A recent study between Sandia National Laboratories and Siemens Energy, Inc., published on March 2013 [11], confirmed the feasibility of adapting the Siemens turbine SST-900 for supercritical steam in concentrated solar power plants, with a live steam conditions 230-260 bar and output range between 140-200 MWe. In this context, this analysis is focused on integrating a linefocus solar field with a supercritical Rankine power cycle. For this purpose two heat transfer fluids were assessed: direct steam generation and molten salt HITEC XL. The design-point conditions were 550ºC and 260 bar at turbine inlet, and 165 MWe Gross power output. Plant performance was assessed at design-point in the supercritical power plant (between 43-45% net plant efficiency depending on balance of plant configuration), and in the subcritical plant configuration (~40% net plant efficiency with one DRH, and up to ~41% with two DRH stages). Direct Reheating was adopted in Rankine power cycle to avoid any intermediate heat exchanger. Seven feed-water heaters optimized the plant performance power output.
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Zarza E., Valenzuela L., Leon J., Weyers H.D., Eickhoff M., Eck M. And Hennecke K., "The DISS Project: Direct Steam Generation in Parabolic Trough Systems. Operation and Maintenance Experience and Update on Project Status", Journal of Solar Energy Engineering, 124 (2), 126-133, (2002)
Eck M., Zarza E., Eickhoff M., Rheinländer J., and Valenzuela L."Applied research concerning the direct steam generation in parabolic troughs, Solar Energy, 74 (4), 341-351, (2003)
M.Seling, Novatec Solar GmbH. "Two years experience in operating the largest commercial Fresnel CSP Plant". SolarPaces 2014, Beijing, China.
A.Khenissi. "Return of Experience on Transient Behaviour at the DSG Solar Thermal Power Plant in Kanchanaburi Thailand". SolarPaces 2014, Beijing, China.
G.Morin, Novatec Solar GmbH. "Molten Salt as Heat Transfer Fluid in a Linear Fresnel Collector Comercial Application Backed by Demonstration ". SolarPaces 2014.
A.Maccari, Archimede Solar Energy. "Archimede Solar Energy Molten Salt Parabolic Trough Demo Plant: A Step Ahead Towards the New Frontiers of CSP". SolarPaces 2014.
F. Matino, Archimede Solar Energy "Molten Salt Receivers Operated on Parabolic Trough Demo Plant and in Laboratory Conditions". SolarPaces 2014.
Bruce Kelly,"Advanced Thermal Storage for Central Receivers with Supercritical Coolants", Abengoa Solar Inc. DE-FG36-08GO18149, June 2010.
T.Hirsch, A.Khenissi, "A systematic comparison on power block efficiencies for CSP plants with direct steam generation", Institute of Solar Research, German Aerospace Center (DLR), SolarPaces 2013.
L.Coco-Enríquez, J.Muñoz-Antón, J.M. Martínez-Val. "Innovations on direct steam generation in linear Fresnel collectors". SolarPaces 2013, Las Vegas, U.S.
James E. Pacheco, Thorsten Wolf, Nishant Muley "Incorporating Supercritical Steam Turbines into Advanced Molten-Salt Power Tower Plants: Feasibility and Performance", Sandia report, SAND2013-1960, March 2013.
EPRI. Electric Power Research Institute. G8 Cleaner Fossil Fuels Workshop. Stu Dalto, Director, Generation, IEA Secretariat, Paris France, 17-18 January, 2008."Boiler material for USC pulverized coal (PC) Plants".
F.Burkholder and C.Kutscher "Heat Loss Testing of Schott's 2008 PTR70 Parabolic Trough Receiver", report NREL/TP-550-45633, May 2009.
Novatec Solar, "SAM Linear Fresnel solar boiler model, SAM Webinar", NREL SAM Conference 2013