Simulation and exergetic analysis of renewable multi-generation units for a building group

The building sector is responsible for more than one third of end energy consumption .The larger part of energy used for heating is won from highly exergetic fuels (e.g. coal, gas and electricity). Since living spaces are usually heated up to around 20 °C, low exergetic fuels are sufficient. Economically viable energy sources with low exergy share already exist for this application. Main target of the work carried out is to demonstrate advantages of exergy assessment for increased efficiency of community supply. For this reason different supply scenarios, based on fossil and renewable energy sources, are investigated. The different renewable energy supply units are regarded individually or in two or three-way combinations. In this study on one hand renewable and fossil-based supply are compared and on the other hand benefits by merging of several renewable energy suppliers for a small building group with a high energy standard are identified. For evaluation and identification of the best supply solution, the exergetic assessment method is applied. Additionally simplified aspects of operational management are regarded to compare the different supply solutions. The evaluation of the scenarios clearly shows that the combination of innovative supply strategies and exergetic assessment leads to an "holistic understanding" of the energy conversion chain and offers prospects for optimized community supply. Additional economic considerations and an analysis of emissions should be included in the evaluation. This paper represents modeling, simulation and exergetic analysis of renewable multi-generation units to supply a building group