Introduction of >5KWe Cogenerating Biomass Pellet Boiler Prototype System

A revolutionary >5kWe cogen pellet boiler prototype system, designed and manufactured by ÖkoFEN, with Qnergy's Stirling engine inside, was introduced to the market. The biomass boiler is still under development and the first beta installations are expected before the end of the year to serve large residential and small to medium application requirements.

February 27, 2015

The cogen pellet boiler created much interest at the The World Sustainable Energy Days in Wels, Austria, a stage to most of the major wood pellet boiler manufacturers. ÖkoFEN's and Qnergy's latest technology is not only economical and automated but it also delivers heat and power embodied in one platform.

"5 kw of electricity and higher allows us to tap into new markets for cogeneration that so far have been out of our scope" said ÖkoFEN founder and CEO Herbert Ortner. "We are hoping to commercialize the product as fast as possible; the first pilot customers are expecting to take deliveries in the near future".

"With product life exceeding 60,000 running hours while being fuel agnostic and maintenance free, our product offers advantages no other product does" said Erez Harel, Qnergy's CEO. "ÖkoFEN was very quick to identify these unique advantages and has been a great partner in the project development".

How It Works

As the wood pellets are burned, heat from the burner flue gas is transferred to the head of the QB7500 external combustion Stirling engine, initiating a cyclic heating and cooling process of inert gas inside the engine. During this thermodynamic process, electricity is generated via the QB7500's linear alternator.

The heat then travels through the boiler to supply hot water for space heating, domestic use or for industrial and commercial process needs. This cutting edge cogeneration system generates inexpensive grid-quality electricity as a by-product of low-cost, environmentally friendly hot water production.

About ÖkoFEN
ÖkoFEN is the European specialist in pellet heating. Ecological research and development of small-scale ecological biomass heating systems was their primary objective and this mission is reflected in their company name ÖkoFEN. Ecology is the middle point of all their activities and is their philosophy throughout the whole company. When wood pellets were launched on the Austrian market in 1996, ÖkoFEN was the first Austrian manufacturer to offer an officially-certified pellet heating system to the public, in 1997. This pioneering activity has had wide-ranging effects throughout the industry and represents the beginning of a period of extraordinary market development. For more information, please visit

About Qnergy
Qnergy is an energy technology company developing and manufacturing high-efficiency Stirling-based power generation systems for residential, commercial, and industrial installations. A spin-off of Ricor Cryogenic and Vacuum Systems, Qnergy's Stirling technology has been successfully deployed in power systems for more than 40 years. With facilities in Israel and the United States, Qnergy offers a broad array of energy solutions including micro-combined heat and power (mCHP), solar power generation and solar CHP, remote power generation and more. For more information about Qnergy's Stirling platform and products, please visit

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