Shams uses parabolic trough technology to convert solar irradiation into solar heat, which is fed into a steam turbine to provide power generation.
The steam exiting the steam turbine is condensed with an air-cooled condenser.
The solar field is a modular distributed system of solar collector assemblies (SCAs) connected in parallel via a system of insulated pipes. Cold heat transfer fluid (HTF) flows at approximately 280°C-300°C from the steam generator into a cold HTF header that distributes it to 192 loops of SCAs in the solar field. Each loop consists of four SCAs. HTF is heated in the loop and enters the hot header, which returns hot HTF from all loops to the solar steam generator. The HTF enters the solar field at 280°C-300°C and leaves the field at 400°C.
The SCAs collect heat via a trough of parabolic mirrors, which focus sunlight onto a line of heat collection elements (HCE), welded in line at the focus of the parabola. The mirror-HCE trough is mounted on a mechanical support system that includes steel pylons and bearings. Single-axis tracking of the sun ensures best use of sunlight.
The absorber tubes are contained within the HCE and serve to convert solar irradiation to heat. A dual-fuel fired HTF heater (gas or diesel) is used in the HTF loop to provide the required thermal energy during cloud cover or low-solar insolation to avoid shut down of the steam turbine and ensure Shams is capable of producing its 100MW capacity power output.
In the solar steam generator, the HTF generates steam with a temperature of approximately 380°C. To enhance the efficiency of the steam turbine, the steam is further heated in a dual-fuel fired booster heater to a temperature of 540°C. The superheated steam is supplied to the condensing steam turbine, which generates power. An air-cooled condenser is used to condense the exhaust steam flow coming from the steam turbine. The condensate is then returned to the solar steam generator.
The parabolic trough power plants use parabolic trough collectors as solar field to concentrate the direct solar radiation onto a tubular receiver. These collector fields supply the thermal energy to drive a steam turbine. Shams Power Plant parabolic trough solar field has 192 total loops with 4 Solar Collector Assemblies (SCAs) per loop and 12 Solar Collector Elements (SCEs) per SCA.
The Heat Transfer Fluid (HTF) Main Pumps circulate the thermal oil through the parabolic trough solar field allowing to maintain the pressure on the primary circuit and to heat it up and pump it to the solar steam generator.
The Expansion System allows to compensate the contraction and expansion of the thermal oil due to the temperature variations of the working fluid along the daily operation.
The Heat Transfer Fluid (HTF) Heaters are used to heat up the thermal oil when the temperature of the HTF through the parabolic trough solar field decreases below the freezing temperature and the weather conditions do not allow to increase the temperature. The main function of these HTF heaters is anti-freezing purposes, but additionally, they are also used to allow a quicker start-up of the parabolic trough solar field.
The steam generator system allows the generation of superheated steam by exchanging the heat provided by the thermal oil (HTF) and collected through the solar parabolic trough collectors.
The Booster Heaters are the responsible of providing a higher superheating degree to the steam generated in the Steam Generation System, which allows generating electricity with a higher efficiency in comparison with a conventional parabolic trough solar power plant.
The Steam Turbine Generator unit is part of the system responsible of converting the thermal energy provided by the superheated steam into mechanical and electrical energy.
The Air Cooled Condenser is in charge of condensing the steam by ceding latent heat from the steam turbine exhaust steam to the fan-driver air.