The new Research & Development building - our facility, 100% eco-friendly!
Staying on top is much harder than just reaching the top once, and Pipistrel is well aware of this. Therefore, all available funds are transferred directly into Research and Development. For this very purpose a new research centre for applicative technologies, featuring an aerodynamics laboratory, laboratory for development of composite materials, laboratory for development of application of organic photovoltaic solar cells to uneven surfaces and the laboratory for aircraft testing has been built.
In the future, we can expect a rapid increase of energy prices and stricter limitations on energy consumption. Pipistrel d.o.o. Ajdovscina is already aware of this challenge.
That is why we built our new research institute with the goal of energetic efficiency and environment conservation in mind.
..and the reality!
The new building's footprint measures 2400 m2 and had been designed as environmentally friendly and emission-free. All energy consumed by the building and the activities inside do not put any stress on the environment and is also used very rationally and efficiently. This allows for the building to be completely energetically self-sufficient using renewable energy sources alone. The construction of the building was a huge challenge, especially since it represents a huge short-term expense while the results of nature protection are only visible long-term.
The buildings location, orientation, as well as the shape of the roof had to be adjusted so that the solar radiation could be taken advantage of as much as possible. A major difficulty is the local phenomenon called "Burja", a very strong and gusty wind, at times exceeding speeds of 200 km/h. Pipistrel's virtual wind tunnel produced an aerodynamic study about Burja's effect on the building and its shape. As a result of this analysis, the building is oriented at an azimuth of 170° and not exactly southwards. The roof is inclined at a 30% bank, providing optimal efficiency to the solar power plant.
All main glass surfaces face north (away from the sun), so that only the diffuse light can enter the building. All doors and windows have above-average insulation (K=1.0). To minimize thermal losses, polyurethane roof and side walls "sandwich" panels with thermal coefficient of K=0.18 are used.
All the windows that face south are designed with an precisely calculated extended roof or balcony above them, so that in the summer the direct sunlight and heat cannot enter. In the winter however, when the building could use additional energy, the lower angle of the sun allows the sunlight to enter the building.
Newest and greenest technology
The building incorporates geothermal heat exchangers in symbiosis with a large geothermal accumulation field. The heart of the building is one of Slovenia's largest solar power plants which (combined with a cogeneration module) covers for all energy needs of the building, electricity and thermal energy conditioning included. Air conditioning is established in an innovative and efficient manner using ground radiation heating and cooling. This allows for the minimum possible temperature difference between highest and lowest fluid temperature in the building and yields maximum efficiencies and spares costs. The central intelligent supervisory system controls the whole building, including the lighting with regard to the current insolation, energy recuperation and ventilation systems and all that with respect to current input economic parameters.
Geothermal heat exchangers placed around the building are the primary source of thermal energy. A total of 1,200 metres of vertical geothermal heat exchangers provide approximately 36 kW of thermal energy.
The Geothermal accumulation field is a ground collector which functions as a storage for exchange and deriving of thermal energy at rate of 25 W/m2. The capacity of the accumulation field measures 5000 m3 and is placed underneath the whole of the building in form of 4 collectors each 250 m2 in footprint.
Geothermal heat exchangers are connected to the Geothermal accumulation field so that it is also possible to run the system without using the heat pump on days when pumping the heat transfer medium around the building suffices.
As requirements for the higher or lower temperature of the medium arise, the heat pump is activated by the system automatically.
Spare heat is accumulated inside the Geothermal accumulation field.
Covering own need for electrical power while at the same time supplying the technical heat necessary for the building, a cogeneration unit of 43 kW heating power is installed. The cogeneration plant is powered by a natural gas motor to be later exchanged for a biomass-driven motor. It produces both electricity and heat. Mechanical energy is used to run the generator, which produces electric power. By cooling-down the motor and exhaust gases, which are ran through a catalyser and a built-in heat exchanger, also the spare energy is transferred and used for heating up water further used for technological processes. This water reaches a temperature of 80° C. The heat produced by the co-generator can be sent to the heating distributor (35° C point) in the new power station, as well as to the boiler station inside the existing production facility. The total energy efficiency of the cogeneration system reaches 85%, which yields considerable savings.
The heat pump is used to either chill or heat the heat transfer medium (glycol-based fluid). The heat pump is a compact type with three built-in parallel hermetic compressors. Hence there is only the need for a single cooling circuit with a flat freonic steam generator (condenser), cooling controllers and electric harness. Derived heat from the geothermal heat exchangers heats the 30% glycol transfer medium on the primary side of the pump the lower temperature (35/25° C) transfer medium on the secondary side. The medium is then pumped throughout the circuit.
Heating and cooling is established in an innovative and efficient manner using ground radiation. This allows for the minimum possible temperature difference between highest and lowest water temperature in the building and yields maximum efficiencies and savings. The ground radiation system consists of a mesh of pipes made of high-density polyethylene PE-Xc. The temperature system of heated water is 35/25° C, in the summer 13° C. The distance between pipes in the mesh was chosen carefully so that the ground is never heated to more than 29° C. Ground radiation covers for the complete thermal losses of the building.
Ventilation inside the building is carried out using recuperators, which are able to intercept 90% of thermal energy returning to the rooms. Gasses from the welding shop are also recycled with ionisators and return to the rooms at the same temperature (via recuperators).
Solar Power Plant
The heart of the building is a solar power plant which, combined with a cogeneration module covers for all energetic needs of the building, electricity and thermal energy conditioning included. The entire roof of the building is covered with photovoltaic panels, capable of producing 107 kW of energy and thus earning it a place among the largest solar power plants in private owneship in Slovenia.
Panels used are SolarWorld mono-crystal silicon panels with 25 year of guarantee until 80% off-peak efficiency value. The photovoltaic panels are coupled with 13 network inverters SMA Sunny Mini Central with 98% efficiency. Network inverters converts DC power from the panels to AC network distribution power and send it via a counter directly into the distribution network. Sunny WebBox monitoring hardware and software provides data around the solar powerplant for public view on the internet. The solar power plant has potential to grow to 200 kW power by adding photovoltaic panels to the existing Pipistrel building as well.
You can follow the daily production on the front page www.pipistrel.si, at the bottom.
System control and optimization
The central intelligent supervisory system controls the whole building (the geothermal heat exchangers, the air conditioning, heating and cooling of the building ), including the lighting with regard to the current insolation, energy recuperation and ventilation systems.
Alongside these tasks the central processor prioritizes the main system units (boiler, co-generator, heat pump, direct heat exchange, by-pass of the heat pump, etc.) according to the chosen economy-based input values. This is how the most efficient and cost effective operation of the complete building is ensured.
Quite apart from the numerous savings of the new building (enabled by the super-efficient insulation, low-temperature system of heating and air conditioning, ventilation air energy recuperation, intelligent light system, geothermal heat exchangers, geothermal accumulation field for energy storage, heat pump and co-generator, the and solar power plant alone is expected to reduce the carbon footprint for 65,000 kg of CO2 every year.
On top of that, the savings from replacing the oil based heaters amount to 37,295 kg of CO2.
Replacing the earth-gas heaters means additional saving of 49,990 kg of CO2, and savings from using energy cogeneration: 33,350 kg of CO2 per year.
A rough estimate for yearly savings of energy is 95.000 kWh.
The total CO2 savings from all the systems combined are 180,635 kg of CO2 per year!
Economic savings (pay-off period and other economic indicators) were intentionally not considered in the project, as the environmental benefits outweigh them by far. Being energetically independent in case of energy use limitations in the future was more important.
The value of the new complex and financing
The new Pipistrel's research & develompent center utilises all the best and most economic energy systems known at this moment. It is unique in this part of Europe and one of the most advanced structures in the world!
The value of the investment is 2,5 million Euro, out of this 370.000 EUR of non-refundable funding by the government and the European Union.
The company financed this investment with its own resources and with credits granted by the "EKO" fund and NKBM bank with subsidised interest rates by the Municipality of Ajdovščina.
Pipistrel continues its philosophy already demonstrated in form or World-class award-winning aircraft by investing into environmentally-friendly premises, researching new energy sources and innovative propulsion systems. The future will bring highly important strategic decisions, demanding the preservation of the environment - and the company is already well aware of this. Every single strategic document describing company's vision and future already mentions energy preservation as the first priority.
Regardless of the higher costs of construction and planning of such buildings, Pipistrel believes that it will soon become evident that such energetically self-sufficient constructions are indeed more cost effective over longer periods of time. Furthermore, we are convinced that other businesses will need to follow this vision shortly due to the sheer need for energy preservation as well as for the upcoming environment fees which governments will impose sooner or later.