Hydrogen has the potential to play a significant role in a future with diminishing oil supplies and increasing concerns regarding carbon emissions and climate change. Hydrogen as an energy carrier (as opposed to an energy source) is a means to store renewable and emissions free energy until it is needed. This makes it attractive as a complement to wind power which is intermittent in nature.
Because hydrogen doesn’t naturally exist on earth as a gas, it has to be produced by separating hydrogen atoms from a variety of substances. The two most common methods of producing hydrogen are steam methane reforming (SMR) and water electrolysis. SMR involves exposing natural gas to high temperatures to break it down into hydrogen, carbon dioxide and carbon monoxide. Electrolysis involves using electricity to split water into its component parts of hydrogen and oxygen.
The environmental benefit for hydrogen is totally dependent on the method used to produce it. Currently in Canada, the vast majority of the hydrogen produced is by SMR but because the process typically uses fossil fuels and emits carbon dioxide, the resultant hydrogen comes with a carbon footprint. On the other hand, if the hydrogen is produced through electrolysis from a renewable energy source such as wind power, then the process and the hydrogen can be relatively emission-free.
Notwithstanding the potential for hydrogen as a clean energy alternative, it will have to be cost competitive with conventional fossil fuel technologies for it to achieve widespread market penetration. While cost competitiveness of hydrogen in most fossil fuel dependent applications is not yet attainable, there are some niche markets where the economics may be feasible now. One of these markets is the supply of renewable energy based power systems to northern and remote communities of Canada (and beyond) that are dependent on diesel generators for electricity. In many cases, producing electricity from diesel translates into high electricity rates and this is where wind-hydrogen power supply systems can offer a competitive alternative with the added benefits of being self-sustaining and emission free.