Green hydrogen is a form of hydrogen produced through a process called water electrolysis, which uses electricity from renewable sources, such as solar or wind power. This technology is considered a promising alternative to fossil fuels, since the production of green hydrogen is virtually carbon-free. However, there are some green hydrogen problems that must be taken into account to consider it as an official alternative to fossil fuels.
In this article we are going to tell you about the main problems of green hydrogen, its characteristics, advantages and disadvantages.
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green hydrogen production
Hydrogen has the ability to store energy that can be used when needed. This is nothing new. But hydrogen is not alone on Earth. It is always attached to other molecules to form elements. The simplest: water and its well-known molecular formula H2O. Two hydrogen atoms are bonded to one oxygen.
But it is also found in fossil fuels such as methane or liquefied petroleum. At the moment, 99% of the hydrogen in Spain comes from these fossils. According to the International Energy Agency, the global procurement of hydrogen generates about 900 million tons of carbon dioxide emissions each year.
To collect hydrogen from a clean feedstock like water, it is necessary to apply an electrical current to it to separate its elements and keep the hydrogen isolated. If the electricity used in the electrolysis process comes from renewable sources, such as solar panels or windmills, it is called green hydrogen. By releasing its stored energy, it does not emit greenhouse gases. As such, it addresses the climate crisis in good faith.
If the electricity generated by photovoltaic parks or wind turbines is used to produce hydrogen separated from water, this will act as fuel. In other words, this energy (electricity) is not lost or used when it is produced: hydrogen can then be released through engines, machinery or batteries with the right technology.
The Ministry of Ecological Transition highlights that its role as seasonal storage will be key, considering the use of surplus renewable energy in an increasingly renewable electricity system. This will be one of the solutions to manage electricity production when renewable resources are chronically scarce.
Green hydrogen problems
The problem has to be the cost and the difficulty of production. First, although hydrogen is one of the most abundant elements on Earth, it is not readily available because it is not found in isolation in nature, but rather it is produced from other substances that contain hydrogen, such as water, coal, and natural gas. The ideal way to produce it would be to obtain it directly from water (which is present in 70% of the earth's surface) through a process called electrolysis, which consists of the decomposition of water molecules (H2O), decomposed into oxygen (O2 ) and hydrogen (H2).
However, this is usually an expensive process that requires a lot of electricity (not from renewable sources in most cases) to power the electrolyzers. The difficulty of obtaining 100% clean hydrogen has led producers to classify the resulting products according to their sustainable value. Thus, gray hydrogen, which is currently the most widely used, is the least environmentally friendly, since its production continues to require fossil fuels.
As an alternative, "blue or low carbon hydrogen" still requires fossil fuels but emits less carbon because it is removed through a process known as "capture and storage." The greenest option is “green hydrogen” produced from renewable energy, a 100% sustainable alternative but the least common on the market.
How much does it cost to produce hydrogen?
Research recently published in the specialized journal Nature Energy has set out to quantify the cost of producing hydrogen from electricity (through electrolysis) to determine if it is a commercially viable alternative. To do this, the researchers collected data on the costs and prices of hydrogen and compared it with electricity prices on the wholesale market and full-year data on wind power generation in Germany and the United States.
He concluded that a hybrid system (generating hydrogen from renewable energy, typically wind or solar) it could be profitable from 3,23 euros per kilogram. However, the same study notes that the cost of electrolyzers is falling dramatically, which could significantly reduce the cost of producing hydrogen from renewable sources, representing a "full decade and a half" in terms of energy sustainability.
In fact, according to Javier Bray, president of the Spanish Hydrogen Energy Association, it is already fully feasible. Electrolysis is the second method in the world to produce hydrogen on an industrial scale. Furthermore, it is a clean method and its cost is directly proportional to the electricity used in its production. For the expert, values lower than 2,5 cents per kWh give us prices of about 2,5 euros per kilogram, which makes it a viable solution for the decarbonization of sectors such as industry, transport or energy.
Although it is currently the least produced on the market, it has great advantages that reside in its great potential:
- Emission reduction: The production and use of green hydrogen does not emit carbon dioxide or other local pollutants, which directly contributes to the reduction of greenhouse gas emissions and helps in the fight against climate change.
- Efficient energy storage: Green hydrogen can be easily stored, making it an attractive solution for storing renewable energy at times when demand is low and generation is high.
- numerous applications: It can be used to power fuel cell electric vehicles, as fuel for electrical generators in industries, and as a raw material in the production of chemicals and fertilizers.
- Energy independence: By relying on renewable energy sources for its production, green hydrogen reduces reliance on imported fossil fuels and the price fluctuations associated with these non-renewable resources.
- Clean fuel for the industry: Green hydrogen offers a clean and sustainable fuel option for the industry, thus reducing its environmental impact and contributing to the transition towards a low carbon economy.
I hope that with this information you can learn more about the problems of green hydrogen, its characteristics and the advantages it has.