1 / 22

Past, Present, and Future of Solar Thermal Generation

Bruce Kelly Abengoa Solar, Incorporated Berkeley, California June 2008. Past, Present, and Future of Solar Thermal Generation. Topics. Solar resource Solar thermal technologies Early projects Current projects Future plans. Solar Resource.

biana
Download Presentation

Past, Present, and Future of Solar Thermal Generation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Bruce Kelly Abengoa Solar, Incorporated Berkeley, California June 2008 Past, Present, and Futureof Solar Thermal Generation

  2. Topics • Solar resource • Solar thermal technologies • Early projects • Current projects • Future plans

  3. Solar Resource • Southwest US, filtered for environmental areas, urban areas, water, and slope < 3% • 9,800 TWhe potential • 3,800 TWhe US energy consumption

  4. Parabolic Trough • Type: Glass mirror; single axis tracking; line focus • Nominal concentration: 80:1 • Heat collection fluid: Synthetic oil • Peak temperature: 393 C

  5. Central Receiver • Type: Glass mirror, two axis tracking, point focus • Nominal concentrations: 600 to 1,200:1 • Heat collection fluids: Steam, air, or nitrate salt • Peak temperatures: 400 to 850 C Photo by Mike Taylor, SEPA

  6. Linear Fresnel • Type: Glass mirror, single axis tracking, line focus • Nominal concentration: ~100:1 • Heat collection fluid: Saturated steam • Peak temperature: ~260 C Photos taken by Mike Taylor, SEPA

  7. Parabolic Trough

  8. Early projects Solar Electric Generating Stations (SEGS) SEGS I and II: 14 and 30 MWe; Daggett SEGS III through VII: 30 MWe; Kramer Junction SEGS VIII and IX: 80 MWe; Harper Lake Financed through very favorable combination of investment tax credits, Standard Offers, and PURPA requirements All are still in operation Parabolic Trough

  9. Current projects Acciona: 64 MWe Nevada Solar One Solar Millennium: 50 MWe AndaSol 1 Nevada Solar One financed through investment tax credit and renewable portfolio standard AndaSol 1 financed through Spanish feed-in tariff at ~$0.40/kWhe Parabolic trough technology investment to date ~$3,000 million Parabolic Trough

  10. Future plans Spain: 50 MWe; limited by tariff structure US: 125 to 250 MWe; economies of scale Advanced collector coolants Direct steam generation, and inorganic nitrate salt mixtures 450 to 500 C collector field temperatures More efficient Rankine cycles Why not yet? → Direct steam generation has complex controls, and salt freezes Parabolic Trough

  11. Central Receiver

  12. Early projects France, Spain, Italy, Japan, and United States 1 to 10 MWe Receiver coolants: Sodium; nitrate salt; compressed air; and water/steam Design point efficiencies were close to, but annual energy efficiencies were well below, predictions Most suffered from lack of operating funds Central Receiver

  13. Current projects Abengoa: PS10 and PS20 US DOE: Solar Two (1999) PS10 and PS20: Saturated steam receivers; high reliability, but below-commercial efficiency Solar Two: Nitrate salt receiver, thermal storage, and steam generator; high efficiency, but poor reliability Technology investment to date ~$1,000 million Central Receiver

  14. Future plans Abengoa: Superheated steam; compressed air; and nitrate salt SolarReserve: Nitrate salt in South Africa and US eSolar: 13 distributed superheated steam receivers; very small heliostats; central 30 MWe Rankine cycle BrightSource: 4 towers; small heliostats; central 100 MWe reheat Rankine cycle Central Receiver

  15. Why not yet? Superheated steam: Moderate annual efficiencies; thermal storage may be impractical Compressed air: Complex receiver; small plant sizes; thermal storage may be impractical Nitrate salt: Less than perfect operating experience; equipment development must occur at commercial scale, with ~$750 million project investment Central Receiver

  16. Performance and Cost • Annual efficiencies, capital costs, operation and maintenance costs, and levelized energy costs • Parabolic trough • Nitrate salt central receiver

  17. Parabolic Trough • Annual solar-to-electric efficiencies • 14 to 16 percent gross • 12 to 14 percent net • Capital cost • ~$4/We without thermal storage; includes project financing, interest during construction, and owner’s costs • ~$5 to $8/We with thermal storage

  18. Parabolic Trough • Operation and maintenance cost • $0.02 to $0.04/kWhe • Levelized energy costs • $0.14 to $18/kWhe with Southwest US direct normal radiation and 30 percent investment tax credit • $0.35 to $0.40/kWhe with southern Spain direct normal radiation and no financial incentives

  19. Salt Central Receiver • Annual solar-to-electric efficiencies • 17 to 19 percent gross • 15 to 17 percent net • Capital cost • ~$4/We with minimum thermal storage; includes project financing, interest during construction, and owner’s costs • ~$7/We with thermal storage at 70 percent annual capacity factor

  20. Salt Central Receiver • Operation and maintenance cost • $0.02 to $0.03/kWhe • Levelized energy cost • For a commercially mature design (which does not yet exist), a nominal 20 percent below that of a parabolic trough project

  21. Future Markets • Capital investment essentially dictated by commodity prices • Energy price parity with natural gas combined cycle plant is unlikely • Solar thermal energy is • Much better matched to utility peak demand than wind • Immune to rapid changes in plant output common with photovoltaic projects

  22. Future Markets • With 30 percent investment tax credit and property tax exemption, solar energy prices are within $0.02 to $0.03/kWhe of market price referant • Renewable portfolio standards, plus a modest carbon tax, should provide a commercial, multi-GWe market for solar thermal projects

More Related