Techno-economic study of a PV-hydrogen-battery hybrid system for off-grid power supply: Impact of performances' ageing on optimal system sizing and competitiveness

Abstract

The use of intermittent renewable energy sources for power supply to off-grid electricity consumers requires either additional power sources or energy storage solutions, in order to manage the time mismatch between energy production and load requirements.We investigate in this paper the interest of a hybrid solar energy system, including a lithium-based batteries bank and a hydrogen chain (electrolyser, gas storages and fuel cell), for an off-grid application. This system is compared with two reference cases: PV-diesel generator and PV-Batteries. These different systems have been represented using empirical and semi-empirical models and are simulated with the CEA made ODYSSEY platform.The originality of our study lies in the simultaneous optimisation of the power management strategy and the components’ size, and in the detailed modelling of the components (power consumption of the auxiliaries and ageing approach in the form of performances degradation).The PV-Batteries-H2 system is operated by an efficient power management strategy and its optimal sizing is assessed on the basis of technical (e.g. load satisfaction) and economic (e.g. levelized cost of electricity) criteria. The results highlight the important role of the hydrogen chain in reducing the cost of the supplied energy. It is also shown that performances degradation of the hydrogen chain has a limited impact on the system optimal sizing and economic results.