Renewable Energy

Utilities look to turn their water pipes into hydropower

Faced with falling revenue because of water conservation, some utilities are looking to make money from the water pipes they already have in the ground—and creating low-cost hydroelectric energy in the process.

Workers with an in-pipe hydropower system in Portland, Oregon.
Source: Lucid Energy

"Small hydropower" captures electricity by using water that flows through a pipe to turn micro turbines in the lines, or by harvesting energy from stream flows in irrigation canals and streams. Other technology on display at a water expo in Anaheim, Calif., this week included the latest in pumps, pipes and smart water meters, as well as leak detection and filtration systems.

"Many agencies are not going to the municipal bond market, but instead going to private banks to put separate debt vehicles right on these little hydro units and creating a new revenue line," NLine Energy founder and CEO Matt Swindle said in an interview at the ACE15-American Water Works Association (AWWA) Conference and Exposition.

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Venture capital and crowdsourcing funds have flowed into the space. Some of the big companies active in the solar and wind markets also finance small hydropower systems that can generate revenue that's then reinvested into infrastructure work. That's potentially a significant development in places like California, where a serious, four-year drought is cutting into water utilities' revenue.

"Private capital is willing to finance projects for cities that need to rebuild their water and energy infrastructure," said Gregg Semler, president and CEO of Portland, Ore.-based Lucid Energy, which has hydropower systems installed in Southern California and Oregon. The Lucid CEO met this week with a delegation from South Africa that's considering installing in-line hydropower equipment in Johannesburg.

"We're inundated with interest from municipalities and water agencies all over the world," said Semler.

California's drought drama and how we got here
California's drought drama and how we got here

Apple has embraced the high-tech hydropower space and partnered with California-based Natel Energy on a project in central Oregon that utilizes an existing irrigation canal to generate renewable energy.

"We are working with Apple to provide them with green energy that goes into their whole nationwide portfolio of energy," said Natel Energy Vice President Eric Thompson. Apple revealed in its latest "Environmental Responsibility" report that its data center in Prineville, Oregon, includes "a micro-hydro system that harnesses the power that's been flowing through local irrigation canals for over 60 years."

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According to Thompson, big turbines used by large dams are capable of generate 100 or 500 megawatts or more, but the "low-head," or micro hydropower systems, can be distributed as an alternative to large dams and are about half as expensive on equipment costs and about half as expensive to install. "We could generate in aggregate tens of gigawatts of energy in the U.S. alone," he said.

Meanwhile, AWWA's 2015 State of the Water Industry Report, released in conjunction with this week's conference, found that water professionals' top concerns are "renewal and replacement of aging water and wastewater infrastructure," as well as how to finance capital improvements.

Interestingly, the category "drought or periodic water shortages" failed to make the top-10 list of concerns in the 2015 report after coming in at No. 8 last year. It found 43 percent of utility respondents reported that their total water sales are declining.

"There's still a bit of a mind change that needs to take place in California where people think about water every time they use it," said Geoffrey Gray, a development official with the Australian Water Association, which had its own booth at the show to showcase what it learned about water conservation and technology after Australia's experience with the Millennium Drought.