By Rup Narayan Dhakal : Pokhara–Hydrogen, the first element on the periodic table, is an incredibly reactive and abundant element in the universe. However, it does not exist independently in the environment; instead, it remains combined with other elements. The production of hydrogen typically involves methods like heating and electrolysis, with water (H2O) being a common source containing two hydrogen atoms and one oxygen atom.
Depending on the process used to produce hydrogen, different types of energy are generated. Gasification of coal produces brown or black energy; nuclear power-produced hydrogen is termed pink energy, while the use of natural gas and fossil fuels results in gray energy. An environmentally conscious approach involves fossil fuel carbon capture and storage technologies, giving rise to blue energy. However, the large carbon footprint associated with these processes poses a challenge in mitigating the impacts of global warming and climate change. To combat this, green energy, derived from renewable sources like electricity, solar power, or wind power, plays a vital role by significantly reducing greenhouse gas emissions and carbon footprints.
Hydrogen fuel proves especially valuable for long-haul transportation in trucks, shipping, and air services. Unlike batteries that require frequent recharging during long-distance travel, hydrogen offers longer storage capacity, making it more practical for these applications. In sectors like steel, cement, and fertilizer production, green hydrogen adoption leads to zero carbon emissions, making it a crucial player in the future economy. Some major automakers, such as Tata, Toyota, and Hyundai, have already developed hydrogen-powered vehicles.
Fuel cells play a central role in utilizing hydrogen as an energy source. These cells combine oxygen from the air with hydrogen, producing both water and electricity. The process involves splitting hydrogen molecules into electrons and hydrogen ions, with the latter passing through a membrane and creating an electric current in an external circuit. At the cathode side, the electrons, hydrogen ions, and oxygen combine, forming water.
Green hydrogen cars, while promising, currently face higher production costs due to the expense of green energy. On average, producing 1 kg of green hydrogen, which provides about 100 km mileage, costs around 5 to 6 US dollars, while gray hydrogen costs around 2 dollars. Green hydrogen vehicles are currently priced at around 60,000 dollars in the global market. Additionally, the limited availability of refueling stations poses a challenge, with only a few hundred stations worldwide as of 2020. To encourage the development of more refueling stations, government subsidies are necessary.
One of the hurdles faced by hydrogen as an energy source is its poor volumetric energy density, necessitating high-pressure compression for practical application, thus making transport and storage challenging. Nevertheless, green hydrogen holds great potential for civilian transportation and passenger vehicles, positioning hydrogen as a crucial fuel for the 21st century. It offers a promising path towards achieving the global goal of net-zero or zero carbon emissions by 2050. However, further research, technological advancements, and cost-reduction efforts are necessary to make green hydrogen more viable, cost-effective, and widely accessible. Its role is instrumental in realizing a carbon-free and energy-independent future. In conclusion, hydrogen stands as a beacon of hope for the future, rather than mere hype.