Low degradation of a-Si solar panels of the building integrated PV power plant in Prague historical area

M. Libra¹*, T. Olšan¹, V. Avramov² and V. Poulek¹

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Physics, Kamycka 129, CZ 16521 Prague, Czech Republic
²ENESA, joint-stock company, Prague, Czech Republic
*Correspondence: libra@tf.czu.cz

Abstract:

The unique photovoltaic power plant installed in Prague on the roof of the new buildings of National Theatre in Prague has been investigated. As the new buildings are very close to the old historical building of National Theatre designed in late 19th century, the PV power plant has to be totally invisible from the streets of Prague to not disturb historical panorama of the city. Flexible a-Si photovoltaic foils in the nearly horizontal position have been used because the placing is in the urban conservation area in the historical city centre. The operation started in the autumn 2009. The photovoltaic power plant is described in this paper and results of its operation are presented. The energy production data indicate that the degradation of the nearly horizontally installed a-Si panels is below 5% within 5 years period.

Key words:

Research of liquid contaminants influence on adhesive bond strength applied in agricultural machine construction

M. Müller

Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Science, Kamýcká ¹²⁹, ¹⁶⁵²¹ Prague, Czech Republic; e-mail: muller@tf.czu.cz

Abstract:

An adhesive bonding technology is a prospective bonding technology of diverse materials. Namely the research in the sphere of the degradation aspects affecting the adhesive bond during the technical life of the adhesive bonded complex is essential. Mineral and industrial fertilisers can be included as significant degradation agents. The aim of the research was to find out the relevant knowledge in the sphere of the degradation of the adhesive bonds placed in the water bath, the oil bath and the solution of the mineral and industrial fertilisers. The experiment’s results bring knowledge for producers of agricultural machines introducing adhesive bonding technology into their production programme. Two-component constructional epoxy adhesives were tested which were placed into the water bath, the oil bath and the solution of mineral and industrial fertilisers. Some agents caused such changes in the adhesive that the adhesive bond strength decreased to zero value already after ⁹0 days. Significant changes of the adhesive bond strength occurred in the interval ¹⁵–⁴⁵ days depending on the adhesive and agents. The strength decrease was connected with the change of a failure area from cohesive one to combined and then to adhesive one. The research showed that it came to diffuse seepage and to a partial corrosion of the adhesive bonded steel samples.

Key words:

bonding technology, degradation, fertilisers, fracture surface, oil, water