Hydrogen Economics: Boom or Bust?
In the ongoing search for sustainable, reliable, inexpensive and environmentally friendly energy sources, hydrogen has long been a contender. It is the simplest and most abundant element in the universe. This abundance, and the fact that when burnt as fuel its only remnants are water and warm air, make it a very attractive option. However, the costs and complications surrounding the creation and storage of liquid hydrogen are still holding it back from becoming a dominant fuel source. Experimentation to find cheaper ways of tackling this problem is taking place all over the world.
Currently, there are a number of ways to produce liquid hydrogen but the processes are all energy-hungry, to the point where the amount of energy required to produce the hydrogen is similar to the amount of potential energy stored in it. Clearly, this is not economically viable in most applications. Problems arise because hydrogen does not typically exist in nature by itself and it is often the process of separating it from other materials, such as water, that takes up the most energy. The most common processes being used are:
- Thermochemical Processes – Using heat and chemical reactions to release hydrogen from sources like water. Energy for this comes from fuel materials like natural gas, coal or bio-diesel.
- Electrolysis – As this process can be used to produce hydrogen with no greenhouse gas emissions and using renewable energy sources, a great deal of experimentation is ongoing to discover how to use it in a cost effective way.
Many other methods are used and more are being developed all the time.
Production costs are not the only issue preventing hydrogen being used as a financially viable fuel source. Making it into a usable form and storing it are also key factors due to the very low boiling point of hydrogen. Liquid Hydrogen has to be stored at around -253°C and be highly pressurised. Cooling and compressing it into this state is also an expensive and high energy consuming process.
However, NASA uses approximately 10 million pounds of liquid hydrogen a year. They favour hydrogen as the main fuel for space vehicles because it is very light and powerful as a rocket propellant. This is because it has the lowest molecular weight of any known substance and burns at around 3,000°C.
New methods of producing liquid hydrogen are being discovered all the time. These include: Direct Solar Water Splitting Processes which involve using light energy to split water into hydrogen and oxygen, as well as Biological Processes which use microbes to produce hydrogen through biological reactions. New production techniques, along with refinements to widely used processes, mean that cost effective hydrogen fuel production is coming closer and closer along with all the environmental benefits.
AML design and create equipment which can be used at cryogenic temperatures to aid in the type of experimentation which has the potential to make this use of hydrogen possible. For more information on their products, call 01903 884141 or email firstname.lastname@example.org to find out what they can do for you and your research.