Do you know the use of hydrogen? NO, it is not only limiting to flying balloons. Hydrogen energy is also a great source of renewable energy. In this article, you are going to learn about hydrogen energy.
What’s in it for me?
- Hydrogen Energy overview
- Brief history
- Common methods of producing hydrogen fuels
- Hydrogen Fuel Cells
- Various uses for hydrogen energy
- Advantages of hydrogen energy
- Disadvantages of hydrogen energy
- Conclusion
- FAQs
Hydrogen Energy overview
Hydrogen is a chemical element in the periodic table denote by symbol H. Atomic number (Proton number) of hydrogen is one as it is consists of one proton and 1 electron.
Hydrogen is the lightest element in the periodic table as well as the amplest chemical substance in the Universe with around 75% of the baryonic mass. (In short ¾ of everything is consists of hydrogen).
However, it is not available naturally as a gas on the earth it is always in combination with other elements like (H2O) water, (HO2) hydroxyl radical, (H2O2) hydrogen peroxide, etc.
Hydrogen is lighter than air and hence mostly not present in the atmosphere. it can easily escape earth’s gravity.
Many of our fuels, such as gasoline, natural gas, methanol, and propane have hydrogen compounds present in it as a hydrocarbon.
When we use pure hydrogen as fuel after burning the by-product it produces is clean water it is so pure that we can drink it without any processing on it.
Nasa using liquid hydrogen to propel space shuttle and rockets into orbit since 1950 after providing power to shuttles electrical systems the water waste crew use to drink.
Hydrogen also having great qualities likes non-toxic, non-metallic, odorless, tasteless, colorless, and highly combustible diatomic gas.
Brief history
In 1671 Robert Boyle first produced hydrogen gas while he was experimenting with iron and acids.
After that British scientist Henry Cavendish has first identified hydrogen energy as a distinct element after he developed hydrogen gas by subjecting zinc metal to hydrochloric acid in 1776.
He made another discovery during a demonstration to the Royal Society of London when he states that if a spark flows through the hydrogen gas it produces water in the process.
Because of this famous remarkable development led us to the conclusion that water (H2O) is a compound of hydrogen and oxygen.
Soon after this hydrogen energy technology has grown exponentially and today, we look at it as an alternative energy source to power vehicles, electric systems, electricity, and production of pure water.
Common methods of producing hydrogen fuels
- Thermal Process
- Electrolytic Process
- Solar-Driven Process
- Biological Process
Thermal Process
This process mainly involves steam reforming, this is basically a high-temperature process. During this process, high-temperature steam reacts with hydrocarbon fuels to produce hydrogen out of them.
These hydrocarbon fuels are natural gas, diesel, renewable liquid fuels, gasified coal, or gasified biomass. However out of all these options, natural gas is prefect to produce hydrogen
Natural gas contributes to 95% in hydrogen production.
Natural gas contains methane (CH4). Using this we can generate hydrogen. For that we use the following two methods.
- Steam-methane reformation
- Partial oxidation
Steam-methane reformation
Steam reforming is an endothermic process which means we need to supply heat to the process for the reaction to happen.
Firstly, methane will react with steam at a 700-1000 °C under 3-25 bar pressure (1 bar = 14.5psi) in the presence of a catalyst to produce hydrogen, carbon monoxide, and a relatively small amount of carbon dioxide.
Secondly, In a process called water-gas shift reaction, carbon monoxide will react with steam using a catalyst to produce carbon dioxide and more hydrogen.
Finally, in a process known as pressure-swing adsorption, impurities and carbon dioxide will separate, and only pure hydrogen will left.
Steam-methane reforming reaction
| CH4+H2O(+Heat) = CO+3H2 |
Water-gas shift reaction
| CO + H2O → CO2 + H2 (+ small amount of heat) |
Partial oxidation
Since hydrocarbons and methane present in natural gas react with each other in a limited amount of oxygen (partial oxidation) oxidize is difficult.
As the limited amount of oxygen present in the process,therefore it is difficult to completely oxidize the hydrocarbons to carbon dioxide and water.
Therefore, reaction products contain primarily hydrogen and carbon monoxide and a small amount of carbon dioxide.
Now in a water-gas shift reaction process carbon monoxide again reacts with water to form carbon dioxide and more hydrogen.
Partial oxidation is an exothermic process therefore it generates heat. This process required a smaller reactor vessel and it is faster than the steam-methane reformation process.
Partial oxidation of methane reaction
| CH4 + ½O2 → CO + 2H2 (+ heat) |
Water-gas shift reaction
| CO + H2O → CO2 + H2 (+ small amount of heat) |
Electrolytic Process
Electrolytic is a process in which electric current flows through a substance that creates a chemical change (the process of losing or gaining an electron) in that substance. Therefore using this great process we can separate hydrogen and oxygen from water.
On the other hand to perform this process we need apparatus consisting of positive and negative electrodes kept apart from each other and dipped into a solution that contains positively and negatively charged ions this apparatus is called an electrolytic cell.
Firstly, to produce hydrogen from the water power source is connected to the positive and negative electrodes dipped into the water.
As current will start flowing through the system hydrogen will appear at the anode which is the negatively charged electrode and after that oxygen will start appearing at the cathode which is the positively charged electrode.
Assuming ideal faradaic first law of efficiency (Faraday’s First Law of Electrolysis states that the chemical deposition due to the flow of current through an electrolyte is directly proportional to the quantity of electricity (coulombs) passed through it.).
However, the amount of hydrogen generated in the process will be twice the amount of oxygen and they both are proportional to the total electrical charge conducted by the water
Solar-Driven Process
In this process, for production of hydrogen light is very essential. There are three different solar-driven processes.
- Photobiological – In this process photo syntactic activity of bacteria and algae are used to produce hydrogen
- Photoelectrochemical – In this process specialized semiconductors are used to separate water into hydrogen and oxygen.
- Solar thermochemical – In this process concentrated solar power to drive water splitting reactions often along with other species such as metal oxides.
Biological Process
In biological process microbes such as bacteria and microalgae produce hydrogen through biological reactions.
The biological process has two types.
- Microbial biomass conversion – In this type of processes the microbes break down organic matter like biomass or wastewater to produce hydrogen
- Photobiological processes – In photo biological processes microbes use sunlight as the energy source.
Hydrogen Fuel Cells
The fuel cell is a device that uses a combination of hydrogen and oxygen to produce heat and electricity, But with water as a by-product of the process.
This is a great substitute for IC engines, coal-burning power plants, and nuclear power plants as they also produce heat and electricity but at a cost of harmful by-products and environmental health.
Since O2 is naturally present in the atmosphere we only need to supply hydrogen by various methods we saw earlier.
So many people compare fuel cells with electric batteries as both works on the same principle of converting the energy produced by a chemical reaction into usable electric power.
Fuel cells will only produce electricity as long as fuel (Hydrogen) is supplying to it.
Various uses for hydrogen energy
- Light-duty highway vehicles– 50-90 % emission reduction compared to gasoline vehicles
- Specialty vehicles – 35% emission reduction compared to diesel and battery-powered vehicles.
- Transit buses – Efficiency is 1.5 times better than the IC engine and 2 times better than natural gas IC engine busses.
- Auxiliary power units (APUs) – Makes a 60% reduction in emissions compared to truck engine idling.
- Combined heat and power (CHP) systems – Since a 35% to 50% reduction in emissions over conventional heat and power sources.
- Residential applications – Gives high potential.
- Industrial applications – Use in industries like oil refining, ammonia production, methanol production, and steel production.
- Commercial applications – Telecom towers for providing back-up power.
Advantages of hydrogen energy
- Firstly it is a renewable energy source.
- Secondly, it is an almost clean energy source.
- Thirdly hydrogen is non-toxic.
- It has great efficiency compared to other energy sources.
- Similarly, It can use in space shuttles and rockets.
- Also, the storage of hydrogen energy is possible.
- In addition hydrogen-powered vehicles have a great fuel economy.
- It is a consistent source of energy.
- The risk of chemical exposure is very less.
Disadvantages of hydrogen energy
- Firstly It is an expensive source of energy.
- Secondly, it is very difficult to store due to its lower density.
- Thirdly it largely depends upon fissile fuels to produce hydrogen.
- Presently hydrogen energy is not widely available.
- It is highly flammable.
- Transportation cost is more compared to others.
Conclusion
With great power comes great challenges. Hydrogen energy perfectly fits into this saying.
Hydrogen energy is the greatest among all other renewable energies around but hydrogen production using renewable energies (Green Hydrogen) like Solar energy, Wind energy, and Hydro energy is the biggest challenge in front of us along with its transportation and storage.
However, to increase the development of the hydrogen energy sector in India, National Hydrogen Energy Road Map (NHERM) was prepared and adopted by the National Hydrogen Energy Board in January 2006.
Objectives of NHERM are found out the ways to introduce hydrogen energy, commercialization of hydro energy, and creation of hydrogen energy infrastructure in the country.
Therefore it covers all the things that come under the development of hydrogen energy in India. Starting from its production, storage, transport, delivery, application, codes & standards, public awareness, and capacity building.
Indian Hydrogen energy market was value 50 million dollars in 2017 and expect to reach 81 million dollars by 2025 with CAGR of 6.7.
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FAQs
Currently, hydrogen is mainly used as a fuel in the NASA space program. Firstly hydrogen fuel cells power the electrical systems of the shuttle. Secondly, the hydrogen fuel cell is also used to produce pure water for the shuttle crew.
Overall, the global market for hydrogen energy storage was US$ 12.96 billion in 2018. However the projected size of the global market for hydrogen energy storage is estimated at US$ 21.15 billion in 2027.
The global Hydrogen Fuel Cells market is valued at 1686 million US$ in 2020 and it is expected to reach 4476.2 million US$ by the end of 2026, in other words, growth at a rate of 14.8% CAGR of during 2021-2026.
My name is Vivek Rawool. I am extremely motivated to constantly develop my skills and grow professionally. I have completed my BE Mechanical Degree from Mumbai University and currently working with Paramount India as a Sales and Marketing Engineer. I also do Share market trading and investment.
