Comprehensive Stress Tests under Different Climates
On 23 November 2012, the Fraunhofer Institute for Solar
thermal collectors into operation. With this test stand, the
scientists aim to simulate mechanical loads under extreme
climate conditions e. g. wind or snow loads, analyzing their
effects on the solar collectors. Fraunhofer ISE and PSE AG,
both located in Freiburg, jointly developed this special
mechanical load test stand housed in a climate chamber. The
test results shall serve as input for new test procedures and
improve the quality and safety standards for solar thermal
collectors over the long term. Now with the newly created
experimental possibilities, new materials, material savings
and optimizations can be analyzed under real-like conditions
in order to save costs on collectors and mounting elements.
With the new test stand, Fraunhofer ISE is able to investigate
complex questions about the mechanical stability of solar
thermal collectors, including their mounting system for roof
and façade applications. The test stand can handle collectors
up to a maximum of nine square meters and loads up to
seven tons push and pull. Another notable feature is that the
mechanical load tests can be carried out under extreme
temperatures from -40 °C to +60 °C. Additionally, it is
possible for the first time to simulate cyclical as well as
asymmetric loads, like varying amounts of accumulated snow
on the collector, and also how the loads are realistically
created through the piling up of snow and ice." We see a
large potential in the new system," says Korbinian Kramer,
Group Leader of Test Center and Quality Assurance at
Fraunhofer ISE. "The new test stand enables a more detailed
investigation of the connecting techniques and mounting system under different temperatures and realistic load cases.
This is a decisive advantage over the established test
procedures in which the loads are merely applied
perpendicularly and at room temperature."
During the joint development and the manufacture of the
new test stand by PSE AG, there were many challenges to
overcome. "The requirements for the test stand were very
complex: for example, high flexibility with regard to possible
loads and at the same time very large mechanical loads. We
employed a lot of technical ingenuity in order to implement
all the degrees of freedom necessary for the load tests,"
explains Frank Luginsland, Department Head of Technology
at PSE AG.
Based on a detailed analysis of the loads, the scientists at
Fraunhofer ISE develop a test method which is generally
applicable for the different types of collector constructions,
compact systems and mountings under different climatic
conditions. In the medium-term, this leads to the further
development and improvement of solar thermal
components. This new test method is offered to
manufacturers who want to verify the safety and quality of
their product with little effort from their side. Through such
tests, both material savings and optimization can be
achieved which lead to reduced costs in the installation of
large solar systems. The work and the test stand are
supported through "MechTest", a project sponsored from
the Federal Ministry for the Environment, Conservation and
Nuclear Safety (BMU).
About Fraunhofer ISE
With a staff of 1200, the Fraunhofer Institute for Solar
Energy Systems ISE, based in Freiburg, is the largest solar
energy research institute in Europe. Fraunhofer ISE is
committed to promoting energy supply systems which are
sustainable, economic, safe and socially just. It creates the
technological foundations for supplying energy efficiently
and on an environmentally sound basis in industrialized, threshold and developing countries. To this end, the institute
develops materials, components, systems and processes for a
total of eight different business areas: Energy-Efficient
Buildings, Applied Optics and Functional Surfaces, Solar
Thermal Technology, Silicon Photovoltaics, Photovoltaic
Modules and Systems, Alternative Photovoltaic Technology,
Renewable Power Supply and Hydrogen Technology.
Fraunhofer ISE also has numerous accredited test facilities.
About PSE AG
PSE AG provides highly specialized solar testing systems and
solar consulting expertise to customers around the world.
PSE Solar Test Stands are used by test labs and
manufacturers for performance and durability measurements
and certification to international standards. PSE Solar
Consulting conducts rural electrification consulting and
manages international research projects. PSE Conference
Management organizes major scientific solar conferences.
PSE AG was established in 1999 as a spin-off company of
the Fraunhofer Institute for Solar Energy Systems ISE and
currently has a staff of 65.