SunMaxx-20 Evacuated Tube Solar Collectors recently concluded a rigorous, independent testing process by the SRCC (Solar Ratings and Certification Corporation) at the FSEC facility in Southern Florida. At the beginning of April 2008, SunMaxx received the testing report from the SRCC, listing the performance of the SunMaxx-20 Evacuated Tube Solar Collectors:
SunMaxx Collector Thermal Performance Rating
Megajoules Per Panel Per Day |
Category
(Ti - Ta) |
Clear Day
23 MJ/m2 * d |
Mildly Cloudy
17 MJ/m2 * d |
Cloudy Day
11 MJ/m2 * d |
A (-5 C) |
33 |
25 |
17 |
B (5 C) |
32 |
24 |
16 |
C (20 C) |
30 |
22 |
13 |
D (50 C) |
25 |
17 |
9 |
E (80 C) |
19 |
11 |
4 |
|
|
|
|
Thousands of BTU Per Panel Per Day |
Category
(Ti - Ta) |
Clear Day
2000 BTU/ft2 * d |
Mildly Cloudy
1500 BTU/ft2 * d |
Cloudy Day
1000 BTU/ft2 * d |
A (-9 F) |
31 |
23 |
16 |
B (9 F) |
30 |
22 |
15 |
C (36 F) |
28 |
20 |
13 |
D (90 F) |
23 |
16 |
8 |
E (144 F) |
18 |
10 |
3 |
- A: Pool Heating (warm climate)
- B: Pool Heating (cool climate)
- C: Water Heating (warm climate)
- D: Water Heating (cool climate)
- E: Air Conditioning
Pressure Drop Ratings
Flow |
∆ P |
ml/s |
GPM |
Pa |
in H2O |
20 |
0.32 |
774 |
3.11 |
50 |
0.79 |
3806 |
15.28 |
80 |
1.27 |
9083 |
36.47 |
For standardization purposes in comparing solar collectors with one another, the SRCC, and other comparison agencies use the C Value (Water Heating in Warm Climates) at Clear Day Conditions to provide an accurate distinction between how well two different collectors operate under the same conditions.
Note: The SRCC efficiency ratings are based off of gross area and not aperture area, which yields a lower efficiency rating when compared to the actually aperture area.
SRCC:
Fr (tau alpha) coefficient: .371
Fr UL coefficient: -1.32 w/m3*C
Temperature coefficient for Fr UL: .8252
European Standards: Solar KeyMark(click here to view test report)
Fr (tau alpha) coefficient: .734
Fr UL coefficient: 1.529 W/m2K
Temperature coefficient for Fr UL: 0.0166 W/m2K2
Note: Collector efficiency ratings are based off of actual aperture area. To determine the aperture area of each collector multiple the value of 1sq ft (for each tube). Example: Sunmaxx-20 tube has an aperture area of 20sq ft.
