Hydrogen by technology


Hydrogen can be produced using 4 broad process groups. Within each group, multiple forms of technology have been developed. For the map, we have divided the dataset into these groups. The database and map are intended to be evergreen. As the hydrogen sector develops, the PE Media Network data and maps team will be adding more projects. Most of the current projects indicated on the map fall into the Thermal and Electrolytic process groups.

Thermal processes for hydrogen production typically involve steam reforming, a high-temperature process in which steam reacts with a hydrocarbon fuel to produce hydrogen. Many hydrocarbon fuels can be reformed to produce hydrogen, including natural gas, diesel, renewable liquid fuels, gasified coal, or gasified biomass. Today, about 95% of all hydrogen is produced from steam reforming from natural gas.

Water can be separated into oxygen and hydrogen through a process called electrolysis. Electrolytic processes take place in an electrolyser, which functions much like a fuel cell in reverse. Instead of using the energy of a hydrogen molecule, like a fuel cell, an electrolyser creates hydrogen from water molecules.

Biological processes use microbes, such as bacteria and microalgae, to produce hydrogen. In microbial biomass conversion, the microbes break down organic matter like biomass or wastewater to produce hydrogen, while in photobiological processes the microbes use sunlight as their energy source.

Solar-driven processes use light as the agent for hydrogen production. Solar-driven processes include photobiology, photoelectrochemical reactions and solar thermochemical reactions. Photobiological processes use the natural photosynthetic activity of bacteria and green algae to produce hydrogen. Photoelectrochemical processes use specialised semiconductors to separate water into hydrogen and oxygen. Solar thermochemical hydrogen production uses concentrated solar power to drive water splitting reactions, often along with other species such as metal oxides.

Field Description
Project Project Name
Technology group The group into which the technology type falls into
Technology Technology type or process
Scope Description of the project
Product Principle product produced. Usually, hydrogen (H2) or methane (CH4)
H2 Power Supply of electricity to the electricity grid with a gas turbine of fuel cell
H2 Grid Injection Injection in natural gas or pure hydrogen grids
H2 Mobility Used vehicles (road, off-road, rail, maritime or aviation)
H2 Industry Industrial applications such as refineries, steel plants or high temperature heat
H2 CHP Heat and power via CHPs, for example in fuel cells or turbines
H2 Domestic Heat Direct use in building for water and space heating
H2 Chemicals Production of (intermediate) chemicals, such as methanol, ammonia (for fertiliser or chemical products) or final chemical products.
CH4 Grid Injection Grid injection as end user sector
CH4 Mobility Used vehicles (road, off-road, rail, maritime or aviation)
Synfuels Mobility Used vehicles (road, off-road, rail, maritime or aviation)
Status Phase of project
Sub-status Additional stage of the project
Announced start date Date at which the project will start
Operator The project operator or promotor
Abbreviations Description
ALK Alkaline Electrolyser
ATR Autothermal Reforming
CCGT Combine-Cycle Gas Turbine
CCS Carbon Capture & Storage
CCUS Carbon Capture, Utilisation & Storage
DAC Direct Air Capture
HEE Hygenic Earth Energy
HTSE High Temperature Steam Electrolysis [Nuclear]
LTE Low Temperature Electrolysis
NG Natural Gas
PEM Polymer Electrolyte Membrane Electrolysis
PtX Power to X
SMR Steam Methane Reforming
SOEC Solid Oxide Electrolyser Cell
SPEG Solena Plasma Enhanced Gasification [Recycled Waste]

H2 Technology graphs

Based upon data from the map above

Total number of projects by technology type

Excluding unknowns

Data shown illustrates total number of projects with a known technology type or process

Total number of projects

By region

Data shown illustrates total number of projects from the above graphic split by region

Total number of projects

By country

Data shown illustrates total number of projects from the above graphic split by country

Technology types

Low temperature electrolysis (LTE)


Low-temperature electrolysis (e.g., see Alkaline or Polymer electrolyte membrane water electrolysis) enables high-performance and compact hydrogen production that can be combined with energy storage and transport systems.

High temperature steam electrolysis (HTSE)


High-temperature steam electrolysis is a technology for producing hydrogen from water at high temperatures. The process utilises thermal energy released from the nuclear reactors.

Carbon capture & Storage (CCS)

Carbon capture and storage (CCS) is the process of capturing and storing carbon dioxide before it is released into the atmosphere. The technology can capture 90% or more of carbon dioxide released by burning fossil fuels in electricity generation and industrial processes such as cement production.

Carbon capture, Utilisation & Storage (CCUS)

Carbon capture, utilisation, and storage (CCUS), also referred to as carbon capture, utilisation and sequestration, is a process that captures carbon dioxide emissions from sources like coal-fired power plants and either reuses or stores it so it will not enter the atmosphere.

Polymer electrolyte membrane electrolysis (PEM)


Polymer electrolyte membrane (PEM) is the electrolysis of water in a cell equipped with a solid polymer electrolyte (SPE) that is responsible for the conduction of protons, separation of product gases and electrical insulation of the electrodes. The PEM electrolyser was introduced to overcome the issues of partial load, low current density and low-pressure operation currently plaguing the alkaline electrolyser.

Solid oxide electrolyser cell (SOEC)


A solid oxide electrolyser cell (SOEC) is a solid oxide fuel cell that runs in regenerative mode to achieve the electrolysis of water (and/or carbon dioxide) by using a solid oxide, or ceramic, electrolyte to produce hydrogen gas (and/or carbon monoxide) and oxygen.

Autothermal reforming (ATR)


Autothermal reforming is a process for producing syngas, composed of hydrogen and carbon monoxide, by partially oxidising a hydrocarbon feed with oxygen and steam and subsequent catalytic reforming. Depending on customers' needs (mainly syngas composition or plant capacity), Air Liquide Engineering & Construction can provide ATR as a stand-alone technology or in conjunction with Steam Methane Reforming, a technology known as Combined Reforming.

Alkalkine electrolyser (ALK)


Description: Alkaline water electrolysis is a type of electrolyser that is characterised by having two electrodes operating in a liquid alkaline electrolyte solution of potassium hydroxide (KOH) or sodium hydroxide (NaOH). These electrodes are separated by a diaphragm, which divides the product gases including hydrogen and transports the hydroxide ions (OH−) from one electrode to the other. Example types: Augmented McLyzer (ALK)

Direct air capture (DAC)


Direct Air Capture (DAC) is a technology that pulls in atmospheric air, then through a series of chemical reactions extracts the carbon dioxide from it while returning the rest of the air to the environment. This is what plants and trees do every day as they photosynthesise, only that Direct Air Capture technology does it much faster, with a smaller land footprint, and delivers the carbon dioxide in a pure, compressed form that can then be stored underground or reused.



Gasification is a process that converts biomass or fossil fuel-based carbonaceous materials into gases, including the following: nitrogen, carbon monoxide, hydrogen and carbon dioxide. By reacting the feedstock material at high temperatures (typically >700 °C) without combustion, via controlling the amount of oxygen and/or steam present in the reaction, the resulting gas mixture is called syngas (from synthesis gas) or producer gas. It is itself classed as a fuel, due to the flammability of the H2 and CO of which the gas is largely composed. Power can be derived from the subsequent combustion of the resultant gas and is a source of renewable energy if the compounds were obtained from biomass feedstock. Example types: Biomass gasification, Bitumen gasification, Coal gasification, Petroleum coke gasification, Plasma gasification

Steam methane reforming (SMR)


Steam reforming or steam methane reforming is a method for producing syngas (hydrogen and carbon monoxide) by reaction of hydrocarbons with water. Commonly, natural gas is the feedstock. The main purpose of this technology is hydrogen production, and the chemical reaction is CH4 + H2O ⇌ CO + 3 H2 Hydrogen produced by steam reforming can be termed 'grey hydrogen' when the waste carbon dioxide (CO2) is released to the atmosphere and 'blue hydrogen' when the carbon dioxide is (mostly) captured and stored geologically - see Carbon capture & storage, Carbon capture, utilisation & storage
Steam reforming of natural gas produces most of the world's hydrogen.

Power to X (PtX)


Power-to-X is several electricity conversions, energy storage and reconversion pathways that use surplus electric power, typically during periods where fluctuating renewable energy generation exceeds load. Power-to-X conversion technologies allow for the decoupling of power from the electricity sector for use in other sectors (such as transport or chemicals), possibly using power that has been provided by additional investments in generation. The X in the terminology can refer to one of the following: power-to-ammonia, power-to-chemicals, power-to-fuel, power-to-gas, power-to-hydrogen, power-to-liquid, power-to-methane, power-to-food, power-to-power, and power-to-syngas. Much of the database refers to unknown PtX.