Testing Of Pre-Assembled Solar Domestic Hot Water Systems And Heat Storages
Wolfgang Striewe*, Jan Steinmetz, Thomas Biel, Daniel Volker, Korbinian Kramer, Stefan Mehnert, Matthias Rommel Fraunhofer Institute for Solar Energy Systems ISE, Heidenhofstrahe 2, D-79110 Freiburg* Corresponding Author, wolfgang. striewe@ise. fraunhofer. …
The neural networks
To model the collector array as simply as possible, a very small network is used. Using a unique non linear neuron on the hidden layer and a linear output neuron …
All glass ETCs
It can be seen from Figure 4 that the thermal performance of the all glass ETC 5 is always larger than that of the reference collector, ETC 4, simply due …
Conclusions and further perspectives
The development and set-up of a mobile, stand-alone test facility for solar thermal collectors and systems based on a 20 foot office container as well as the test facilities required …
Quantification of the impact resistance of solar thermal collectors and. photovoltaic-modules against severe hailstorms
Stefan Mehnert*, Matthias Rommel, Stefan Brachmann, Joseph Steinhart, Thorsten Siems,Anne-Marie Behringer, Georg Mulhofer, Korbinian Kramer, Johannes Scherer Fraunhofer Institute for Solar Energy Systems ISE, Heidenhofstrafle 2, D-79110 Freiburg, GermanyCorresponding Author, …
. Array Layout and Absorber Orientation
The new ICPC evacuated tubes were fabricated with two absorber orientations, one with a vertical absorber fin and one with a horizontal fin. A cross-section of the collector tube illustrating …
The Portuguese Building Thermal Regulations on solar collectors
The new Thermal Regulations are applied to the all new residential and to some office buildings. Some cases of important retrofit work are also enclosed. The regulations are applied separately …
Function Control without Heat Measurements (FUKS)
In the second half of the 90’s the FUKS-approach (function control without heat measurements) was developed in Germany as a cheap function control (<100€) [3]. This approach applies algorithms to …
Two-Axis Tracker
PSE has been developing uniaxial and biaxial trackers for several years, for use in linear concentrating Fresnel collectors [2], heliostats, measurement of solar thermal collectors, etc. The mechanical design of …
Determination of the Degree of Mixing
Before the start of test, mix the water in the storage tank by using a small pump to circulate the water from the top to the bottom of the store. …
Selection of the best fitting surface
To be able to calculate the thermal performance of one specific thermosiphon DHW system, it is necessary to identify the surface that describes the thermal behaviour of the system in …
Development of new system testing facilities
Different SDHW systems (thermosiphon systems, integrated collector-storage systems and forced - circulation systems) have been tested at Fraunhofer ISE since 1997 The testing facilities for preassembled systems have now been …
The FDS procedure
The kernel of the system is the neural networks. So, it is necessary to consider a first step to train the networks. This period should be as short as possible …
Double glass ETC with heat pipe
In phases 2 and 3, the thermal performance of the ETC 6 was measured. It is can be seen from Fig. 4 that the performance ratio of ETC 6/ETC 4 …
Ageing Performance of Collector Glazing Materials — Results from
20 Years of Outdoor Weathering F. Ruesch*, S. Brunold Institut fuer Solarenergie SPF, HSR University of Applied Sciences, Oberseestrasse 10, CH-8640 Rapperswil. * Corresponding Author, florian. ruesch@solarenergv. chAbstract The outdoor …
Frequency of severe hailstorms in Europe
Generally we talk about hail from a hailstone size larger than 0.5 cm. Smaller sizes are denoted as graupel or soft hail. However, the probability that hailstone sizes smaller than …
Evacuated Tube Reliability
After a year of operation several distinct patterns in the development of cracks in the evacuated tubes emerged. One of these involved the production sequence or, equivalently, the fin orientation …
Portuguese buildings market on solar collectors
In the 80s decade there was made an important investment in solar collector technology in Portugal but some problems related with an insufficient developed technology and inexperienced installer firms have …
Spectral method (SPM)
The spectral method is based on analyzing the transient temperature changes in the collector circuit after the pump is started [5; 6]. Temperature signals on a secondly basis are transformed …
Solar simulator with artificial cold sky
Figure 4: Tracker under the solar simulator during indoor testing The solar simulator’s lamp field consists of sixteen 1500 W metal halide lamps. In addition to the vertical and tilt …
Performance investigations of differently designed heat-pipe. evacuated tubular collectors in the Artic climate
J. Dragsted1*, J. Fan1 & S. Furbo1 1 Department of Civil Engineering, Technical University of Denmark, Brovej, Building 118, 2800 Kgs. Lyngby, Denmark Janne Dragsted, iaa@byg. dtu. dk Abstract Evacuated …
Implementing the mathematical model into a computer program
In order to reduce the time necessary to identify the best fitting surface and to ensure that the method is applied by all users in the same way the mathematical …
System Families
It is possible within the Solar Keymark scheme rules to test and certify thermal solar collectors as families. This reduces the effort for the testing by far. A similar procedure …
Update on European Standards for Thermal Solar Systems. and Components and on Solar Keymark Certification
H. Drtick*, H. Mtiller-Steinhagen University of Stuttgart, Institute for Thermodynamics and Thermal Engineering (ITW) Pfaffenwaldring 6, 70550 Stuttgart, Germany Tel.: +49 711 / 685-63553, Fax: +49 711 / 685-63503 Corresponding …
Direct flow ETC
4. Conclusion Side-by-side tests of seven differently designed evacuated tubular collectors were carried out in an outdoor test facility. The observations from the measurements show that the direct flow ETC …
Material selection and exposure
After a market analysis, which included all major distributors, a selection of 58 collector glazing types were chosen in the beginning of this long-term investigation (1984). An overview of tested …
Increase of the loss potential caused by severe hailstorms
The challenge of the estimation of the real existing loss potential at solar energy systems caused by severe hailstorms is given in the combination of high accounts on, at present, …
Vertical fin ray trace analysis
The optical efficiency based on a surface reflectance measurements is 0.94, the gap between reflective surface and the absorber fin is 4 mm and the absorptance is 0.95. The first …
Initial impacts of the implementation of the regulations on solar collectors
2.1. The education and training for project design professionals Portuguese Civil Engineers are the legal responsible professionals for elaborate the water supply design projects. Until now they had to deal …
Input-Output Controller (IOC)
The Input-Output Controller is a simulation based failure detection method available on the market since 2007. The first variant of the method monitors only the energy yields in the solar …
Conclusion: Summary and Future Perspectives
A complete research and testing laboratory for scientific research in the field of solar energy utilization was built near Tripoli, Libya, for the CSES of the National Office for Research …
Model description
1.1. Validated models Validated models are used for the parameter analyses [4]. The validation was carried out in 2007 with measurement data from the four different evacuated tubular solar collectors …
Validation of the mathematical model
For the validation of the developed mathematical model, the results of the DST tests of one thermosiphon system product line are used. Systems of this product line with different collector …
Engineering and set-up of a new testing facility for solar thermal systems
At the Fraunhofer ISE a testing facility for solar domestic hot water systems (thermosiphon systems, systems with forced circulation, integral collector-storage systems) and heat storages is already in operation since …
European standards for solar thermal products in general
In 2000 and 2001 the first edition of the European standards for solar thermal systems and components was issued, and started to replace all related national standards /1/. The three …
