The Green Hydrogen Revolution

4 December, 2019

Hydrogen is the most abundant element in the universe. But it’s hard to find it in a free state. It must be extracted from other sources such as water, coal, biomass or natural gas.

The variety of options for its production and collection, together with its high efficiency in fuel cells and storage capacity over long periods, make it a highly valued resource in all sectors of society.

There are different types of hydrogen, depending on sources and production methods.

  • Grey hydrogen is generated through natural gas steam reforming. This process produces CO2, so it is not an emission-free process.
  • Blue hydrogen is obtained in a similar way to grey hydrogen, but in this case the CO2 is captured rather than emitted into the atmosphere, so it is considered a low-carbon process.
  • Renewable hydrogen or green hydrogen is produced by electrolysis of water from renewable electrical energy, such as solar or wind. This process does not emit CO2 and transforms water into hydrogen and oxygen molecules. Thus, it is an effective solution for promoting the decarbonisation of all sectors (mobility, industry and services).

What are its benefits?

Green hydrogen has countless benefits, such as:

  • It is obtained from elements as abundant as water and renewable electrical energy
  • It is 100% clean energy. In all its production process, CO2 emissions are zero.
  • It offers energy stability, as it enables energy storage, thus offsetting intermittent generation from renewable electricity and reducing energy discharges
  • It can be transported through the existing gas infrastructure mixed in a certain measure with natural gas
  • It can be used to generate synthetic gas which, for all intents and purposes, is comparable with natural gas
  • It has multiple applications. In addition to domestic/commercial consumption and mobility, it can be used as a raw material for decarbonisation in the industrial and chemical sectors, especially where electrification is not feasible today or where it is already consumed as grey hydrogen

The capacity of hydrogen to manage renewable power, something that is not possible on a large scale today, would guarantee the security and reliability of the energy supply in a future in which renewable energies acquire a more significant role in the power generation mix. This increase will lead to large electricity surpluses and one of the most efficient ways of storing this surplus will be by the production of green hydrogen. This process is called ‘power to gas’technology (a concept that refers to the transformation of electricity into gas, hydrogen in this case).

By 2030, hydrogen is expected to be capable of powering between 10 and 15 million passenger cars and half a million trucks

Where is it used?

Green hydrogen, produced by electrolysis, can contribute to the decarbonisation of three major sectors:

  • Transport.  By 2030, hydrogen is expected to be capable of powering between 10 and 15 million passenger cars and half a million trucks. Hydrogen fuel cell electric vehicles are an alternative to battery-powered electric vehicles. They offer greater range, faster recharging times and therefore allow recurring use of the vehicle, something for which current batteries are more limited. In addition to its use in light vehicles, last-mile and heavy road transport, hydrogen can also be used as fuel for rail and sea transport, two sectors where electrification is not technically feasible at present.
  • Industry. Large amounts of hydrogen are currently used in various industrial sectors, but this is hydrogen obtained from fossil fuels (grey hydrogen). Replacing it with green hydrogen would greatly reduce the CO2 emissions associated with these processes and thus decarbonise industrial sectors such as refineries, chemicals and fertilisers.
  • Residential. In addition to industry, this renewable gas can be used for domestic and commercial consumption. Unlike renewable electrical energy, hydrogen can be easily transported and stored in the existing gas pipeline, without the need for significant additional network investments.

The main challenge is to make green hydrogen a competitive technology

What are the challenges ahead?

Green hydrogen is today a developed and proven technology. The main challenge is to make green hydrogen a competitive technology. The key to this is to upscale it to industrial production. In this sense, it is essential to invest in innovation and incentivise R+D+i to accelerate the learning curve and economies of scale in investments in generation plants.

Only by defining medium- and long-term guidelines for action, as is already being done with renewable electricity, will technological neutrality be achieved in the energy transition, and the system be supplied with all the necessary tools to guarantee the security and flexibility of the national and European energy system.

With the aim of introducing large amounts of hydrogen into existing infrastructures in the future, a guarantees of origin system needs to be developed to ensure the traceability and renewable nature of the hydrogen injected.

What about developing an agreed plan to promote hydrogen in Spain? Yes, this must be another challenge to be addressed. A plan that includes objectives and actions for the medium (2030) and long term (2050), in accordance with the sustainability objectives proposed by the National Integrated Energy and Climate Plan (PNIEC), in line with the national hydrogen plans already being published by most European countries.

Green hydrogen is a technological opportunity that, as a country, we must take advantage of

Green hydrogen is a technological opportunity that, as a country, we must take advantage of. Spain is in a privileged position for its large-scale production, due to its capacity to generate renewable power. It also has an infrastructure network already capable of transmission and storage, which will mean that the energy transition can take place at the lowest possible cost, a fundamental factor for ensuring that this process is fair and inclusive and that it guarantees the supply and flexibility of the energy system.