The first Ökofen Pellematic Condens_e CHP-unit in Finland has been installed to Sirkkala Energy Park at Karelia University of Applied Sciences. The nano scale CHP (combined heat and power) unit produces energy with a condensing pellet boiler and an integrated Stirling engine. The whole unit requires only 1.5m² of floor space. The CHP unit is installed as part of Sirkkala Energy Park’s hybrid energy system that produces heat and electricity for Energy Park and for two elementary schools. This CHP unit is already connected to Fronius Symo Hybrid inverter, which will be connected to a small array of Panasonic HIT pV -panels. When battery storage is added to this system it will be a true standalone system.
Ökofen Pellematic Condens_e CHP-unit is designed for 6mm pellets, but it will run with 8mm pellets. The unit has a nominal thermal output of 9kW and 600W of electricity, but it can modulate the production between 3-13kW thermal and up to 1kW electricity. Unit size is ideal for single houses and requires only a little maintenance, just some brushing and vacuuming for pellet boiler and heat exchangers. The Stirling engine is nearly maintenance free.
With the Pellematic Condens_e it is possible to generate electricity and heat for your own consumption. Economically, at least in Finland, the electricity generated should primarily be used at home and only the excess available electrical energy should be fed back into the public electricity grid.
The Integrated Microgen Stirling engine produces AC power at 50Hz from the thermal energy the pellet boiler produces. The electricity production is based on a thermal gradient, so the efficiency is dependent on the temperature difference of returning water flow from the hydraulic heating circuit. The cost of the unit is approximately €23,000, excluding the possible requirement for hydraulic components or larger-scale fuel storage.