Enel Green Power North America (EGPNA) added a fully submersible downhole generator to a geothermal injection well at its 25MW Cove Fort geothermal plant, which started operations in 2013.

The company claims that it is the first commercial facility to combine binary cycle geothermal power with hydro technology.

The technology captures the energy of the water flowing back into the earth to produce further electricity and better control the flow of brine back into the ground.

It increased the plant’s output by 1,008MWh between July and September, offsetting energy consumption by 8.8%.

The generator’s presence creates pressure which in turn reduces the pressure of the brine flow. This reduces the brine turbulent flow into the well and minimises the damage it can do to the well.

The Cove Fort geothermal site generates about 160 GWh of power per year, powering over 13,000 US households. It reduces about 115,000 tonnes of CO2 emissions a year.

It is the second hybrid power plant of EGPNA in the US, the first being Stillwater facility in Nevada. The power plant had integrated binary cycle geothermal, solar thermal and solar PV technologies at the same site.

Enel Global Renewable Energies head Francesco Venturini said: "The operation of this technology, a world’s first, is a major milestone for the geothermal industry and a reinforcement of our commitment to innovation and energy efficiency.

“We are creating innovative solutions that are making renewable energy better, stronger and smarter.

“As a result we have once again discovered a more resourceful way to maximise plant operations and power generation with the aim of using this technology at our facilities around the world.”

Image: Enel’s headquarters in Italy. Photo: Courtesy of Sergio D’Afflitto/Wikipedia.