Page 217 - ISES SWC50

8.10 ISES Institute Member- SPF Insitute for Solar Technology

The history of the SPF Institute for Solar Technology (by Stefan Brunold)
The oil crisis at the beginning of the 1970s leads to a first boom in solar thermal energy not only in Switzerland.
This triggers numerous developments of materials, components and concepts for solar thermal systems, some
of them serious, some exotic. In this pioneering phase that lasts until the 1980s, numerous manufacturers,
dealers and fitters appear on the market, with products of partly questionable quality. As a result, the Federal
Office of Energy Industry, BEW (now Swiss Federal Office of Energy, SFOE) advertises the research project
‘Service life and operational safety of solar systems’. Ueli Frei, a recent graduate from the engineering school
‘Interkantonales Technikum Rapperswil, ITR’, gets the contract, thus laying the foundations of the Swiss
Institute for Solar Technology SPF in 1981.

From the very beginning, SPF establishes close contacts with industry and commerce, but also with other
organizations worldwide. Thus, already in 1983, the first highly acclaimed publication with the topic ‘Durability
of Absorber Coatings’ is published together with the Paul-Scherrer-Institute PSI (back then Institute for
Reactor Safety EIR), which at that time is still active in the field of solar thermal research. Soon thereafter,
increasing emphasis is also placed on international cooperation within the framework of the International
Energy Agency’s Solar Heating and Cooling Program (IEA-SHCP), resulting in new impulses and productive
collaborations with research institutions worldwide. SPF’s participation in international conferences and the
number of scientific publications is steadily increasing, culminating in the so-called ‘red series booklets’, which
becomes extremely popular in the German-speaking world and are sold in several editions of up to two
thousand copies between 1984 and 1986. This five-part series summarizes the results of the research project
‘Service life and operational safety of solar systems’.

After the PSI’s research goals in the field of solar energy utilization are redefined in 1986 and, as a consequence,
their work on thermal collectors is discontinued, the BEW comes to the far-reaching decision to expand SPF
into the national competence center for solar thermal energy. As a result, SPF continues to develop rapidly in
terms of staff and structure. The previously used static racks for the solar collectors in test are replaced by a
series of dual-axis trackers. Placed on the roof of the ITR laboratory building, these trackers are at that time
the core of the new infrastructure. The successful setup of the laboratory roof is the occasion for the formal
inauguration of the SPF on May 16, 1990.

In the following years, SPF develops numerous test methods and certificates, which support the solar industry
in the development and marketing of new products. These include the SPF quality label for solar collectors, the
SPF Solar Glass Certificate, test methods for hydraulic connectors, for solders and thermal insulation, just to
name a few. In international cooperation, a standard for accelerated aging testing of solar absorber coatings is
being launched which enjoys worldwide recognition under the name ‘Task 10 - Test’. The ‘Concise Cycle Test
Method’ (CCT), which is now frequently copied, is developed in order to determine the performance of solar
combi-systems within the shortest possible time.

Moreover, SPF also sets new standards in product development. From 1990 on SPF starts developing the
simulation software Polysun. In 2007, version 4.0 goes commercial by the SPF spin-off ‘Vela Solaris AG’.
Through continuous further development, Polysun is now much more than ‘just solar software’. With the
‘Solkit’, SPF introduced in 1995 one of the first solar compact systems for domestic hot water production.
Designed as a kit, production and installation costs are reduced and faults during the installation can be
prevented. In 1999, the Swiss Electrotechnical Association SEV awards its Innovation Prize to two SPF
researchers for a new type of solar absorber layer developed in collaboration with the University of Basel.
The coating is produced in a resources saving vacuum process that is patented worldwide.
Because of the restructuring of the Swiss educational landscape, in 1997 ITR became HSR (Hochschule für
Technik Rapperswil), a part of the University of Applied Sciences Eastern Switzerland FHO. Three years later,
the HSR begins implementing the Bologna reform. In 2001, the SPF, grown to 20 employees and independent
at that time, becomes an institute of HSR and thus part of FHO. This step supports the integration of solar
technology into the education of future engineers at HSR. The number of bachelor and master theses

ISES SWC50 - The Century of Solar-Stories and Visions | 199