  Nearly all types of energy systems (such as power systems, natural gas supply
systems, fuel supply systems, and so forth) are going through a major
transition from centralised, top-down structures to distributed, clean energy
approaches in order to address the concerns regarding climate change, air
quality, depletion of natural resources, and energy security, whilst also
enabling the supply of energy to communities in line with the goals of
sustainable development. Accordingly, the establishment of the concept of
sustainable, decentralised, multi-carrier energy systems, together with the
declining costs of renewable energy technologies, has proposed changes in the
energy industry towards the development of integrated energy systems.
Notwithstanding the potential benefits, the optimal capacity planning of these
systems with multiple energy carriers (such as electricity, heat, hydrogen, and
biogas) is exceedingly complex due to the concurrent goals and interrelated
constraints that must be satisfied, as well as the heavily context-dependent
nature of such schemes. This paper puts forward an innovative optimal capacity
planning method for a cutting-edge, stand-alone multiple energy carrier
micro-grid (MECM) serving the electricity, hot water, and transportation fuel
demands of remote communities. The proposed MECM system is equipped with wind
turbines, a hydrogen sub-system (including an electrolyser, a hydrogen
reservoir, and a fuel cell), a hybrid super-capacitor/battery energy storage
system, a hot water storage tank, a heat exchanger, an inline electric heater,
a hydrogen refuelling station, and some power converters. A numerical case
study for the optimal capacity planning of the suggested MECM configuration, to
be realised on Stewart Island, New Zealand, is presented to evaluate the
effectiveness of the proposed optimisation method.
