DAKTris - Dynamic operating behaviour of absorption chillers in cross-building trigeneration systems
Project leader University of Innsbruck: Daniel Neyer
Project staff: Jacqueline Neyer, Alexander Thür, Norbert Hauer
Project partner
Funding organisation: BMVIT, Building of Tomorrow Plus, 4th call (project no. 840650)
Duration: 01.07.2013 - 30.06.2016
Combined heat, power and cooling (CHP) is one way of providing heat, cooling and electricity in buildings and across buildings. Initial results from relevant projects (e.g. PolySMART) with systems in the low output range show the potential, but also the steps required to implement the systems in an economical and primary energy-efficient manner. In particular, great importance is attached to harmonising the main components of the combined heat and power unit (CHP) and absorption chiller (AKM) and the system configuration (consumption profile, hydraulics, control, etc.).
Until now, standard absorption chillers (AKM), which are designed for other operating modes, have been used for CHP plants. By adapting the AKM to the higher drive temperatures and dynamic operating conditions of a CHP cogeneration system and realising potential improvements in the internal cycle, the aim is to create the conditions for successful and simplified (e.g. dry cooling tower instead of wet cooling tower) system technology implementation. By increasing the waste heat utilisation of the heat-driven CHP unit through the thermally driven cooling generation, the running time and thus the annual electricity generation can be significantly increased and thus made more economical.
With the help of market-relevant, economic and primary energy considerations, as well as dynamic system simulations, suitable profiles for cross-building operation (residential and non-residential buildings with different suitable utilisation profiles) are to be created and correspondingly adapted system configurations (with/without storage, selection of the suitable CHP type,...) with suitable control concepts are to be designed.
After adapting the AKM to these operating conditions, the different system configurations are analysed in hardware-in-the-loop measurements. The system performance and operating behaviour under dynamic conditions are realistically mapped and measured in combination with parallel system simulations. This method makes it possible to analyse and optimise the entire system in the laboratory. This reduces time and costs and increases the chances of successful implementation of the systems or installations. The data from the laboratory measurements can be used to make statements regarding the cost-effectiveness and primary energy efficiency of the system configurations or to optimise these systems.
Ultimately, only the optimal selection and coordination of the individual components at the overall system level can ensure economical and primary energy-efficient operation and thus make a significant contribution to the reduction (or even avoidance in the case of biogenic fuel-driven CHP units) of greenhouse gas emissions in the building sector.