Enel Green Power has inaugurated its Stillwater renewable energy hybrid facility in Nevada.
Stillwater combines medium enthalpy, binary cycle geothermal, solar thermal and solar photovoltaic technologies at the same site.
EGP said that by combining different generation technologies at one site, energy availability is increased and energy intermittency reduced.
It said geothermal and solar – both thermal and PV – are complementary, meaning that production from solar is higher during the sunniest and hottest days of the year, when the thermal efficiency of the geothermal plant is lower.
“The increased delivery of power during peak hours also enables a more load-following production profile. At the same time, sharing existing infrastructure enables costs-savings and reduction of the plant’s environmental impact per unit of energy produced and delivered,” the company said.
EGP said research conducted between March and December 2015 found that the combination of a 2MW solar thermal facility with a 33.1MW geothermal plant increased overall output at Stillwater by 3.6% compared with production from geothermal only.
The Stillwater geothermal plant started operating in 2009.
In 2012, the company added a 26.4MW solar PV unit to the geothermal plant.
A solar thermal system to operate in conjunction with the existing Stillwater geothermal power station was designed in 2015.
The facility’s inauguration was attended by Italian Prime Minister Matteo Renzi, Enel chief executive officer Francesco Starace, Enel Green Power CEO Francesco Venturini and Nevada Governor Brian Sandoval.
Starace said: “The lessons we are learning at this advanced geothermal-solar facility will be key to the development of other hybrid plants throughout the world.
“We will continue to invest in new technological solutions to maximise existing assets and support further growth, maintaining innovation and operational efficiency as a key driver of our strategic plan.”
Image: the Stillwater facility (Enel)
