Hydrogen Underground Storage : Status of Technology and Perspectives

Author: Carlo Cappellani – Senior Geoscientist

1  Hydrogen Underground Storage : Status of Technology and Perspectives

Hydrogen will play a key role in the development and transformation of future renewable energy systems. H2 has many benefits, can be generated by well-established and emerging technologies and can be used in a variety of end-use energy and transport processes. H2, as a fuel source, has long been identified as a critical step toward a low-carbon, and eventually zero-carbon, energy society. Hydrogen storage is an essential element of an integrated energy system and hydrogen economy. As hydrogen demand and production are growing, underground storage is emerging as a relevant, large-scale solution. While in recent years a lot of attention has mainly been on hydrogen supply and transmission infrastructure, there is the need for underground hydrogen storage to balance and ensure the resilience of a future energy system that relies significantly on renewable energy sources. Hydrogen can be physically underground stored using a method which has already proven its worth and Carbon Geo Sequestration (CGS) and natural gas are essential analogs for H2 storage. Natural gas storage in underground facilities can be dated back to 1916 when it was stored in geological formations. According to many authors, Ontario gas field (Canada) is considered the first successful underground storage project (Taylor et al., 1986). However, certain operational differences (physical and chemical properties) unique to H2 must be acknowledged for effective operation (Iglauer, 2017). Higher demand means there is going to be a need for increased storage capacity and the solution to this challenge is to utilize earth underground reservoirs. Underground reservoirs, such as salt caverns or porous rocks, offer giant capacities to store billions of cubic meters of hydrogen at high-pressures. Although the existence of few Underground Hydrogen Storage (UHS) sites, up till now, little is known about how hydrogen behaves in the subsurface and, current studies are investigating not only how it behaves in the subsurface but also what kind of environment – type of subsurface – would be the right reservoir to store it at a given quantity and scale. Also, to consider challenges of containing hydrogen tiny molecules inside the reservoirs, maintaining its purity, and operating the system within safe mechanical cyclic loading. Considering underground hydrogen storage, an integrated multidisciplinary approach is required, combining several specialists and disciplines (e.g. fluid mechanics and rock mechanics, etc.). Also, integrating laboratory discoveries with numerical modelling will provide solutions to make this technology ready for field deployment within next year


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Natural Hydrogen: Promising opportunities for Exploration & Production

Author: Carlo Cappellani – Senior Geoscientist

1          Introduction


The global energy sector is transforming and hydrogen (the most energy-rich gas) is likely to play an increasingly prominent role as a clean energy carrier. Many countries have identified hydrogen as a key pathway to decarbonise their transport, industry processes, heating and energy storage sectors.

Hydrogen is almost exclusively manufactured for industrial use, with around 840 Bm3 per year being produced worldwide (Wood Mackenzie 2021).

It can be produced artificially via a variety of different pathways and the primary methods for production of hydrogen with low carbon emissions being

  1. water electrolysis using renewable energy (green hydrogen)
  2. steam reformation of natural gas paired with carbon capture and storage (CCS; blue hydrogen)
  3. coal gasification combined with CCS (also blue hydrogen).


  • the majority of produced hydrogen originates from hydrocarbon-based feedstock without CCS (grey hydrogen) since the economics for the electrolytic production of green hydrogen (0.1% of total H2 production) requires improvement (Wood Mackenzie 2021).
  • For a large-scale hydrogen industry to develop, hydrogen storage is key and hydrogen storage in salt caverns is considered the most promising approach for large-scale seasonal storage (HyUnder 2013; Caglayan et al. 2020).


Figure 1 Primary methods for hydrogen production


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Big Data in Oil and Gas Industry

Author: Elvirosa Brancaccio – Serintel Srl – Rome (Italy)


1          Introduction


Big Data or Big Data analytics refers to a new technology which can be employed to handle large datasets which include six main characteristics of volume, variety, velocity, veracity, value, and complexity.

With the recent advent of data recording sensors in exploration, drilling and production operations, oil and gas industry has become a massive data intensive industry.

Analyzing seismic and micro-seismic data, improving reservoir characterization and simulation, reducing drilling time and increasing drilling safety, optimization of the performance of production pumps, improved petrochemical asset management, improved shipping and transportation, and improved occupational safety are among some of the applications of Big Data in oil and gas industry.

In fact, there are ample opportunities for oil and gas companies to use Big Data to get more oil and gas out of hydrocarbon reservoirs, reduce capital and operational expenses, increase the speed and accuracy of   investment decisions, and improve health and safety while mitigating environmental risks.

big data

Figure 1 Big Data in Oil and Gas Exploration and Production

One of the key enablers of the data-science-driven technologies for the industry is its ability to convert Big Data into “smart” data.  New technologies such as deep learning, cognitive computing, and augmented and virtual reality in general provide a set of tools and techniques to integrate various types of data, quantify uncertainties, identify   hidden   patterns, and   extract useful information enormously reducing the data processing time.  This information is used   to   predict   future   trends, foresee behaviors, and answer questions which are often difficult or even impossible to answer through conventional models.


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Low Motion Floating Production Storage Offloading (LM-FPSO): Evolution of Offloading Production Systems

Authors: Marco Cocchi – Researcher – Campus Bio-medico University of Rome
                Leone Mazzeo – Researcher – Campus Bio-medico University of  Rome



1          Introduction


Oil & Gas industries have moved in deeper, more remote and technically demanding regions in the last 30 years. With increasing technical complexity of the extraction facility, the fixed cost of the Oil & Gas upstream complex also increases, but in the persistent lower-for-longer price environment there is continuing pressure to develop these fields safely while reducing CAPEX and OPEX costs.

FPSO technology seems to be promising in offering a flexible solution to explore remote Oil fields while in maintaining competitive costs. Nonetheless, Semisubmersible units, SPAR platforms and tension-leg platforms (TLPs) are also common in deepwater regions. TLPs, in particular, find application in up to 1,500m-deep water wells, but FPSO has the advantage to offer the required onboard storage capacity and offloading capability without employing a separate storage vessel or infrastructure.

The high dynamic motion, generated by the rough sea condition to which FPSO units are exposed when operating in remote sea areas, makes the Riser System design more challenging. In fact, it plays a fundamental rule in determining the feasibility of the extraction of hydrocarbons exploiting remote region resources. Thus, the development of a low-motion FPSO enables the utilization of conventional riser systems (such as steel catenary risers and top-tensioned risers). The use of conventional riser technologies, is also able to improve the life-cycle and reliability of a FPSO facility: the realization of a simple and effective installation (by the means of an additional facility structure) that is able to oppose to the high dynamic forces that rough sea environment exerts on the floating structure, is a technological step change, needed to open up less accessible or economically cost-prohibitive fields.


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The Role of Natural Gas in the Energy Transition Phase

Authors: Marco Cocchi – Researcher – Campus Bio-medico University of Rome
                Leone Mazzeo – Researcher – Campus Bio-medico University of  Rome


1         Introduction


The rapid growth of the world population driven by the development of the industrial sector, have led to an increase of the anthropogenic greenhouse gas emissions. It has been detected an unprecedented, in at least the last 800,000 years, concentration of carbon dioxide (Figure 1‑1) in the atmosphere. Such event, together with other anthropogenic drivers, have been related as the main cause of the phenomena of the “global warming” observed since the mid-20th century.


Global anthropogenic CO2 emissions

Figure 1‑1 Global anthropogenic CO2 emissions[1].


In order to face the issue raised from the considerations about CO2 concentration, the first worldwide agreement on greenhouse gas emissions was signed in April 2016. The 196 countries responsible for 55% of total CO2 emissions agreed, at the Conference of the Parties in November 2015, to commit to cap global warming at a maximum 1.5°C (referred to the global land-ocean mean surface temperature, GMST), a more challenging target than the 2°C cap originally proposed in the Paris World Climate Conference. Given this commitment, signatory countries need to review their energy strategies in order to reduce emissions by actively promoting low carbon economy policies[2].

Natural gas is a fossil gas mixture consisting mainly of methane (C1). The remainder is heavier hydrocarbons: ethane (C2), propane (C3), isobutane (iC4), n-butane (nC4), and small amounts of heavier components down to C7s. The typical values of the percentage of methane mole fraction in natural gas may vary from 87% up to 97%[3].

Among all the fossil primary energy sources, natural gas presents the highest hydrogen to carbon ration. This characteristic is of extreme importance since leads the following two main properties:

  • The highest lower heating value expressed in MJ/kg respect to all the others fossil fuels. (As described in the picture below[4])
  • The lowest mass of CO2 produced per mass of combustible.


Lower heating value [MJ/kg] for different types of hydrocarbons
Figure 1‑2 Lower heating value [MJ/kg] for different types of hydrocarbons[5].

According to the proprieties described above, natural gas plays a fundamental role in the fight against climate change. The substitution of high carbon content fossil fuels, such as coal, with natural gas, may represent the first step forward the decrease of CO2 emissions.

The main sectors that will immediately benefit of replacing low hydrogen to carbon fuel with methane in terms of CO2 emissions are:

  • Energy production. All the thermo-electric energy plants belong to this sector. They may easily introduce methane as fuel in the burner for the production of high pressure steam. This strategy, adopted already by many companies, reduces CO2 emissions saving operative costs on the post-combustion carbon capture unit.
  • Transportation. On road transportation is already affected by the presence of vehicles fed by methane. In this case engines are designed to host such type of fuel and this constitutes a positive direction for the reduction of CO2

It is clear that the substitution of “conventional” fuel with methane is just a temporary solution, a clever way to “take time” establishing a transition phase, until the worldwide development of the zero-emission (renewable) energy sources will take place.


[1] “Climate Change 2014 Synthesis Report Summary Chapter for Policymakers,” 2014.
[2] https://safeonline.it/wp-content/uploads/2016/09/Articolo-Accenture-2016.pdf
[3] https://www.uniongas.com/about-us/about-natural-gas/Chemical-Composition-of-Natural-Gas
[4] https://www.engineeringtoolbox.com/fuels-higher-calorific-values-d_169.html
[5] https://www.engineeringtoolbox.com/fuels-higher-calorific-values-d_169.html


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Innovation and New Technologies in the Upstream Oil & Gas Industry

Authors: Marco Cocchi – Researcher – Campus Bio-medico University of Rome
                Leone Mazzeo – Researcher – Campus Bio-medico University of  Rome



1          Introduction


Oil & Gas reservoir research and exploration requires the utilization and adaptation of a large number of different technologies spread over numerous engineering fields. Because of the intense resource involved in such operation, the Exploration and Production sector (E&P) results to be a power-demanding field and particular attention should be paid to make it smarter and more efficient.

In the research of technology updates, upstream, as well as downstream, Oil & Gas industry has always been seeking out external innovations even in the field of informatic technologies and robotics.


Work-class ROVs

Figure 1: Work-class ROVs: the innovative remote-controlled robots for subsea operation[1]


In Figure 1 a work-class ROV (remote operated vehicle) for subsea exploration is reported during its assembly phase. ROVs are made from robotic arms, known as manipulators, a camera, for subsea environment visual analysis, electrical drivers for motion control and batteries or external cables for communication and power delivery. ROVs for exploration were introduced during the ‘70s and represented a significant technology update in their field: thanks to the fact that they can be designed to operate at very high pressure and low temperature conditions, with the respect to human operators, they allowed to discover a high number of new oil fields that previously were thought impossible to be investigated, increasing the opportunities for Oil & Gas companies. The introduction of ROVs also decreased the cost of the exploration operations and, on top of the economics aspect, they increased the safety by substituting and replacing human operators.

ROVs represent also an example of technology transfer from external sectors (in this case the military sector) to upstream Oil & Gas operations. Technologies that come into the Oil & Gas sector often enter into a prolific chain of innovation and become refined commercialized. That was also the case for ROVs, that having been incorporated for years in the Upstream sector, found new application for scientific research in marine biology and they have been used over the years to search for famous shipwrecks and discover new marine species.

In the following paragraphs, some of the most important new technologies in the E&P sector will be presented and discussed.


[1] Source: “https://pubs.spe.org/en/jpt/jpt-article-detail/?art=5153”


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Current Trends in Artificial Intelligence (AI) Application to Oil and Gas Industry

Authors: Marco Cocchi – Researcher – Campus Bio-medico University of Rome
                Leone Mazzeo – Researcher – Campus Bio-medico University of  Rome


1          Introduction

In recent years, artificial intelligence (AI), in its many integrated flavors from neural networks to genetic optimization to fuzzy logic, has made solid steps toward becoming more accepted in the mainstream of the oil and gas industry.

On the basis of recent developments in the field of Oil & Gas upstream, it is becoming clear that petroleum industry has realized the immense potential offered by intelligent systems. Moreover, with the advent of new sensors that are permanently placed in the wellbore, very large amounts of data that carry important and vital information are now available.

To make the most of these innovative hardware tools, an operator intervention is required to handle the software to process the data in real time. Intelligent systems are the only viable techniques capable of bringing real-time analysis and decision-making power to the new hardware.

An integrated, intelligent software tool must have several important attributes, such as the ability to integrate hard (statistical) and soft (intelligent) computing and to integrate several AI techniques. The most used techniques in the Oil and Gas sector are:

  • Genetic Algorithm (GA), inspired by the biological evolution of species in natural environment, consists of a stochastic algorithm in which three key parameters must be defined:
    1. Chromosomes, or better, vectors constituted by a fixed number of parameters (genes).
    2. A collection of chromosomes called genotype, which represents the individuals of a population.
    3. The operations of selection, mutation, and crossover to produce a population from one generation (parents) to the next (offspring).
  • Fuzzy Logic (FL) is a mathematical tool able to covert crisp (discrete) information as input and to predict the correspondent crisp outlet by means of a knowledge base (database) and a specific reasoning mechanism. To achieve such goal, the crisp information is firstly converted into a continuous (fuzzy) form, secondly processed by an inference engine and at least re-converted to a crisp form.
  • Artificial neural network (ANN) is constituted by a large number simple processing units, characterized by a state of activation, which communicate between them by sending signals of different weight. The overall interaction of the units produces, together with an external input, a processed output. The latter is also responsible of changing the state of activation of the units themselves.

The techniques described above have been adopted in the Oil and Gas field since 1989. Relatively to O&G industry, Figure 1 shows the number of applications of AI.


fig 1_

Figure 1 Artificial intelligence (AI) applications in the Oil and Gas industry during the years.


In the following sections some of the application of AI in the O&G sector will be analyzed with a particular focus on the Drilling operation (Exploration & Production).

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Petroleum Technologies and Sustainability in the Era of Climate Change

Authors: Marco Cocchi – Researcher – Campus Bio-medico University of Rome
                Leone Mazzeo – Researcher – Campus Bio-medico University of  Rome


1          Introduction

The climate change is the biggest challenge that the human kind have ever had to deal with. Despite a residual skepticism on the topic, “climate change is real”[1] and it is already influencing and it will influence the life on Earth.

The cause of climate change is attributed to the significant increase of greenhouse gases (mainly CO2) in the atmosphere, able to trap heat radiating from Earth toward space. By means of the analysis of ice cores[2] it has been discovered that, for millennia, the concentration of carbon dioxide in atmosphere has been below 300 ppm. As it is shown in the Figure 1, such threshold was broken in 1950 and, since then, the concentration of CO2 has never stop growing reaching in 2019 the value of 410 ppm[3].

CO2 capture

Figure 1 Variation of carbon dioxide concentration during millennia estimated from atmospheric samples collected from ice cores3.

According on the considerations mentioned above, the 21st century is indeed recognized as the “era of climate change” mainly characterized by the increase of the land-ocean mean surface temperature (GMST) and, as a consequence, by other environmental phenomena such as the increase of the average sea level and the retreat of glaciers.

The reason why the amount of GHGs in the atmosphere is increasing so rapidly is strictly connected to the growth of the world population driven by the development of the industrial sector. Since the mid-20th century the anthropogenic CO2 emissions have raised exponentially (see Figure 2) in line with the trend detected of the carbon dioxide concentration in atmosphere. On top of this, the human action is identified as the main cause of the global warming.


lobal anthropogenic CO2 emissions

Figure 2 Global anthropogenic CO2 emissions[4].


The sign of the Paris Agreement (Paris climate conference – COP21, December 2015), the first-ever universal, legally binding global climate change agreement, represents an important act to the fight against the climate changes. Major players of the Oil & Gas and Energy sector are financing the development of sustainable technologies in order to diminish their significant carbon footprint. The actions of mitigation of the emissions of carbon dioxide are mainly directed to the main sources of CO2 which, as shown in the Figure 3, comes from the combustion of coal, oil and gas, and from the operations of flaring and cement production[5].

 CO2 emissions by fuel type

Figure 3 CO2 emissions by fuel type, [5].



[1] https://sites.nationalacademies.org/cs/groups/internationalsite/documents/webpage/international_080877.pdf
[2] To find more: https://icecores.org/about-ice-cores
[3] https://climate.nasa.gov/
[4] “Climate Change 2014 Synthesis Report Summary Chapter for Policymakers,” 2014.
[5] https://ourworldindata.org/co2-and-other-greenhouse-gas-emissions


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Emergency Sea Protection: New Technologies During Oil Spill

Authors: Marco Cocchi – Researcher – Campus Bio-medico University of Rome
                Leone Mazzeo – Researcher – Campus Bio-medico University of Rome


1          Introduction


Every day, hundreds, if not thousands, of oil spills are likely to occur worldwide in many different types of environments, on land, at sea, and in inland freshwater systems.

The spills are coming from the various parts of the oil industry, mainly during:

  • Oil exploration and production activities.
  • Oil transportation in tank ships, pipelines, and railroad tank cars.

The sea environment is particularly subjected to oil pollution. It is estimated that approximately 706 million gallons of waste oil enter the ocean every year[1]. According to the data of oil spills in the United States published by the Environmental Research Consulting (ERC), large spills (over 30 tons), which the 0,1% are incidents, represent the 60% of the total amount of oil spilled. Despite the latter information, 72% of spills are of smaller amount (0.003 to 0.03 ton or less) as shown in (Figure 1‑1).

 Oil exploration and production activities.

Figure 11 Size classes of U.S. marine oil spills, 1990 e 1999 (ERC data) [2].


Naturally, the relatively rare large spill incidents get the most public attention owing to their greater impact and visibility, for this reason it is impossible to measure the entity of damage only considering the size of spillage. Location and oil type are extremely important. Significant efforts have been made to study oil spills after the Exxon Valdez spillage of 1989 (Figure 1‑3). However, such knowledge has not kept pace with the growth of oil and gas development[3]. In 2010, in the Gulf of Mexico, took place the Deepwater Horizon oil spill (Figure 1‑3) considered one of the most catastrophic environmental disasters in human history. In such occasion, over 4.9 million barrels of crude oil were released involving 180,000 km2 of ocean[4].

Timely and highly efficient responses can lead to more hopeful outcomes with less overall damage to the environment. The most used clean response devices and techniques[5] are (Figure 1‑2):

  • Manual recovery, mainly used for costal oil cleanup, involves a team of workers/volunteers using tools like rakes and shovels to collect the oil into buckets and drums for transfer it to a processing station.
  • Booms, mechanical barriers that protect natural resources from spreading crude oil. They are very useful to confine the oil spill facilitating the cleaning operations.
  • Skimmers, mechanical devices designed to remove oil from the water surface without causing changes to its physical or chemical properties and transfer it to storage tanks. Skimmers are usually used together with booms.
  • Sorbents, materials that can soak up oil from the water by either absorption or adsorption.
  • In situ burning. It is a cleaning technique which consists in a controlled burning of the oil that takes place at, or near, the spill site.
  • Dispersants are chemical spill treating agents, similar to emulsifiers, that accelerate the breakdown of oil into small droplets that “disperse” throughout the water. Dispersants are used to reduce the impact to the shoreline and to promote biodegradation of oil.
  • Bioremediation. It consists of the introduction of a microbial population (bio-augmentation) together with nutrients (bio-stimulation), to enhance the rate of oil biological degradation.

etection and monitoring of oil spillage

Figure 12 A visual overview of all the oil spill response techniques[6].

The detection and monitoring of oil spillage are of fundamental importance to perform a rapid response. Innovations on sea protection involve, in fact, both oil spill monitoring and response techniques.

detection and monitoring of oil spillage

Figure 13 BP Deepwater Horizon blowout 2010 (left), Exxon Valdez spillage (right)[7][8].


[1] http://www.waterencyclopedia.com/Oc-Po/Oil-Spills-Impact-on-the-Ocean.html
[2] D. Schmidt-etkin, Spill Occurrences: A World Overview. D.S. Etkin, 2011.
[3] Li, P., Cai, Q., Lin, W., Chen, B., & Zhang, B. (2016). Offshore oil spill response practices and emerging challenges. Marine Pollution Bulletin, 110, 6–27.
[4] Griggs, J. W. (2011). BP Gulf of Mexico oil spill. Energy Law Journal, 32, 57.
[5] B. Chen, X. Ye, B. Zhang, L. Jing, and K. Lee, Marine Oil Spills — Preparedness and Countermeasures, Second Edition. Elsevier Ltd., 2019.
[6] F. Mapelli et al., “Biotechnologies for Marine Oil Spill Cleanup: Indissoluble Ties with Microorganisms,” Trends Biotechnol., vol. xx, pp. 1–11, 2017.
[7] https://www.hakaimagazine.com/news/wounded-wilderness-the-exxon-valdez-oil-spill-30-years-later/
[8] https://it.wikipedia.org/wiki/Disastro_ambientale_della_piattaforma_petrolifera_Deepwater_Horizon


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Hydrogen Role on the Decarbonization Transition Route

Author: Elvirosa Brancaccio – Serintel Srl – Rome (Italy)



1.     Introduction

Awareness of climate change impacts and the need for deep decarbonization has increased greatly in recent years. In 2018 the EU published its vision for the future of energy in Europe ‘A Clean Planet for All’   which aims at creating a “prosperous, modern, competitive and climate neutral economy by 2050.”  A set of pathways has been developed and assessed that rely heavily on renewable energy and energy efficiency, with a role for natural gas and hydrogen.

The need to accelerate clean energy transitions is underscored by recent data: CO2 emissions rose for a second year in a row in 2018 to reach a record high.



Figure 1 Annual change in global energy-related CO2 emissions, 2014-2018[1]


In response to this growing awareness and the urgency of decarbonization, policy makers have taken action and in 2015 agreed to what is known as the Paris agreement.  This has set the target to limit the expected global average temperature increase to significantly less than 2°C, with the ambition to keep to the limit to less than 1.5°C. In order to achieve such necessary and ambitious targets, the European economy, and in particular the energy sector, needs to significantly reduce CO2 emissions to a fraction of current levels (e.g. -80%, -95%) with a growing consensus that net zero emissions will be required.  Many changes will be required in how we work, travel, heat our homes and how we obtain the energy necessary to carry out all these activities, as shown in Figure 2.


Figure 2 The scale of Europe’s decarbonisation challenge – emissions by sector (MtCO2e)[2]


Hydrogen can help overcome many difficult energy challenges:

  • Integrate more renewables, including by enhancing storage options & tapping their full potential
  • Decarbonize hard-to-abate sectors – steel, chemicals, trucks, ships & planes
  • Enhance energy security by diversifying the fuel mix & providing flexibility to balance grids

Either if there are challenges:

  • costs need to fall;
  • infrastructure needs to be developed;
  • cleaner hydrogen is needed;
  • regulatory barriers persist.[3]

A key feature of hydrogen is its ability to act as both a source of clean energy (for a variety of uses), and an energy carrier for storage. Hydrogen can be transported through existing pipelines, mixed with natural gas, and through dedicated pipelines in the future. It offers an energy storage solution that costs ten times less than batteries.

Hydrogen is already widely used for industrial purposes across the steel, petrochemical and food sectors, but it is now also being used in mobility. In the future, it could also replace natural gas to heat residential and commercial buildings. Hydrogen can also be transformed into clean electricity by injecting it into fuel cells.

The most interesting thing about hydrogen, is that it does not generate carbon dioxide emissions or other climate-changing gases, nor does it produce emissions that are harmful for humans and the environment. For this reason, it will play a key role in ensuring that European and global decarbonisation objectives are achieved by 2050.[4]

Low-carbon hydrogen from fossil fuels is produced at commercial scale today, with more plants planned. It is an opportunity to reduce emissions from refining and industry.


CO2 capture

  Figure 3 Hydrogen production with COcapture is coming online[5].



[1] IEA 2019
[2] Source: 2016 National Inventory Submissions (Common Reporting Format) for EU, Norway and Switzerland Note: Transport here refers to ground-based transport.  Aviation and waterborne transport are counted towards the ‘Other’ segment
[3] IEA, 2019
[4] https://www.snam.it/en/hydrogen_challenge/hydrogen_energy_transition/
[5] Keith Scott, Chapter 1: Introduction to Electrolysis, Electrolysers and Hydrogen Production, in Electrochemical Methods for Hydrogen Production, 2019, pp. 1-27 DOI: 10.1039/9781788016049-00001 eISBN: 978-1-78801-604-9

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