“What are they going to burn instead of coal? Water. Water decomposed into its elements by electricity will one day be used as fuel.” More than150 years ago, in 1875, Jules Verne foresaw in his novel 'The Mysterious Island' the use of what is currently considered the great ally in the decarbonization of the energy sector: hydrogen.

In recent years, the possibility of using hydrogen as a viable alternative in global energy production has gained greater visibility. According to data from the International Energy Association (IEA), global hydrogen consumption currently exceeds 75 million tons per year. It is estimated that by 2050, 6% of the world's final energy consumption will be hydrogen-related, as stated by data from the International Renewable Energy Agency (IRENA). Not all types of hydrogen are environmentally friendly; one of the solutions that we have been hearing about the most lately is green hydrogen, also known as renewable hydrogen or e-Hydrogen.

What exactly is it and why is it considered an innovative clean energy technology?

What makes it clean and unique

Hydrogen is the most abundant chemical element in the universe: however on Earth, it only exists in combination with other elements. For this reason, in order for it to be used in energy applications, it is necessary to separate hydrogen from other molecules, and this requires the use of large amounts of energy and high production costs.

The energy used to extract hydrogen can pollute the environment. The vast majority of hydrogen is produced thanks to hydrocarbons, natural gas and coal, making its production an abundant source of carbon dioxide (CO₂) emissions. A few years ago, hydrogen began to be produced from renewable energy sources, such as the sun and wind, through a process known as electrolysis. Here hydrogen is separated from the oxygen in water using renewable energies. Practically no emissions are generated during the production of this so-called "green hydrogen" or "clean hydrogen."

This technology therefore offers an inexhaustible source of clean and sustainable energy which, as the study ‘Hydrogen Roadmap Europe: A sustainable pathway for the European Energy Transition’ points out, could save more than 560 million tons of CO₂: that is the amount produced when hydrogen is created using fossil fuels (such as in the case of gray hydrogen). This technique represents an alternative that is set to be a key player in the decarbonization of the energy sector and is thus in line with European targets for neutral emissions by 2050.

From gray to green: novel hydrogen applications

Despite the many benefits of this new type of clean energy, energy from renewable sources (which is essential in generating green hydrogen) involves considerable financial investment, making it very expensive to obtain. The reason why green hydrogen could play a fundamental role in the decarbonization of the planet is because it is considered to be the only 100% sustainable form of hydrogen and has many promising applications.

• Energy storage: Besides being easy to store, hydrogen is seen as one of the most cost-effective systems for long-term stationary energy storage, according to DNV GL's research paper 'The promise of seasonal storage'.
  
• Transportation: Vehicles that run on this clean energy have a hydrogen tank that is directed to the fuel cell, where electricity is generated to power the engine. The so-called Fuel Cell Electric Vehicle (FCEV) represents a revolutionary technology within transportation as it uses fuel with a zero-CO₂ footprint. According to the IEA, hydrogen-powered vehicles are joining the boom in electric and hybrid vehicles, which are considered zero-emission vehicles.
  
• Industry: It can be used in the refining industry as well as in the chemical and metallurgical industries. Green hydrogen, unlike the gray (fossil fuel) or blue (hybrid) varieties, also helps boost renewable energies in the energy mix and can decarbonize energy-intensive industries.
  

Enel and green hydrogen: together in the future of energy decarbonization

In its seventh Sustainable Development Goal (SDG) – “Affordable and clean energy,” – the United Nations (UN) stresses that the world must start afresh, and energy will be one of the key ways for achieving this. In order to accomplish this goal, the distribution of this resource must be equitable and, above all, sustainable. Most countries, institutions, companies and experts who advocate for the environment and the future of our planet agree on this – so does Enel.

"Enel has long since decided to put environmental issues at the heart of its strategy: renewable energies, domestic and industrial energy efficiency and the circular economy are at the center of all our actions,” says Ernesto Ciorra, the Group’s Chief Innovability^® Officer. We are developing numerous projects to produce green hydrogen, installing electrolyzers that are powered by renewable forms of energy and placed near the points of consumption. In this way, Enel will supply green hydrogen to its customers while minimizing the need for transport infrastructure and contributing to the stability of the electricity system. "We aim to reach more than 2 GW of capacity by the end of the decade,” Ciorra adds.

Enel is also involved in several international initiatives that promote the development of green hydrogen. As a company, we take part in various policy consultations organized by the European Commission, as well as in international round tables and working groups, such as the Renewable Hydrogen Coalition, the CEO Alliance, and the Clean Hydrogen Alliance. Furthermore, Enel is leading numerous projects related to this new form of energy at international level, including some in Italy, Spain, Chile and the United States.

It is not yet clear whether other predictions from science fiction literature or by Jules Verne will come true. What we do know is that there are still challenges ahead which we will need to overcome in order to consolidate green hydrogen as a source of energy that can contribute to a more sustainable world.