According to the U.S. EPA, water and wastewater facilities spend about $4 billion per year to treat water, operating costs that represent up to one-third of a city’s energy bill. A 2009 River Network report estimates that water-related energy use is at least 521 million MWh a year, representing 13% of U.S. electricity consumption.
Driven by rising expenses, water managers in California, Oregon, and Texas are replacing sections of old transmission pipeline with steel pipe that uses the energy inherent in flowing water to offset overall operational costs.
The LucidPipe Power System from Lucid Energy of Portland, Ore., and Northwest Pipe Co. of Vancouver, Wash., relies on a patented, spherical turbine that operates inside gravity-fed steel water pipes 30 to 96 inches in diameter, or generally 6 to 18 inches wider than the turbine.
Designed to generate power without disrupting flow, one LucidPipe Power System turbine produces up to 100 kilowatts of electricity. The technology works at lower flow velocities, but energy production increases as velocities increase. Best performance and reliability is achieved at velocities greater than 4 ft/s.
Lucid Energy has been developing the unit since 2007 and formed a strategic relationship with Northwest Pipe Co., the largest U.S. manufacturer of water transmission pipe, in 2008. Fueled by a $1 million U.S. Department of Energy Small Business Innovation Research grant, the companies developed a lift-based in-pipe design, more similar to a wind turbine than traditional in-pipe hydro turbines, that enables the turbine to produce electricity without impacting pipeline operations or flow rates.
Unlike wind or solar, which are intermittent and weather-dependent, the flow of water in pipelines is far more predictable and constant. Also, because the turbines operate inside the pipeline, no environmental impact review is necessary before installation.
“Lucid showed us how to turn the extra energy we were wasting each day into power with minimal changes to existing infrastructure,” says Todd Jorgenson, water operations manager for California’s Riverside Public Utilities, which debuted the first prototype inside 42-inch concrete-lined steel pipe in February 2010. “Now we have a system that will provide us with renewable energy for years to come.”
Lucid Energy, which funded the prototype project, subsequently installed three more pilot versions at the utility following extensive testing at the Utah Water Research Laboratory to optimize blade materials, configurations, and other design aspects for maximum component lifetime, energy output, and efficiency. The pilot program earned the utility a 2011 Outstanding Energy Management Award from the American Water Works Association’s California-Nevada section.
In April 2012 the utility became the site of the first U.S. commercial installation. A single 42-inch, 20kW turbine inside a 60-inch pipeline delivers groundwater from a canal about 25 miles to a reservoir in Riverside for drinking and irrigation. The turbine is placed upstream from a valve used for flow control.
Electricity produced is fed directly to the utility. The system is maintained by Lucid Energy and is expected to produce 100 to 150 MWh (energy is measured in megawatt-hours) per year.