Flowserve Corporation’s pumps are performing to expectations in critical applications at the world’s first commercial concentrated solar power (CSP) plant utilising a central tower receiver with thermal storage capabilities.

Located near Seville, Spain, the 19.9 megawatt (MW) Gemasolar power plant employs molten salt as the heat transfer fluid, an innovative technology that allows for the continuous generation of electricity 24 hours a day for many months throughout the year.

Due to the molten salt storage design, the CSP plant is capable of energy production for up to 15 hours without sunlight, helping to avoid fluctuations in the region’s power supply.

At the heart of the CSP plant are seven specially-configured Flowserve vertical turbine pumps (VTPs) capable of sustaining temperatures up to 600°C (1,100°F) and generating pressures up to 100 bar (1,450 psi). Materials of construction for these high process temperatures include stainless steel alloys to minimise thermal growth and forestall shaft deflection.

These pumps are designed for excellent heat dissipation and include Flowserve dry gas fluid sealing systems to specifically handle the molten salt. In addition, low pump submergence allows the liquid level to be drawn down further in the storage tanks for greater energy generation. These specially-adapted VTPs may be deployed in pump lengths up to 20 metres (65 feet).

Tom Ferguson, President of Flow Solutions Group, said in a company press release, “Our close relationship with SENER, as well as our 70 years of experience in molten metal pumping applications, was crucial in the successful commissioning of this unique solar power plant.”

“This collaborative effort required a high degree of coordination as we assessed the application, chose the proper construction materials and implemented the design features and pumping system components necessary for this historic project.”

Located in the Andalucia region of Spain, the innovative power plant supplies electricity to 25,000 homes and is expected to reduce carbon dioxide emissions by more than 30,000 tonnes annually. Managed by Torresol Energy, a joint venture between SENER (the leading Spanish engineering and construction company) and Masdar (Abu Dhabi’s future energy and clean technology company), the Gemasolar station incorporates 2,650 large, sun-tracking heliostats (mirrors) to focus sunlight on the top of a centrally located tower.

Currently, Torresol Energy has started the commercial operation of the Gemasolar plant, with 19.9 MW and central-tower technology and heliostat field, located in Fuentes de Andalucía, in Seville. At the same time, the company is building two other plants, Valle 1 and Valle 2, two twin installations with cylindrical-parabolic collector technology, 50 MW each one, located in San José del Valle, in the province of Cadiz.