Research institute

Our company, Stroj - energijska tehnika d.o.o., is always looking for new improvements that deliver innovative solutions for individual features of each project and constantly upgrade methodological and technological processes. The driving force of our company is our CEO, Franc Stroj. The beginnings of our development date back to his early teenage years. Even as a primary school student, he had a passion for innovation, and searched unusual solutions, particularly in the areas of water, electricity and heat.

Thousands of small and large heating systems testify to the quality and trust that the users and experts grant this company with a long tradition. Annually, we install approximately 700 SEC, which amounts to 700,000 kWh, and connects them to various heating systems.

In 2007, we have founded our own energy research institute Stroj (ERIS), which operates within the Slovenian Research Agency, under no. 2539, date: 7 March 2007. Within the facilities of our institute, we test and design new products, which enable efficient use of renewable energy resources.

Read more: ekspertiza.pdf.


For three years, our institute ERIS and our company have studied the difference between STROJ flat panel collectors and SEC evacuated tubes. Measurements and comparisons have shown that Stroj collector achieved 35% higher yield compared to the evacuated tubes per gross surface collector area. In sunny winter days, when the temperate has fallen below 0 °C (32 F), the evacuated tubes accumulate frost, which did not melt as the vacuum is an excellent insulator. The collectors refused to function until the outside temperature increased.

In winter, STROJ solar collector thaws even at minimal solar radiation during winter, as the metal edge is warmed by the sun.

The comparisons are substantiated and proven in practical situations, which can be found at the company's headquarters in Dvorska vas.