Enel, with its subsidiary Enel Green Power, inaugurates in Stillwater the first plant in the world capable of operating with three technologies, all green. And, at the same time, it announces that it has won the tender in Mexico for 3 photovoltaic plants for a total of 1000 megawatts. In Nevada the Italian Prime Minister Matteo Renzi wanted to inaugurate the first stage of his trip to the USA, just to underline the innovative value of the system. Together with him the managing directors of Enel and Enel Green Power, Francesco Starace and Francesco Venturini, and the governor of the state of Nevada Brian Sandoval. Stillwater is the first power plant in the world to combine medium enthalpy binary cycle geothermal, solar thermal and solar photovoltaic technologies on the same site.
ONE SYSTEM, THREE TECHNOLOGIES
“Stillwater testifies to Enel Green Power's pioneering and innovative technology that has made the company an example of success in collaborating with governments and industrial partners around the world to address issues related to the environment and climate change through the use of renewables – said Starace -. The lessons learned at this advanced solar-geothermal facility will make a major contribution to the development of other hybrid plants around the world. We will continue to invest in new technology solutions to maximize existing assets and drive further growth, while maintaining our strategic focus on innovation and operational efficiency."
The integration of different generation technologies in a single site makes it possible to increase the availability of the renewable energy resource and reduce its intermittence. Geothermal and solar (thermodynamic and photovoltaic) are complementary, as solar production increases on the hottest and sunniest days of the year, when the thermal efficiency of the geothermal plant is lower. The increased power delivery at peak hours also allows for a more load-following production profile. At the same time, sharing existing infrastructure promotes cost savings and a reduction in the plant's environmental impact per unit of energy produced and delivered.
Based on the results of a research conducted between March and December 2015, the integration of a 2 MW thermodynamic solar plant with a 33,1 MW geothermal plant allowed an overall increase in Stillwater's production of 3,6% compared to the geothermal. These results were further confirmed by a study on the integration of geothermal and solar thermal, and it is the first time that the empirical data produced by a commercial hybrid plant validates a theoretical hybrid model. This work was performed under the Cooperative Research and Development Agreement (CRADA) with the National Renewable Energy Laboratory (NREL) and Idaho National Laboratory (INL), under the supervision of the US Department of Energy's Office of Geothermal Technologies .
The Stillwater Hybrid Plant has been awarded Geothermal Energy Association Honors in the Technology Advancement sector for four consecutive years, in 2012, 2013, 2014 and 2015. It went online in 2009 with the completion of the geothermal power plant, since Stillwater serves as an innovation hub for Enel Green Power (EGP). Making the most of its international presence, resources and partners, EGP draws on its diversified portfolio of renewables and the most advanced plants worldwide to formulate creative and innovative ways to maximize plant management and production.
In 2012, the company added a 26,4 MW solar PV unit to the geothermal plant – at the time one of the largest PV plants of its kind in the United States. In 2015, it developed a solar thermodynamic system to work in conjunction with the existing Stillwater geothermal power plant. By combining three renewable sources on the same site for the first time, EGP has managed to exploit the assets already installed, creating a more productive plant.
FIRST PLACE IN MEXICO
In Mexico, on the other hand, Enel Green Power (EGP), through its subsidiary Enel Green Power Mexico, was awarded the right to sign contracts for the supply of energy for 15 years and green certificates for 20 years with three solar photovoltaic projects, for a total installed capacity of approximately 1 GW (1.000 MW), in the first long-term public tender held in the country since the introduction of the energy reform. EGP was awarded more capacity than any other operator that took part in the tender, confirming its position as the largest renewable operator in Mexico in terms of installed capacity and project portfolio. EGP will invest about one billion US dollars in the construction of new plants, in line with the investments envisaged in the company's current strategic plan. Each of the three projects will be supported by a contract for the sale to the Comision Federal de Electricidad (CFE) of specific volumes of energy for a period of 15 years and the related green certificates for a period of 20 years.
