Hydrogen is the most abundant element in the universe.
As an energy carrier, hydrogen has two outstanding properties. Firstly, it has a very high energy density, with each kilogram of hydrogen containing about 2.4 times as much energy as natural gas. Secondly, its energy can be released either as heat through combustion or as electricity using fuel cells.
Most importantly, for either case, the only other input needed to release this energy is oxygen and the only emission is water. This lack of greenhouse gas emissions means that it is a clean fuel with the potential to decarbonise many energy and industrial sectors.
Hydrogen is a highly versatile energy carrier and feedstock, and has the potential to be used across a wide range of applications including:
- in many forms of transport, where opportunities are derived from hydrogen fuel cell vehicles and associated refuelling stations;
- in buildings (both residential and commercial), where there are opportunities for hydrogen to be blended into existing natural gas networks;
- in power generation, where opportunities are derived from hydrogen as a leading option for the storage of renewable energy (potentially for weeks or even months);
- in industrial processes, where the current production of hydrogen from (unabated) fossil fuel sources offers opportunities for its replacement by clean hydrogen and a significant reduction in emissions.
The obstacle to realising hydrogen’s clean energy potential is that, on Earth, hydrogen is virtually non-existent in its free form. This means that energy is needed to liberate it from other materials such as water, biomass, fossil fuels or minerals.
Recent technological developments, both in the production and use of hydrogen, have meant that a global effort is underway to develop hydrogen markets and achieve its widespread use as a clean energy carrier. In Australia, momentum is increasing as supportive policies have been announced and projects of varying types and scales are exploring opportunities for clean hydrogen in both domestic and export markets.