Hydrogen is the most abundant element in the entire universe. Combined with oxygen it forms water which underpins the creation and continuance of life on earth. The environmental importance of hydrogen as an essential element to all living things and its versatility as a potential source of clean green and sustainable energy should not be underestimated.
The methods by which hydrogen is produced fall under three main technological pathways. They include the following:
This method involves the use of an electrical current to dissociate liquid water into its elemental gases, oxygen and hydrogen. The process which splits water into its constituent parts is known as electrolysis of water. The most commercially mature technology used for the production of hydrogen is via alkaline electrolysers (AE). Other mature technologies include making use of a polymer electrolyte membrane (PEM). Using a low or zero emissions electricity source to electrolyse water is currently the most efficient and cost-effective method in producing clean green hydrogen sustainably.
This method involves hydrocarbons, usually coal or biomass, interacting with heat and specific chemicals to produce syngas. Syngas is mixture of hydrogen, carbon monoxide and carbon dioxide gases. The syngas is reacted with water via a process known as ‘water-gas shift reaction’ which increases the concentration of hydrogen and carbon dioxide gases. In order to facilitate a low emissions pathway carbon capture, storage facilities must accompany the hydrogen generation plant.
Amongst the many emerging technologies Photolytic and Microbial production of hydrogen are the most promising and gaining significant interest within the sector.
Photoelectrochemical or photocatalytic water splitting involves the use of semiconducting photo catalyst or biological processes interacting with light and water to dissociate water molecules into its base gases, oxygen and hydrogen.
Photobiological water splitting involves the use of micro-organisms interacting with light to split water into its base gases, oxygen and hydrogen. Whilst in this case microbes use sunlight to break down organic matter there are other microbes that do not require the presence of sunlight.
Microbial biomass conversion (fermentation) involves micro-organisms breaking down organic matter in the absence of light to produce hydrogen. This process has been termed ‘dark fermentation’
Microbial electrolysis involves protons being produced from microbial breaking down of organic matter combining with an electric current to produce hydrogen.
Application of Hydrogen1
The commercial use of hydrogen primarily has been as a key input into a range of industrial processes across a number of applications as detailed in the diagram below:
Where hydrogen is produced using a low or zero emission sources it will have the effect of heavily decarbonising the energy sector and various industrial sectors.
Increase in energy prices
Electricity prices are currently high and will continue to increase into the near future.
Financial effect on families
Ordinary families are struggling to pay their power bills and as a direct consequence are going without other essentials in order to pay rising electricity bills.
This has a long-term effect on human health and wellbeing.
Trust in leadership
Community trust in the leadership of government to solve the perceived energy crisis continues to be eroded.
No real climate change policy and no real sustainable energy policy.
Cost of Complacency
The long-term cost to individuals, the nation and to the world in not acting fast enough to secure sustainable, clean green energy is immense.
The later we act the more significant the redress and its effect will be on all of us.
Declining demand in fossil fuels
Requirement to meet greenhouse gas emission targets has resulted in an economic shift away from investing in fossil fuel consumption internationally.
Renewable energy generation is now economically viable.
Electricity generation via large solar farms.
The larger the farm the lower the unit cost of production, thus resulting in cheaper electricity prices.
Clean green hydrogen production reuses existing resources in a cost effective and sustainable manner.
Ideal for domestic and foreign consumption.
Export markets to be targeted include but will not be limited to the Asia Pacific region.
- Energy sector
- Transport sector
- Glass manufacturing
- Metals processing
- Other as driven by demand
- Bruce S, Temminghoff M, Hayward J, Schmidt E, Munnings C, Palfreyman D, Hartley P (2018) National Hydrogen Roadmap. CSIRO, Australia.