Hydrogen addresses various issues in the world; like petroleum dependence, balance of payments, local air quality and finally global climate change. Hydrogen is ~75% of the known universe and doesn’t occur freely in nature. It’s a simplest element in the universe – one proton and one electro and It can be modified by fossil fuel or by natural gas. On earth, it’s not an energy source like oil or coal but only an energy carrier like electricity or gasoline – a form of energy, derived from a source that can be moved around.
Hydrogen is the most versatile energy carrier which can be made from any source and used for any service. It must be liberated from the main source by “Reform” HCs / CHs with heat and catalysts or by “Electrolyze” water (split H₂O with electricity). As per estimate, 1 kg of H₂ contains same energy as 1 U.S. gallon of gasoline. Presently, the maximum use of hydrogen is in petroleum refining and petrochemical production and other uses. Hydrogen has a long history as energy.
If we look into the history, it was started in 1820; hydrogen was used in an engine like device to do mechanical work – better than a steam engine as no warm-up time was needed. In 1920; a large scale plants in Canada using hydro-electricity from Niagara Falls to make hydrogen. Company was Stuart Electrolyser that is still in the business today.
In 1919; hydrogen as a fuel for vehicles was used in Germany. Currently, about 95 per cent of hydrogen is produced by steam reforming. Though, we could see more hydrogen generation from the other sources with more focus on research and development in future. As per Clean Cities learning program in US; hydrogen fuel cell industry is estimated around $2.5 trillion by 2021.
About Hydrogen Fuel Cell
Fuel cell is invented in 1838 by a Swiss scientist Christian Friedrich Schönbein. Fuel cells are similar to the batteries, but designed for continuous replenishment of energy via external fuel. The combination of oxygen from the air and water through electricity produce Hydrogen Fuel Cell. Hydrogen fuel cells are a type of electro-chemical cell which generates electricity by reduction and oxidation reactions within the cell. It uses three main components, a fuel (hydrogen), an oxidant (oxygen) and an electrolyte (proton exchange membrane) and emits only water as waste.
Image source: Greenerideal
Sufficiently electricity can be produced to power electric vehicle when hydrogen and oxygen from the air are fed into the proton exchange membrane fuel cell stack. Enough electricity can be produced to power electric vehicles. Hydrogen can be produced in two different ways, produce it on the ground and then store it on-board the vehicle (the direct hydrogen option) and produce the hydrogen on the vehicle by means of a tiny on-board hydrogen plant (the on-board fuel processor option).
Hydrogen fuel cells are more efficient than internal combustion; 50-60 per cent compared to 15-25 per cent respectively. The most commonly used hydrogen fuel cell is Polymer Electrolyte Membrane (PEM) in comparison to other types like; direct Methanol, Alkaline, Phosphoric acid, molten carbonate, solid oxide and Regenerative fuel cells.
For implementation of hydrogen as a fuel cell, one should know that hydrogen distribution via high-pressure cylinders and tube trailers has a range of 100-200 miles from the production facility. For longer distances of up to 1000 miles, hydrogen is usually transported as a liquid in super-insulated, cryogenic, over-the-road tankers, rail cars or barges, and then vaporized for use at the customer place.
The main advantage of hydrogen is that it burns nearly pollution-free and we can consider as a final clean fuel as there is no carbon in the fuel. The process of hydrogen is that when it is burned, it transforms into heat and water vapor which is suitable for drinkable water. The use of hydrogen fuel cell is increasing in the world due to favorable policy decisions made by world leaders.
The European Union, for example, is engaged in fuel cell buses in several cities and foresees that 20 per cent of transport fuel will come from hydrogen while Japan has plans to commercialize five million fuel cell vehicles by 2020.