Economic and environmental analysis of a green energy hub with energy storage under fixed and variable pricing structures

With the increased use of intermittent renewable power generation, including wind and solar power, the need for energy storage is increasing. Repurposed hybrid electric vehicle lithium ion batteries have been shown to have energy storage potential at a modest capital cost. In this paper, the authors use a two stage MatLAB simulation to create and optimise, a net zero grid-connected facility. The yearly electricity price is calculated under various scenarios using two different pricing structures, fixed feed-in tariff and market pricing. The facility under consideration is a commercial distribution centre with refrigeration, onsite generation of hydrogen for fuel cell powered forklifts, solar and wind power generation, and re-purposed batteries for energy storage. Importantly, the feed-in tariff mechanism is shown to be a deterrent to implementing energy storage onsite, as well as to increasing the use of locally generated power. Although further savings are possible in the model, when energy storage is used, close to $50,000 in savings can be seen from electrolyser load shifting that requires no capital investment. The mechanism also negatively influences indirect electricity emissions, which is not consistent with environmental objectives.