The Slovene consulting and design company Protim Ržišnik Perc was awarded the prize of the Finance magazine for the best energy saving building of the year 2012 at the Energy Managers’ Days in Portorož, Slovenia. The building concerned is Kobra in Šentjernej – an administrative building with electronics retail store and a branch office of Volksbank. The object utilizes both geothermal and solar energy: a 50 kW PV plant together with the PV panels integrated in the car shelter produce electricity, solar thermal collectors heat the domestic hot water, and a reversible heat pump supplies the whole building by heat and cooling energy. Ground energy collectors preheat and precool the ventilation air. The rounded building corners show less thermal losses than the classical rectangular ones. The whole building is designed with focus on functionality so that the interior offers nice environment for creative and relaxing work, however, the main aim of the architects was to use energy efficiently, with high share of renewables.
The system was fine-tuned in 2012. It was found that most of the electrical energy (72 %) is spent on lighting and other electronic devices like IT, which is what will deserve most attention in the next years. Heating and cooling takes another 20 %, and air-conditioning 8 % of the total consumption. Total energy consumed in 2012 was 66 MWh (which gives 52,4 kWh/m2a), the PV plant produced 63,6 MWh. The whole building is considered passive in the total balances. If the consumption of electronic devices would be reduced by just 5 % the whole object would be energetically active: it would produce more energy than it consumes.
The building control system supplier, Kovintrade d.o.o., distributor of Domat Control System in Slovenia, supplied installation and programming of the control system which is based on the Domat MiniPLC process stations. Great emphasis was put on lights and blinds controls. These systems are integrated so as to minimize energy consumption in offices and public areas. To monitor values and control the system, RcWare Vision SCADA was used. The CEO and owner of Kobra, Branko Kovačič, believes that the control system played a significant role in the decision of the jury: the energy savings are achieved thanks to sophisticated integration of all subsystems, energy metering, and colour energy efficiency bar indicators.
The architects from Protim Ržišnik Perc chose Domat also because their experiences from their own building in Šenčur. Kobra is another building where modern technology means not only comfort and design, but also proven results in energy savings.
Image: Protim Ržišnik Perc d.o.o.