Project: Biomass micro cogeneration power plant for collective building

To meet the objective of the European Union of a 20% reduction of greenhouse gas emissions by 2020, biomass micro-Combined Heat and Power (mCHP) technology based on external combustion engines is seen as one of the most appropriate answers. To this day, 65% of raw material necessary to produce electricity is lost in the form of heat. Such mCHP technology could greatly contribute to increase the efficiency of energy production by converting heat into electricity._x000D__x000D_The Woodtricity project will develop a micro-cogenerator working with an automatic wood pellet boiler and a Rankine engine devoted to collective building use, whose surfaces shall be between 500 and 1 500 m² for heating use, and up to 10 000 m² for domestic hot water use only. This Rankine engine will be used through a system patented by French mCHP technology developer EXOES, SHAPE™ (Sustainable Heat and Power Engine), enabling the conversion of calories from a heat source into electricity and heat. The automatic wood pellet boiler will be provided by ÖkoFEN, Europe specialist for pellet heating systems._x000D__x000D_EXOES and ÖkoFEN aim at achieving an overall energy efficiency approaching 90%, when cumulating electrical and thermal production. This will imply to reach the following technical performances:_x000D_- 3 electrical kW as outputs from the Rankine engine_x000D_- 18 thermal kW from the SHAPE™ and 31 thermal kW from the boiler dedicated to the heat supply of building_x000D__x000D_To do so, the Woodtricity project will capitalize on previous researches operated by EXOES and ÖkoFEN. In fact, an old SHAPE™ prototype has already been coupled to a boiler PE56, without being reliable enough yet. Equally, a primary heat exchanger has been developed in cooperation with French Atomic Energy Commission (CEA), as well as a small part of the regulation. However, these developments were either not reliable enough or too expensive. Thus, a proof of concept has been done, without having a product technically ready for market._x000D_Based on this expertise, one of the CO innovations of the Woodtricity project will lay in the development of a heat exchanger. There, EXOES and ÖkoFEN will have to comply with an objective of retrofitting, that is, integrate the heat exchanger into the ÖkoFEN boiler without fundamental modification. This will imply many technological breakthroughs. Firstly, EXOES will develop a small and non-lubricated complete Rankine cycle, functioning in closed loops and with overheated steam with a COtenance interval of the system of about 500 hours. In addition, the heat exchanger will need to be compatible with the corrosive combustion of wood pellet, thanks to the use of new materials and changes in the combustion room. Besides, Woodtricity will develop overheated steam regulation with reciprocating engine piston and intake & exhausts organs._x000D__x000D_Yet, the miniaturization of the Rankine cycle with overheated non-lubricated steam will imply different risks to be tackled for. Firstly, the Ps may have to deal with a lack of resistance of the non-lubricated piston rings. This could be due to combined constraints of stress, temperature and thermal cycling. Moreover, EXOES and ÖkoFEN may encounter difficulties in the production of the heat exchanger, as well as in the regulation of overheated steam and in the integration of the micro-power plant to the boiler. These technological risks shall be respectively overcome by appropriate solutions that will be presented hereafter._x000D__x000D_At last, within a year after the end of the project, the final cogeneration system shall enter the market of automatic wood pellet heating systems. By 2020, European sales of wood pellet boiler are expected to rise yearly by 15% (from 40 000 units in 2007 to 250 000 in 2020), with a market that should correspond to 5 billion euro per year. ÖkoFEN will target industrial buildings, schools and big residential buildings, where the boiler PE 56 is COly used as a base-load boiler. In the first years of commercialization, ÖkoFEN expects to sell between 200 to 300 micro-power plants per year. With 4 000 sales per year in 2020, EXOES aims at covering 1.5% market share of automatic pellet boilers. EXOES will sell its products to the 10 major European wood boilers’ manufacturers, including ÖkoFEN, achieving 60% of sales of automatic wood pellet boilers in Europe. These estimates are only valid provided that the system is market-ripe and that the general basic conditions (depreciation time, legislation, funding etc.) are met._x000D_In terms of countries, ÖkoFEN aims at marketing those where the difference between the price of pellets and the price of the electricity from the grid is at the highest: Denmark, Germany, Switzerland, Italy and the Netherlands. In fact, the system developed thanks to the Woodtricity project will allow prospective clients to reduce their bills of 30 to 50%. This will be enabled by a cost of the electricity produced by the system inferior to the price of regular national electricity.

Acronym Woodtricity (Reference Number: 7281)
Duration 03/09/2012 - 04/07/2014
Project Topic Development of a biomass micro cogeneration power plant specifically designed for collective building use. The system will be composed of a overheated steam Rankine engine and an automatic wood pellet boiler.
Network Eurostars
Call Eurostars Cut-Off 8

Project partner

Number Name Role Country
2 EXOES Coordinator France
2 ÖkoFEN Forschungs- und Entwicklungs GmbH Partner Austria