Implementation of a Fuel Cell System Model into Building Energy Simulation Software IDA-ICE

Due to constantly increasing electricity consumption, distribution networks are becoming overloaded and sometimes unstable. Decentralization of power generation using small-scale local cogeneration plants becomes an interesting option to improve economy and energetic reliability of buildings. It is expected that utilization of stationary fuel cell systems in buildings will become one of their most important fields of application. In northern countries, like Finland, effective exploitation of heat from fuel cells is feasible. Even though development of some fuel cell systems have already progressed to a field trial stage, quite little is yet known about building and fuel cell interaction during a dynamic operation. International cooperation under IEA/ECBCS/Annex 42 aims at filling this gap and the study presented in this report is part of this effort. A model of solid-oxide fuel cell system has been developed, in which the fuel cell power module is described with polynomial equations, based on specifications defined within Annex 42. The model has been integrated with the building energy simulation tool IDA-ICE (Indoor Climate and Energy) using Neutral Model Format (NMF) language. The most important result in this phase is the model itself. An extensive set of simulations have been carried out to validate the model performance and results are in perfect agreement with other programs developed within Annex 42. Currently, the work is in progress on refinement and further development of the model. In the next step a new function will be added to facilitate evaluation of the modelled plant (e.g. cost-efficiency, indoor climate quality).