeropex, a Norwegian firm with a U.S. division based in Birmingham, Mich., makes and distributes the DifGEN. The device replaces pressure chokes, closes the energy loop and reduces a facility's carbon footprint. The city's water system recently bought one for $150,000.
City Water System Manager Joellen Thompson said her department expects to recoup that expense in five to six years because the DifGEN is expected to save the station about $30,000 a year in electricity costs. A year's electric bill for the facility runs about $240,000, and the DifGEN, which has a projected operational life of at least 30 years, will cut that tab by 12 percent.
"It has somewhere between a five- and a six-year-payback period based on the calculated energy savings that we will recover by using the valve," said Thompson. "We had nothing exactly like this in our system. But, typically, valves last for 30 years.
"The way this works is, the water, as it flows through this valve, will turn two rotating elements, which captures that energy. That energy, in turn, turns the generator and generates the power. With the valve we have now, we just bleed that water back into the low-pressure system and we basically just waste that energy. … So here we're using that higher pressure to turn the generator," she explained, adding that the device was made in Ohio.
Haris Alibasic, an assistant to City Manager Greg Sundstrom, said the electricity the DifGEN will manufacture should help the city move closer to its goal of operating on 100 percent renewable energy by the year 2020.
Thomson said the city learned about the DifGEN from Zeropex U.S. Vice President of Sales and Marketing Sven Anden, who is based in the Birmingham office. Anden came to the city earlier and spoke with The Right Place Inc. President Birgit Klohs about marketing opportunities, and Klohs directed him to City Hall. Anden met with Thompson, Alibasic, Deputy City Manager Eric DeLong and Grand Rapids Mayor George Heartwell last fall.
"Of course, the first question that came up was where else was this being used, and it wasn't, in the United States. So we couldn't go anywhere and look at it. But it is used widely in Europe. So we gathered more information and got to a point where we felt comfortable with it. We also reviewed the device with our regulatory agency, which is the MDNRE, to make sure that they didn't have any concerns," said Thompson.
Anden told the Business Journal that Zeropex U.S. is receiving inquiries about the DifGEN from western states, like California, and Canadian provinces, like British Columbia. He said the company's device has a higher efficiency rating in capturing energy than either solar or wind systems, as the DifGEN is from 71 percent to 75 percent efficient. Anden also said that Coldbrook will become a popular site for those in the water-utility business. "People will be coming here from all over to see this," he said.
The Coldbrook Pumping Station is just one facility in the city's water system. There are about two dozen sites altogether, and Thompson said some of those may be looked at for a DifGEN.
"There are other locations in our system where we drop the pressure and essentially have a similar energy loss, but not of the same size," she said. "Coldbrook is where we have the largest continuous energy loss. And it's in a building where we use energy, so it's an ideal location to try this valve and see how it works. But there may be other locations where it would be beneficial, as well, and we'll be looking at those."
Thompson also pointed out that there could be some opportunities down the road for local firms to work with Zeropex U.S., with the city serving as the company's national showplace for the DifGEN.
"We're hoping that being the first location in the U.S. may provide opportunities for local engineering firms, local contractors or other support services to partner with the Zeropex folks to help them work on other installations in the U.S."