Innovation and entrepreneurialism are driving forces in the age of renewable power and digital technology. When it comes to thinking outside of the box, the city of Portland, Ore., has a well-earned reputation.


In January, it bolstered its credentials with an unlikely means of generating power. The Portland Water Bureau (PWB) and Lucid Energy announced that they were turning one of the city’s major water pipelines into a source of renewable power. The system uses the gravity-fed water flow to spin turbines that produce electricity. Power from the generators is sold to the Portland General Electric under a 20-year power purchase agreement.


The 200-kilowatt system consists of four 42-inch turbines installed in one pipeline beneath the streets of downtown Portland. It is expected to generate about 1,100 megawatt-hours (MWh) of electricity per year, enough to power about 150 homes.


The turbines use a lift-based, vertical axis spherical design that fits inside large-diameter (24–96 inches) pipes. Water flows through the hydrodynamic apparatus, generating power as the turbine spins. Due to its lift-based design, the system generates power across a very wide range of flow conditions, volumes and velocities.


The turbines extract very little head pressure, just 1–6 pounds per square inch. This allows for uninterrupted water flow and the placement of the turbines in series. The company boasts that the Portland project will have no environmental impact and will not affect water quality or delivery.


The first LucidPipe application was installed in a water pipeline of the Western Municipal Water District in Riverside, Calif. The pilot fed more than 20 MWh of renewable electricity to the grid, and the Riverside Public Utilities subsequently installed a permanent system.