ExTra
Conventional heating networks are to be transformed into highly efficient heating and cooling networks by integrating a new type of "exergy transformer".
In its current climate and energy strategy, the Austrian federal government has set itself the goal of significantly reducing Austria’s greenhouse gas emissions by 2030. In order to achieve this goal, the energy demand of buildings must be significantly reduced and sustainably covered – highly efficient district heating and cooling is to replace conventional grids here. The project ExTra – ExergieTrafos for heating and air-conditioning by district heating focuses precisely on this challenge and sheds light on the potential of the promising coupling element power-cooling-coupling in relation to an urban energy network (cooling, heating, electricity).
Opportunity-rich solutions for a sustainable future
The heating network with today’s usual supply temperatures is to be upgraded by adding new types of exergy transformers to the heat-exchanging transfer stations. These are driven by the district heating and provide the following service in summer and winter: cooling for air-conditioning, simultaneous heating and cooling as well as heating when temperatures are lowered in order to minimise network losses.
Possible technologies for such exergy transformers are absorption technology and ejector technology, which are thermally driven, novel multi-stage cycle processes. Ejector technology is already known and established in itself and is said to offer a possible economic alternative to absorption technology by recovering the expansion energy. In the present project, the approach of the steam jet apparatus is to be converted into that of a hot water jet apparatus. With the expertise of the project team FH Burgenland, TB Beckmann and Wien Energie, system solutions for absorption and ejector technology will be developed and simulated for ExTra and their integration into heating and cooling networks will be evaluated economically and ecologically.
