This presentation was given at Solar Concentrator Conference in Sept. 2008, Palm Desert, CA. It discussed all aspects of solar plant design, specifications, installation, and energy production for SolFocus\' 0.5MW CPV plants in Spain.

1. Energy Production of CPV Power Plants
at ISFOC
Warren Nishikawa
warren_nishikawa@solfocus.com
warren nishikawa@solfocus com
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

2. Outline
Project and Site Overview
j
CPV Systems Design
CPV Power Ratings & Normalizing Methods
Energy Production: Predicted vs. Actual
Summary
2
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

3. 0.5 MW Installation at ISFOC
ISFOC Headquarters at Puertollano
ISFOC: World-Recognized
Concentrating Photovoltaic
(CPV) Technology Site
• Goal of industrializing CPV
technology
• 3 MW, 7 CPV technologies
SolFocus CPV Plants
• Site #1: 0.2 MWac at Puertollano
• Site #2: 0.3 MWac t Almoguera
Sit #2 0 3 MW at Al
• 1st Company to Complete CPV
Plants, High Feed-In Tariffs
• Grid Connected
3
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

4. Site Design
g
Site #1: Puertollano Site #2: Almoguera
33 Systems 54 Systems
200 kWac 300 kWac
• <4% Shading • <2% Shading
• 20 m EW/15 m NS • 20 m EW/17 m NS
• 0.9 Hectares • 2.1 Hectares
4
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

5. Site #1: Puertollano
Grid-Connected
Grid Connected September 2008
5
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

6. Site #1: Puertollano
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© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

7. SF-
SF-1000 Concentrator
Power Unit CPV Panel
500x Concentrator Optics 210 W Panel
• All glass components • True, on-sun rating
• 35% efficiency 3J cell • >23% active area efficiency
1.1 m
• 85% optical efficiency
• +/- 1 degree acceptance angle
1.3 m
1
7
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

8. SF-
SF-1000S System
y
6.7 m
6.9 m
6.15 kWp, 30 Panels
46 m2 Aperture
0.1 Degree Pointing Accuracy
g g y
8
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

9. System Peak Power
y
Puertollano Array DC Peak Power
7000
Specification*:
S ifi ti *
6500
• Array: 6.15 kWp
6000
Measured**:
er (Watts DC)
)
• Array: 6.20 kWp 5500
• 2% Std. Dev. 5000
Powe
4500
*IEC CPV Test Conditions:
850 W/m2, 20°C Ambient
4000
**Average 33 Systems
3500
3000
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
1.10
1.11
1.12
1.13
1.14
1.15
1.16
1.17
2.10
2.11
2.12
2.13
2.14
2.15
2.16
Array #
Array #
9
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

10. Rated Power
Normalized to Concentrator Standard Test Conditions
(CSTC): 850 W/m2 DNI, 20°C Ambient Temp.
Power Normalized at DNI Test Conditions Power Normalized at Temperature Test Conditions
7000
7000
6750
6750
6500
6500
C (Normalized)
Power DC (Normalized)
6250
6250
6000
6000
5750
5750
Power DC
5500
5500
5250
5250
5000
5000
50 60 70 80
700 800 900 1000
Backpan Temperature
Backpan Temperature
DNI (W/m^2)
DNI (W/ ^2)
Empirical Method Theorectical Method
Emprical Method Theorectical Method
Empirical: P em p = (1+(Tme as –TC STC ) ) * dP/dT * P m ea s * (B CS TC/B me as )
0 . 0257 × ( T CSTC − T meas ) ⎡ ⎛ (I SC , meas − I SC , CSTC ) ⎞ ⎤ + [N ( E ⎛ ⎞
] T
⎢ ln ⎜ ⎟ + E g 2 + E g 3 ) − V oc , meas ⎜ 1 − CSTC ⎟
Δ Vi = N ⎟⎥
Theoretical: ⎜ ⎟
⎜ g1
⎢⎝ ⎠⎥ ⎝ ⎠
297 I SC , meas T meas
⎣ ⎦
Results: Only 1.3% Difference
10
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

11. Temperature Performance
p
80
Array Power
Coefficient: 75
ure [C]
-0.17%/°C 70
Typical Si Panels:
n Temperatu
65
-0.48%/°C 60
3x Better Than Si 55
Backpan
Technology y = ‐1.260x + 645.2
50
Best Performance at
45
High Temperatures
g p
445 450 455 460 465 470
Array Voc (V)
Array Voltage Coefficient: -1.26V/°C
11
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

12. System Specifications
30 Panels Max Output 6.3kW
6 3kW
Mismatch -2%
Misalignment -1%
DC Losses -3%
DC Power Spec 6.15kW
Inverter -3%
3%
Dirt -2%
Downtime -1%
AC Losses -6%
6%
AC Power Spec 5.78kW
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

13. Energy Production Calculations
Site #1: Site #2:
Puertollano Almoguera
DNI (kWh/m2)* 5.1 5.4
kWh/kWp 2059 2180
# Systems 33 54
Rated DC Capacity (kWp) 203 332
Rated AC Capacity (kWac) 191 312
Annual Production (MWh) 416 728
*Solar Resources:
Meteonorm, SWERA-NASA
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

14. Annual Energy Production
gy
800
700
600
500
MWh
400
300
200
100
0
Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec
Site #2 Cumul 41 88 151 211 277 362 454 539 607 655 693 728
Site #1 Cumul 23 50 85 123 161 212 266 316 352 379 397 416
Site #1 Monthly
Site #1 Monthly 23 28 34 38 38 51 54 50 36 27 18 19
Site #2 Monthly 41 46 64 59 67 84 93 85 68 48 38 35
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

15. Puertollano Performance
250000 125%
Puertollano: November 10, 2008
200000 100%
150000 75%
Total for 33 poles
100000 50%
Norm. to 850 DNI
Percent of rating
50000 25%
00000 0%
10:00
10:20
10:40
11:00
11:20
11:40
12:00
12:20
12:40
13:00
13:20
13:40
14:00
14:20
14:40
15:00
15:20
15:40
16:00
16:20
16:40
17:00
8:00
8:20
8:40
9:00
9:20
9:40
15
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

16. Summary
y
0.5 MWac Installed at ISFOC
Systems Rated at Concentrator Standard Test
Conditions (CSTC) – True, On-Sun Performance
( )
Systems Measured Above Specification for DC
Peak Power
Beginning to Demonstrate Energy Production
>95% of Predicted Output
16
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)

17. Other Potential CPV Benefits?
Tested Against Tornados Hybrid CPV-Wind
CPV Wind
*Almoguera Site, August 2008
17
© SolFocus, Inc. 2008
Presented : International Conference on Solar Concentrators for the Generation of Electricity (ICSC – 5), November 16‐19, 2008, Palm Desert, CA USA (www.icsc5.com)