HYDROGEN — FUEL OF FUTURE
Climate
Hydrogen is a chemical element. It exists naturally as a molecule, consisting of two hydrogen atoms bonded to each other. Besides being the simplest element, it is also the most common molecule of all. Discovered in 1766 by Henry Cavendish, hydrogen has since played a significant role in contemporary visions of the future, especially pertaining to the energy industry and locomotion. As early as 1874, in his novel “L’Île mystérieuse” ( The Mysterious Land ), Jules Verne, a French science fiction writer, had envisaged hydrogen and oxygen as the future sources of energy, replacing coal, the then supreme source of energy in the energy supply industry. He envisioned that hydrogen would be obtained from water through electrolysis.
“ Water will be the coal of the future.” ~ Jules Verne[1]
But what convinced him to say so? Take a look at hydrogen’s properties to find out.
First and foremost, hydrogen is superabundant in supply. It makes up 70% of the whole universe, making it the most-widespread component. This essentially means that no other energy resource is as infinite as hydrogen and that it is least unlikely to ever get exhausted. Besides, hydrogen is also a rich source of energy. It has the highest energy content than any common fuel, such as diesel or gas, by weight. This categorically means that an automobile that utilizes hydrogen energy will travel much further than the one which runs on an equal amount of gasoline. Furthermore, the availability of hydrogen also administers it an advantage. There are multiple resources to produce it locally, and it can be obtained from methane, gasoline, biomass, coal or water. This can either be done onsite, where it is to be used, or centrally and then distributed. Above all, hydrogen is practically a clean source of energy and non-toxic. When it is combined with oxygen in a fuel cell to generate electricity, which can then be used to drive an electric motor, the only by-products formed are water and heat. These do not have any known side-effects. In fact, after hydrogen is made use of, it is normally converted to drinking water for astronauts on ships or space stations. Last but not the least, unlike other energy resources, especially coal, it also does not produce carbon dioxide or other greenhouse gases that may then ultimately contribute to climate change.
By now, you might be wondering, “Well, if hydrogen occurs in such an ample supply, how do we obtain it?” So, let’s look at a number of ways to obtain it.
One of the ways and the most commonplace of all includes thermal processes. These processes typically involve steam reforming, reacting steam with hydrocarbon fuels, such as natural gas, diesel, renewable liquid fuels, gasified coal or gasified biomass, to produce hydrogen. Another way is electrolysis. This can take place in an electrolyzer whose function resembles much to a fuel cell in reverse: instead of using energy from the hydrogen molecule, which a fuel cell does, an electrolyzer creates hydrogen from water molecules. Solar-driven processes, encompassing photobiological, photoelectrochemical and solar thermochemical processes, are also used to produce hydrogen. These processes use light as the agent for hydrogen production.
On the contrary, hydrogen is not all-good. Rather, it possesses its own share of demerits as well. Let’s discuss them.
Firstly, hydrogen is expensive. Despite the fact that it is found plentiful in supply, the two main processes of obtaining hydrogen — steam reforming and electrolysis — actually elevate its production cost significantly. This is the most important reason why it is not used heavily across the world. Secondly, hydrogen production is dependent upon fossil fuels. Although it is a clean source of energy, hydrogen’s separation from its compounds requires substantial amounts of energy that is derived from non-renewable resources, for eg. coal, oil, natural gas, etc. This, in turn, causes immense pollution. Thirdly, hydrogen storage complications may also be posed. It has a low density which essentially means that it has to be compressed into its liquid state and stored in the same way at low temperatures to guarantee its effectiveness and efficiency as an energy source. Lastly and most importantly, hydrogen is dangerous. It is a highly flammable and volatile substance and lacks smell, which makes any leak detection impossible.
The Space Shuttle Challenger Disaster was a fatal incident in the United States space program that occurred on January 28, 1986, when the Space Shuttle Challenger broke apart 73 seconds into its flight due to the explosion of liquid hydrogen fuel tanks. It killed all seven crew members aboard, which consisted of five NASA astronauts, and two payload specialists[2].
Hence, in light of the above argument, it can be safely concluded that even though hydrogen fuel is a good alternative to non-renewable resources, it still requires some innovations and developments to minimize its drawbacks in order to make it the fuel of the future. Hopefully, that time is not too far away.
[1] “Hydrogen Fuel,” accessed November 22, 2020, https://www.shell.com/energy-and-innovation/new-energies/hydrogen.html.
[2] “Space Shuttle Challenger Disaster,” in Wikipedia, November 21, 2020, https://en.wikipedia.org/w/index.php?title=Space_Shuttle_Challenger_disaster&oldid=989876626.
Credits:
- Fig.1 provided by Wikimedia Commons, https://creativecommons.org/licenses/by-sa/4.0/legalcode