O nce again, South Korean President Moon Jae-in has instilled a new hope within the Korean people on his New Year journey to the industrial outpost of Ulsan. In the midst of the severe cold filled with micro dust, President Moon put extra emphasis on the hydrogen economy for the revitalization of the Korean economy. As he has inspired a hope for peace and reunification on the peninsula by inviting North Korean delegates to the PyeongChang Winter Olympic Games a year ago, his new aspiration for a hydrogen economy is a refreshing economic agenda eager to reconstruct trust and faith in his government.
The concept of a hydrogen economy is not an entirely new idea. Already proposed by a number of scientists in the 1970s to diminish the negative effects of hydrocarbon fuels emitting harmful carbon compounds such as carbon dioxide, carbon monoxide, or unburnt hydrocarbons, former U.S. President Bush, Jr. also mentioned the importance of a hydrogen economy in his 2003 State of the Union Speech. Iceland and Australia have already adopted a series of national policies to utilize hydrogen energy. And yet, President Moon’s anointing of the hydrogen economy for the future of the Korean economy with silver lining remarks are so unprecedented and unparalleled as to be taken lightly.
A key element of the hydrogen economy is to use hydrogen instead of hydrocarbon fuels such as petroleum as a prime source of energy for the entire society. Traditional hydrocarbon fuels (oils and coals) have two critical handicaps: they create pollution and they are scarce. Hydrogen can be an environmentally cleaner source of energy to end-users without releasing pollutants such as particulate matter or carbon dioxide at the point of end use, and the supply of hydrogen is as bountiful as water. Although hydrogen has less volume energy density than other competitors, it has very high weight energy density, meaning it creates higher energy by weight than other fuels.
There is no doubt that hydrogen has a very strong merit as a clean energy source. But there are a number of fundamental technical and economic barriers to be overcome for the practical use of hydrogen: technical and economic aspects of its production, carriage and storage, transportation, as well as safety.
The first challenge is related to the production of hydrogen. Hydrogen molecules are not available on earth in convenient natural forms because it is bonded to oxygen in water. Therefore, extraction or manufacturing hydrogen does require a hydrogen carrier such as a fossil fuel or water. Basically, hydrogen can be produced in four different ways: the reforming or refining of carbon-fuels (the so-called brown hydrogen), water-electrolysis (green hydrogen), and as a byproduct from oil wells or industrial processes (grey hydrogen). Hydrogen is already being massively produced for commercial use. But it is produced either for producing fertilizer, usually called the Haber process producing ammonia, or for the hydrocracking process facilitating extraction of lighter fuels from heavier sources. Almost all hydrogen for these uses come from fossil fuels, creating environmental hazards. But these uses are not included in the hydrogen economy. The hydrogen economy refers to the production of hydrogen for the sole purpose of clean energy use, most notably for vehicles and local electricity. So, the most desirable way to produce hydrogen is through an electrolysis process, decomposing water into hydrogen molecules and oxygen with electricity. But so far, it seems economically less than 80 percent efficient, making it economically so unfeasible that it takes up only 4 percent of the world’s hydrogen production.
The second challenge refers to the storage and transportation of hydrogen. Hydrogen is very light and requires an enormous amount of energy to be pressurized or liquefied (requires –250°C). Besides, hydrogen causes metal containers to be easily broken and corroded. Hydrogen can be simply stored and carried by making hydride (i.e., hydrogen-compound), but all of these methods require the reverse process of making hydride into hydrogen, which necessitate additional energy and costs.
The third challenge is the infrastructure problem. A hydrogen infrastructure refers to an industrial hydrogen pipeline system and hydrogen filling stations like those found on a hydrogen highway. Hydrogen stations which were not situated near a hydrogen pipeline would get the supply through hydrogen tanks, compressed hydrogen tube trailers, liquid hydrogen trailers, or liquid hydrogen-tank trucks. Bringing hydrogen to individual consumers would require a massive over-haul of the fuel infrastructure.
The fourth challenge is linked to the fuel cell. Much of the interest in the hydrogen economy is associated with the use of hydrogen fuel cells to power electric cars. Current hydrogen fuel cells suffer from a low power/weight ratio. If a practical method of hydrogen storage is developed and fuel cells become cheaper, they can be economically viable to power hybrid fuel cell/battery vehicles, or purely fuel cell-driven ones. The economic viability of fuel cell powered vehicles will inversely depend on the price of the hydrocarbon fuels. Safety is another important concern. Hydrogen is very explosive, and ignitable with the air of almost all gases. So a hydrogen leak will most likely lead to an explosion, not a mere flame, when a flame or spark ignites the mixture. This makes the use of hydrogen particularly dangerous in highly populated and enclosed areas such as tunnels or underground parking. Pure hydrogen-oxygen flames burn in the ultraviolet color range and are nearly invisible to the naked eye, making human lives more vulnerable.
All of these well-known challenges are ahead of Korean economy. Many are either hesitating or dubious about its success. But it should be remembered that in the early 1980s, Samsung ventured into the then untrodden world of semi-conductors. Almost everyone objected to the project except for the company’s late chairman Byung Chul Lee, who insisted on investing in the new venture. It surely is not easy, but is well worth giving a try.
By Professor Se Don Shin
Dean, Sookmyung Women’s University
The opinions expressed in this article are the author’s own and do not reflect the views of KOTRA