PHOEBUS - An autonomous supply system with renewable energy: Six years of operational experience and advanced concepts

The PHOEBUS demonstration plant has been supplying the Central Library of F orschungszentrum Julich (FZJ) with solar-generated electric energy all year round and independent of the public grid since 1993. The central task was to rest the required storage using hydrogen as the energy carrier in conjun ction with an electrolyser and a fuel cell under realistic irradiance and c onsumption conditions and to demonstrate the feasibility of such a zero-emi ssion supply system. The general objective was to determine weak points fro m the operating experience and measured data obtained, to model the system in a component-oriented manner for simulation, to energetically optimize th e plant, to achieve high operational reliability and, above all, to propose and implement cost-reducing and advanced system modifications. With the ai d of validated simulation programs, it was possible to carry out optimizati on analyses for plant operation (annual scenarios) and plant configuration. Two advanced concepts were developed: PHOEBUS-2, a simplified system with reduced energy losses, and PHOEBUS-3, a wind-PV hybrid system supplying bot h electricity and heat. The advanced concepts PHOEBUS-2 and PHOEBUS-3 are t he theoretical basis for applications such as a solar home system, a solar village, a scientific polar station or a storage module for grid-connected operation that can be realized in the near future. (C) 2000 Elsevier Scienc e Ltd. All rights reserved.