ENEA Thermodynamic Solar Project Prepared by Mauro Vignolini Presented by A. Fontanella
ENEA objective To produce electricity by solar plant at high temperature (550 C) using molten salt. the advantages are: Higher solar plant efficiency Lower solar electricity cost Higher storage efficiency Integration with combined gas cycle plant
ENEA Roadmap: by labs to industrial demonstration (10 years) ENEL Archimede 5 MWe Started on July 2010 Industrial Demonstration plant 2008 2009 2010 Demo design and construction Industrial role 2007 Lab R&D Test facility PCS 2001 2002 2003 2004 Project Start-up 2005 2006 Prototype Operation start-up Prototype Design Components test and qualification 70 employers Government role
Key element The key element for the diffusion of CSP technology is to reduce the cost of electric energy produced to a level compared with power plants based on fossil fuels. At present the cost of the electric energy from CSP is about 17 24 c /kwh, 2-4 times the energy of fossil fuel The ways to reduce the CSP cost of energy are: increasing of efficiency reduction of manufacturing cost localization in areas with higher solar radiation
Cost reduction: Experience effect Within 2025 CSP is expected to be competitive against fossil fuelled power plant
Cost reduction: localization effect Increasing irradiation level offer further potential to decrease cost of electricity (- 4,5% per DNI increase of 100 kwh/m 2 a) Transmission cost is 0.06-0.07 c /kwh per 1.000 km (do not outweigh the advantage of lower electricity production cost)
Solar Plant Cost Breakdown Project development : land purchase, permission. (6-7%) Engineering/planning : engineering/planning, EPC management. (8-11%) Technology (procurement) : solar field, thermal generation system, storage system, electrical generation system. (60-68%) Construction/site improvement. (2-3%) O&M cost : plant operation, maintenance. (1,5%) Other project cost: project insurance, contingency, risk fees. (15-17%)
Technology innovation: Molten salt as heat carrier and thermal storage Salt mixture Sodium Nitrate (NaNO 3 ) Potassium Nitrate (KNO 3 ) 60% - 40% Advantages: High working temperature (550 C) Atmospheric pressure in the thermal storage Lower volume and cost for thermal storage Used as a fertilizer
Technology innovation: A new design for receiving tube ENEA patent Coating Highest temperature (550 C) and efficiency in the world coating stable in air
Technology innovation: support structure of solar collector Competitors Patent ENEA Wing rib ENEA
Technology innovation: Tracking System MAIN FEATURES High torque ( 130 knm) Variable rotating speed (0 0,61 sec/degree) Low current absorption (5,5 A) High precision ( < 0,17 mrad)
Technology innovation: Reflecting panel manufacturing Composite material and thin glass
Test facility for components and system qualification Upside of the Storage ENEA Casaccia labs (Rome) - Started-up April 2004 Storage Investment 5,43 M
Archimede project: Demonstrative plant in collaboration by ENEA Owner ENEL (electrical utility) Technology and design ENEA Power 5 MWe Placed in Siracusa (Sicily) Storage 7 hours ENEL Archimede will start on June 2010
Archimede solar plant layout ENEL Gas Combined Cycle Solar field DNI 1936 kwh/ m 2 y Number of SCA 54 Solar field area 30600 m 2 Thermal output 28,3 GWh/y Field efficiency 48% Thermal storage 100 MWh (8 h) Nominal power 4,7 MWe Net electrical output 8,7 GWhe/y Solar to electricity 14% Energy saving 1921TEP/y Emission avoid CO 2 6000 t/y
Final remarks ENEA started 10 years ago with a vigorous research, development and demonstration program on CSP and introduced many innovations. ENEA has several patents concerning solar components. ENEA has many R&D activities on the components Technology is ready for industrial development The main objective obtained is the development of Italian firms specialized in manufacturing of components for solar power plants