1 Summary
1.1 Preliminary remark to the efficinency meassurement
The tests on SPA-58-1800-18-C have been passed according to EN 12975-1,2:2006.
This report is also valid for the collectors SPA-58/1800-20-C, SPA-58/1800-24-C and SPA-58/1800-30-C. The constructive layout of this collectors is identically to the test collector. Only the number of tubes vary. As the collector is constructed without a reflector or another defined reflecting backside, the effincy messurements were performed by using a tarpaulin with a defined emission coefficient of 83 %. This corresponds to the emission coefficients of commen rooftile. All test results were taken from KTB 2006-12 from 15th of August 2006.
This report is a translation to english.
1.2 Boundary conditions for the collector efficiency parameter determination
Test method: outdoor, steady state
Latitude: 48.0o
Longitude: 7.8o
Collector tilt: tracked between 40oand 50o
Collector azimuth: tracked
Mean irradiation : 986 W/m2
Mean wind speed: 3 m/s
Mean flow rate: 124 kg/h
Kind of fluid: water
Period: July 2006
1.3 Collector efficiency parameters determined
The calculated parameters rely on following areas:
aperture area of 1.706 m2: absorber area of 1.451 m2:
η0a = 0.573 η0A = 0.674
a1a = 2.085 W/m2K a1A = 2.452 W/m2K
a2a = 0.0083 W/m2K2 a2A = 0.0098 W/m2K2
Power output per collector unit [W]:
tm-ta [K] 400 [W/m2] 700 [W/m2] 1000 [W/m2]
10 354 647 941
30 272 565 858
50 178 471 764
1.4 Incidence angle modifier - IAM (measured at the outdoor test facility (tracker))
Test method: outdoor
transversal: dynamic
longitudinal: steady state
Latitude: 48.0o
Longitude: 7.8o
Collector tilt: tracked
Collector azimuth: tracked
IAM at : 0o 10o 20o 30o 40o 50o 60o 70o 73o 80o 90o
transversal: 1.00 1.00 1.02 1.10 1.22 1.37 1.42 1.27 1.42 0.93 0.05
longitudinal: 1.00 1.00 1.00 1.00 1.00 0.96 0.91 0.79 0.94 0.53 0.00
Table 1: Measured (bold) and calculated IAM data for SPA-58-1800-18-C
1.5 Effective thermal capacity of the collector
Effective thermal capacity: 25.90 kJ/K
The effective thermal capacity per sqaure meter is: 15.18 kJ/K m2
1.6 Tests on efficiency
Test Date Result
Date of delivery: 04.05.2006
Determination of
collector parameters July 2006 passed
Determination of IAM July 2006 passed
Effective thermal capacity calculated performed
1.7 Summary statement
No problems or distinctive observations occured during the measurements.
2 Test Center
Test Center for Thermal Solar Systems of Fraunhofer ISE
Heidenhofstrae 2, D-79110 Freiburg
Tel.: +49-761-4588-5354 or -5141; Fax.: +49-761-4588-9354
E-mail: arim.schaefer@ise.fraunhofer.de; rommel@ise.fraunhofer.de
Internet: http://www.kollektortest.de
3 Orderer,Expeller, Manufacturer
Orderer Sunpower Solar Water Heater Co.,Ltd
69 South Airport Road Luoxi Town Changzhou
Tel: 0086 519 508 3 201
Fax: 0086 519 508 3 220
Expeller and Manufacturer: see orderer
4 Description of the Collector
4.1 Collector
(MS) = Manufacturer Specification
Type: vacuum tube collector with heat
pipe conception
Brand name: SPA-58-1800-18-C
Serial no.: 1-180-18-0001
Year of production: 2006
Number of test collectors: 1
Collector reference no.: 2 KT 54 002 052006
Total area: 2.100 m * 1.487 m = 3.123 m2
(total dimensions without fittings)
Aperture area: 1.706 m2
(projected area of the inner diameter
of the cover tube)
Absorber area: 1.451 m2 (MS)
(projected area of outer diameter of
absorber tubes)
Material of the cover tube: Borosilcat glas (MS)
Transmission of the cover tube: n/a (MS)
Outer diameter of the cover tube: 58 mm (MS)
Thickness of the cover tube: 1.5 mm (MS)
Outer diameter of the inner tube 47 mm (MS)
Thickness of the inner tube: 1.5 mm (MS)
Length of the tubes: 1775 mm (MS)
Distance from tube to tube: 80 mm (MS)
Number of tubes: 18 (MS)
Weight empty: 58 kg (MS)
Volume of the fluid: 1.1 l (MS)
Heat transfer fluid: antifreeze persistent to hight temperatures (MS)
