1. Solar Energy Part 4: Trombe Walls and Concentrators San Jose State University FX Rongère February 2008

2. Trombe wall Solar radiation is used to heat the air in a channel along the walls

3. Energy transfer          

4. Solar Wall Perforation in a Solar Wall panel Source: SolarWall

5. Solar Wall

6. The Solar wall integrated in the building architecture

7. Solar Wall Sizing of the wall

8. Solar Wall Efficiency Flate plate Collector Absorber Solar Wall

9. Solarwall applied to walnut drying 9,300 ft2 of Solarwall cladding on the roof of a new drying facility at Keyawa Orchards, Inc. 3 months of operation per year Savings 14,000 Therm per year 65,000 cfm at 110 o F 5: Keyawa orchads, Inc. drying process. Solarwall fact sheet

10. Concentrator Parabolic reflective surface with the collector at its focal point. The concentrator tracks the sun

11. Application: SEGS in Mojave desert Built between 1984 and 1991 350 MWe of peak power 1,000,000 mirrors (6 km 2 ) x30-60 concentration factor Oil heated to 390 o C (735 o F) Maximum conversion rate: 20%

12. Steam cycle of SEGS

13. Direct Steam Generation Ausra:

14. Ausra

15. Maximal conversion rate Carnot efficiency: It represents the greatest possible conversion rate of a generator using a two temperature cycle The conversion rate is then limited by the hot source temperature

16. Carnot Cycle Isotherm heating (A->B) and cooling (C->D) Energy balance Entropy balance

17. Carnot Cycle Isentropic expansion (B->C) and compression (D->A) Energy balance Entropy balance

18. Heliostats Solar-Two built in 1995 10 MWe of peak power 1,926 mirors (82,750 m 2 ) Storage: Salt heated at 565 o C (1,050 o F)

19. Solar 2

20. E-Solar Each tower is 25 MWe

21. Rankine steam Cycle 374 o C, 221 Bar

22. Stirling Engine Stirling Energy: 25 kW per dish Infinia: 3kW Conversion rate: 30%

23. Stirling Engine The working gas is heated at a constant volume The working gas expands at a constant temperature The gas is transferred to the cool cylinder + The working gas is cooled at constant volume The working gas contracts at a constant temperature The gas is transferred to the hot cylinder

24. Some companies Companies to follow www.Solarwall.com www.Ausra.com www.Brightsourceenergy.com www.Stirlingenergy.com www.Solel.com www.esolar.com www.infiniacorp.com The Ausra concentrator