Concentrating Solar Power (CSP): Technology, Markets, and Development
Craig S. Turchi, PhD
[email protected] National Renewable Energy Laboratory Golden, Colorado, USA
September 2009
National Renewable Energy Laboratory Innovation for Our Energy Future Outline
• Technology Overview − Parabolic Troughs − Linear Fresnel − Power Towers − Dish / Engine Systems • CSP Siting, Integration and Markets • Projects • Research & Development Focus
National Renewable Energy Laboratory 2 Innovation for Our Energy Future CSP Technologies and Market Sectors
CSP w/ Storage (Dispatchable) – Parabolic Trough – Power Tower – Linear Fresnel
CSP w/o Storage (Non-Dispatchable) – Dish/Engine
National Renewable Energy Laboratory 3 Innovation for Our Energy Future Parabolic Trough
www.centuryinventions.com
National Renewable Energy Laboratory 4 Innovation for Our Energy Future Linear Fresnel systems
Eck, et al., SolarPACES 2009, Berlin, Germany
National Renewable Energy Laboratory 5 Innovation for Our Energy Future Parabolic Trough Power Plant w/ 2-Tank Indirect Molten Salt Thermal Storage
Trough Field 390°C
Salt Storage Tanks
National Renewable Energy Laboratory 6 Innovation for Our Energy Future Power Tower (Central Receiver)
Different design approaches:
• Direct Steam Generation – Abengoa PS10 (Spain) – Abengoa PS20 (Spain) – BrightSource (USA/Israel) – eSolar (USA)
• Molten Salt – Solar Two (USA demo) – SolarReserve (USA)
• Air Receiver • Jülich (Germany)
National Renewable Energy Laboratory 7 Innovation for Our Energy Future Molten Salt Power Towers
Ability to store hot salt allows molten salt Towers to run at high capacity factors.
565°C 288°C Hot Salt Cold Salt
Steam Generator Heliostat Field
Conventional Condenser steam turbine & generator
National Renewable Energy Laboratory 8 Innovation for Our Energy Future Dish Systems
Dish/Stirling: Pre-commercial, pilot-scale deployments
Concentrating PV: Commercial and pre- commercial pilot-scale deployments
• Modular (3-25kW)
• High solar-to-electric efficiency
• Capacity factors limited to <25% due to lack of storage capability
National Renewable Energy Laboratory 9 Innovation for Our Energy Future Outline
• Technology Overview − Parabolic Troughs − Linear Fresnel − Power Towers − Dish / Engine Systems • CSP Siting, Integration and Markets • Projects • Research & Development Focus
National Renewable Energy Laboratory 10 Innovation for Our Energy Future Solar Resource Screening
All Solar Resources 1. Start with direct normal irradiance (DNI) estimates derived from satellite data.
2. Exclude locations with less than minimum DNI threshold (~6.75 kWh/m2/day)
3. Exclude culturally and environmentally sensitive lands, urban areas, lakes and rivers.
4. Exclude land with greater than 1% to 3% average land slope.
5. Exclude areas of less than 1 km2 Locations best for 6. Site near load centers and transmission Development corridors
National Renewable Energy Laboratory 11 Innovation for Our Energy Future Site filtering example - USA
Solar > 6.75 kWh/m2/day
Land Exclusions
Slope & Area Exclusions
National Renewable Energy Laboratory 12 Innovation for Our Energy Future CSP Resource Potential - USA
USA Total CSP Potential 18000 Assumptions : 16000 14000 • Solar Resource 6.75kWh/m2/day • Land use 5 acre/MW 12000 • Land slope < 1% 10000 • Capacity factor 27% 8000 • Water, urban areas, and 6000 environmentally sensitive lands 4000 excluded 2000 0 Land Capacity Energy (thousand (GW) (TWh) km2)
National Renewable Energy Laboratory 13 Innovation for Our Energy Future Solar Resource – South America
National Renewable Energy Laboratory 14 Innovation for Our Energy Future CSP Integration Advantages
• Match load profile • Thermal inertia – Passing clouds have minor effect – Output exhibits slow ramp rates • Thermal energy storage − Can provide power after sunset − Dispatchable • Can be hybridized with fossil-backup or integrated into fossil power plants
National Renewable Energy Laboratory 15 Innovation for Our Energy Future Thermal inertia avoids rapid power changes
Comparison of power output from large CSP and PV plants located within 50 km of each other.
Mehos, et al., IEEE Power & Energy Magazine, May/June 2009.
16 Thermal Storage - a key CSP advantage
Solar Resource Load • Unlike Wind and PV, CSP can store thermal energy for later use. • Simple thermal storage makes CSP power dispatchable
Generation w/ Storage
Hour of Day Thermal storage tanks at Andasol 1
National Renewable Energy Laboratory 17 Innovation for Our Energy Future CSP integration Challenges
• Cost higher than coal, natural gas, or wind • Economics favor large installations (high capital cost) • Land use & impact – 5-10 acres required per MWe – Land typically cleared and graded – Impact minimized by locating plants on previously disturbed lands • Water consumption – Approximately 3.0 m3 per MWh for wet-cooled plant – Air-cooled plants use 90% less water, but cost more and run at lower efficiency during hot days – Dish/Engine systems use water for mirror cleaning only • Transmission required
National Renewable Energy Laboratory 18 Innovation for Our Energy Future CSP Costs - Troughs
Today’s costs are 0.18 0.12 Technology Cost in 2007 >16¢/kWh due to higher ~$0.16/kWh (nominal) 0.11 0.16 material costs (e.g., steel, 0.10 0.14 nitrate salt) 0.09 0.12 0.08 Costs for Tower and Dish 0.07 0.10 systems will be defined 0.06 0.08 when commercial 2015 Goal 0.05 ~$0.10/kWh systems are built
0.06 Assumes: 0.04 Nominal LCOE ($/kwh) LCOE Nominal - Trough Technology w ith 6 hours of TES (2005$/kwh) LCOE Real 0.03 0.04 - IPP Financing; 30-year PPA Cost Reductions - California Property Tax exemption 0.02 0.02 - Includes scale-up, R&D, learning effects anticipated via 0.01 - Barstow , California site • R&D 0.00 0.00 0 1000 2000 3000 4000 • Deployment Cumulative New Capacity by 2015 (MW) • Plant Size National Renewable Energy Laboratory 19 Innovation for Our Energy Future Source: WGA Solar Task Force Summary Report, includes 30% federal Investment Tax Credit System Modeling: Download at http://www.nrel.gov/analysis/sam Solar Advisor Model (SAM) • Models solar performance, cost, finance, and incentives • Performance models include CSP and PV • Financial models include utility (IPP, IOU), commercial, and residential finance
National Renewable Energy Laboratory 20 Innovation for Our Energy Future Outline
• Technology Overview − Parabolic Troughs − Linear Fresnel − Power Towers − Dish / Engine Systems • CSP Siting, Integration and Markets • Projects • Research & Development Focus
National Renewable Energy Laboratory 21 Innovation for Our Energy Future 354 MW Luz Solar Electric Generating Systems Nine “SEGS” Plants built 1984-1991 (California, USA)
National Renewable Energy Laboratory 22 Innovation for Our Energy Future 64 MW Acciona Nevada Solar One (2007) Nevada, USA
National Renewable Energy Laboratory 23 Innovation for Our Energy Future 50 MW Andasol One and Two with Storage (2009) Andalucía, Spain
National Renewable Energy Laboratory 24 Innovation for Our Energy Future Abengoa Power Towers and Trough Plants Seville, Spain
National Renewable Energy Laboratory 25 Innovation for Our Energy Future Stirling Energy Systems 25kW Prototypes New Mexico, USA
National Renewable Energy Laboratory 26 Innovation for Our Energy Future Ausra 5 MW Linear Fresnel demo California, USA
National Renewable Energy Laboratory 27 Innovation for Our Energy Future Power Tower Pilot Plants
5 MWe eSolar California, USA
6 MWthermal BrightSource Negev Desert, Israel
National Renewable Energy Laboratory 28 Innovation for Our Energy Future CSP Projects in the US
For projects list go to www.seia.org and http://nreldev.nrel.gov/csp/solarpaces/
National Renewable Energy Laboratory 29 Innovation for Our Energy Future Research & Development Focus
• Thermal energy storage systems and materials • Direct steam generation • Collector/reflector performance and durability • Stirling engine design for manufacturing • Resource assessment and forecasting • Receiver performance • Heliostat control
National Renewable Energy Laboratory 30 Innovation for Our Energy Future CSP Summary
• Parabolic Trough CSP plants are commercial technology with a >20- year operating history providing intermediate and peak power. • Without government incentives, CSP costs are still 2x higher than conventional power generators. New Trough, Power Tower, and Dish/Stirling designs offer cost reduction potential. • CSP plants with thermal storage can provide power after sunset while increasing the value of power delivered and promoting grid stability. • The solar resource is immense, with prime CSP locations in the USA, Australia, Spain, North Africa, and India. • Primary environmental impacts are land usage and water consumption (for wet-cooled plants). Access to transmission lines is required. • CSP plants are being planned and built in USA, Spain, and other locations around the world.
National Renewable Energy Laboratory 31 Innovation for Our Energy Future Closing thoughts…
Solar Power has the greatest potential of any renewable energy source.
PV and CSP are still expensive compared with fossil-fired generators, but prices have dropped and are expected to fall further.
With thermal energy storage and conventional turbines, CSP is relatively easy to integrate into the electric grid.
National Renewable Energy Laboratory 32 Innovation for Our Energy Future