The use of alternate sustainable fuels has been a subject for debate for decades in the energy sector; without a doubt, the most exciting prospect is hydrogen. However, there are a lot of challenges to be handled, with high production costs but huge prospects in terms of sustainability.
The concept of using hydrogen as an energy source is not new, but the production process is difficult to implement . Technical issues, such as safety and high production costs, as well as environmental impact, have frequently stymied development. In fact, despite its abundance in the cosmos, hydrogen is not always easy to locate in pure form, and hence must be extracted and stored using processes that define prices and sustainability. It's also worth noting that hydrogen takes on varied colours depending on where it comes from:
Grey hydrogen is extracted from coal or natural gas, and while its extraction costs are lower, the pollutant charge is unquestionably larger, so even if it is the most economically viable form, it is undeniably not environmentally sustainable.
Blue hydrogen, as a result of this extraction method, has the unique property of retaining carbon rather than dispersing it into the atmosphere, making it more environmentally friendly but slightly more expensive to extract.
Green hydrogen is the most environmentally friendly. It is distinguished by a completely distinct extraction process based on water electrolysis. It a very complex approach that splits water into oxygen and hydrogen with a lot of energy. However, if it is derived from renewable resources, the carbon footprint is nearly negligible.
Green hydrogen is currently a niche product due to two specific factors limiting its development. The first is the requirement for huge amounts of energy to be derived from renewable sources. Although the energy revolution is already underway, current renewable energy sources are unable to provide the required amount of electricity. The second impediment is that green hydrogen production costs are twice as high as blue hydrogen production prices.
The advantages, on the other hand, are obvious in terms of environmental sustainability. Electrolysis, unlike renewables (which are subject to weather and light conditions), can operate 24 hours a day and hydrogen can be stored and used as needed. According to the European strategy, by 2050, appropriate instrumentation will have been developed to create a sufficient number of electrolysers to make hydrogen and convert several sectors that are currently difficult to decarbonize. However, we still have a long way to go as we continue to focus on manufacturing grey and blue hydrogen, which has considerably lower production costs and technology. Grey hydrogen costs between 1 and 2 euros per kilo, whereas green hydrogen can cost up to 9 euros per kilo at peak times. The decision to focus on green hydrogen is critical, especially in view of the global climate catastrophe and the goals that the European Union has set for itself to address it. However, the option is not without its drawbacks, which should not be overlooked; however, these obstacles are not insurmountable - they are technological, economic, and regulatory issues - and with research, the proper answers can be found.
Iridium in particular, which is required to construct the electrolysers, is a serious issue. There are various electrolysis methods currently in use; the most common and well-developed are the alkaline electrolytic cell (AEL) and the proton exchange membrane (PEM) cell, which is more efficient than the AEL and designed to overcome the latter's technological limitations. Alkaline electrolysers have few problems with raw materials; nickel, platinum, and cobalt are employed in the stacks, materials that are not common and do have a limited supply. The PEMs, on the other hand, require not just platinum but also iridium, one of nature's most scarce materials. South Africa produces 85 percent of all iridium, and there are natural monopoly issues there. There is no specific production statistics, but the US Geological Survey's most current estimates put it between 5.2 and 7.7 tons per year, and producing it entails CO2 emissions, which must be considered if the extraction is effective in combating the climate emergency. The market for iridium is "illiquid" and extremely volatile.
While the International Renewable Energy Agency is hopeful about the long-term development of PEM technology, it warns that a lack of materials could stymie cost reduction and market expansion. Furthermore, the European Commission's "Fit for 55" package, which has yet to be approved by the Council and Parliament, calls for the end of the production of gasoline and diesel cars in 2035, with electric and hydrogen as the primary substitutes. A replacement that will be difficult to obtain in the short term, because with present global iridium and platinum output, it would be impossible to get over 10% without compromising its use in other industries. With today's technologies, there will be insufficient material to manufacture PEM-type electrolysers, and rising costs will only partially enable the extraction of material from locations where it is now not economically viable. If there are no technical changes, all of this will be achievable. These solutions all have one thing in common: study. It is critical that we continue to research the economic and technological potential in order to develop a green energy market that benefits the environment first and foremost.
Another obstacle, in addition to rare metals, is renewable energy. Green hydrogen cannot be produced without green energy. Because renewables are by definition random and not continuous, it is common to couple these plants with renewable non-programmable renewables in order to maximize the hours of operation of an electrolyser. We would need dedicated plants of at least 10 GW of new capacity, and considering the long time it has taken for renewable energy technologies to mature, there is still a lot of work to be done. The fundamental focus is to unleash all renewable energy investments, ensuring that it restarts with massive levels of development, while discouraging and modifying incentive structures. Green hydrogen must become a basic element. A cost decrease that makes production competitive will surely be critical to achieve sustainable production.
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