A number of renewable energy sources are available globally which promise to fulfil most of our future energy demands. One of the major barriers to the use of renewable energy, however, is the intermittent nature of its availability and the requirement of an efficient storage system to ensure robustness of the energy supply to the user. Alternatively the renewable energy source needs a grid back-up.

A modelling / analysis package for an energy system to meet the heat and power demands of small remote area dwellings is being developed at CSIRO. The energy system consists of a renewable energy source (solar PV, wind), electrolyser, hydrogen storage and a fuel cell. A back-up Diesel generator can also be included if deemed essential. The renewable energy system meets basic load demand when effective with excess stored in the form of hydrogen generated by the electrolysis unit. The electrolysis unit in conjunction with the fuel cell unit provide load levelling and meet load demand when the renewable energy source is fully or partially ineffective. Hydrogen generated by the electrolyser is stored at pressures up to 20bar. The system is controlled by the load demand and stored hydrogen gas pressure. The thermal energy from the fuel cell and the waste heat from the diesel generator are used to supply the hot water demand.

Based on electricity and hot water demand of a particular site on daily, weekly and yearly basis, the analysis package assists with component and cost optimisation and predicts environmental benefits.