Automotive solar hydrogen fuelling stations: Concept design, performance testing and evaluation

Hydrogen is expected to play an important role as an energy carrier in the transport sector in future sustainable energy strategies to meet the twin challenges of avoiding catastrophic climate change and depletion of low-cost petroleum resources. Provided the hydrogen is generated using renewable energy sources, its use in fuel cell vehicles can help to reduce greenhouse gas emissions, and contribute positively to achieving global energy sustainability and security, Automotive companies have now developed a range of commercial zero-emission hydrogen fuel cell vehicles. However, it is also essential to have a network of hydrogen fuelling stations to support the operation of hydrogen-powered vehicles, with these stations obtaining their hydrogen from zero-emission energy sources such as as solar and wind power.

The aim of this thesis is thus to study theoretically and experimentally the optimal designs for zero-emission hydrogen fuelling stations for generating, storing and supplying fuel to hydrogen fuel cell vehicles. The current status of hydrogen fuelling stations around the world is first reviewed, covering numbers by type of station, geographic location, scale, type of electrolyser, form of hydrogen storage and current plans for extending hydrogen fuelling infrastructure. It was found that there were more than 224 hydrogen stations in 28 countries in 2013, managed and designed by universities, research centres, industry shareholders, governments or non-governmental organisations. Experimental data on the operation of a small-scale experimental solar-hydrogen fuelling station at RMIT’s Bundoora East campus are reported. The experimental data on the performance of the PV array, PEM electyrolyser, batteries and inverter were then compared with a simulation of this system using the HOMER micro grid power simulation software, to test the validity of the simulation.

The validated HOMER model of a solar-hydrogen fuelling station was then applied to designing a medium-scale station to serve a fleet of ten fuel cell electric vehicles operating in Melbourne and a Middle East location. The options of a stand-alone solar-hydrogen station and one with grid back-up are both investigated. The optimal component sizes for PV array, electrolyser, and hydrogen storage tanks are found for all the options, and the associated levelised costs of hydrogen estimated. These levelised costs are then compared to the equivalent price of gasoline, taking into account the relative energy contents and energy efficiencies of hydrogen fuel cell vehicles and conventional internal combustion engine vehicles. Measures to enhance the economic competitiveness of the hydrogen-fuelled vehicle system, with the focus on solar-hydrogen fuelling stations in the future, are discussed, and corresponding recommendations made.