Pumps for the Hydrogen Economy (H₂)

The Colors of Hydrogen

Hydrogen as an element is colorless. However, different colors are assigned to H2 depending on its origin. An overview of the most important colors:

• Green Hydrogen is produced from renewable energy, in particular by electrolyzing water using electricity from renewable sources such as wind or solar energy.
• Grey Hydrogen is produced by reforming fossil fuels, in particular natural gas. This process produces CO2 as a by-product.
• Blue Hydrogen is essentially gray hydrogen, in which CO2 emissions are captured and reduced through the use of CCS technologies (CCS = Carbon Capture and Storage).
• Turquoise Hydrogen is hydrogen produced by the thermal decomposition of methane (methane pyrolysis).

In addition to these colors, there are others that are used less frequently. Pink or yellow hydrogen, for example, is hydrogen that is also produced by electrolysis – although in this case the electricity required comes from nuclear energy. Although this does not produce CO2, it does produce radioactive waste.

Renewable Energies: The Key to green Hydrogen

Green power generation is an indispensable foundation of the sustainable economy of the future. “Green” means that energy is generated from renewable sources, i.e. without fossil fuels and (almost) without carbon dioxide emissions. Green energy sources primarily include wind and sun. However, there are other options for sustainable energy generation, such as hydroelectric power plants or biogas production based on biogenic residues.

Pumps play an important role in the generation of wind energy, particularly in connection with a special type of energy storage, pumped storage power plants or pumped storage facilities. Although they are not used directly in wind turbines, these pumps are an integral part of the overall system for storing and supplying wind energy. At times when electricity demand is low and the wind turbines generate more energy than is needed, the excess energy is used to pump water from a lower reservoir to an upper reservoir. This process requires pumping. If the demand for electricity increases and the wind turbines do not generate enough energy, the stored energy can be released from the upper reservoir.

Pumps are also used in solar energy, particularly in connection with solar thermal power plants and solar heating systems. In solar thermal power plants, which use solar collectors or solar mirrors to collect solar radiation and convert it into heat, pumps are required for the fluid circuit and for cooling, for example. Pumps are also indispensable for solar heating systems, for cooling photovoltaic cells and for solar systems with heat exchangers.

It almost goes without saying that hydropower plants cannot function without pumps. Pumped storage power plants require pumps in pumping mode: At times when electricity demand is low and surplus electrical energy is available, electrical energy is used to pump water from the lower reservoir to the upper reservoir. This increases the potential energy of the water and stores the energy for later use. Even in hydropower plants that do not function as pumped storage power plants, pumps are used to supply or regulate water within the plant itself.

Pumps even play an important role in biogas plants: for example in substrate transport, as the organic materials used for biogas production have to be transported to the fermentation tanks or fermenters. Pumps are also used for stirring and mixing in the fermentation tanks, for dosing additives or for dewatering and separation.

The pumps used here already make a contribution to H2 production upstream. The more green electricity that can be used to produce hydrogen, the greener and more environmentally friendly the final hydrogen product.

Efficient Pump Technology for Hydrogen Production

The production of H2 is at the heart of the hydrogen economy. Pumps play an important role in hydrogen production as they help to make the various processes efficient and reliable. Hydrogen production can take place in various ways and pumps are used in different phases of this process.

• Water Supply: In electrolyzers, ultrapure water is split into hydrogen and oxygen. Pumps are used to feed water to the electrolysis cells, where it is then split into hydrogen and oxygen using electrical energy. Pumps which, due to their nature, release few to no ions into the ultrapure water are advantageous here and increase the service life of the electrolyser.
• Liquid Circulation: An aqueous electrolyte solution is often used in electrolysis. Pumps are required to circulate this solution efficiently through the electrolysis cells so that the electrolysis process can run continuously. The pumps used here are therefore often referred to as electrolyte pumps in accordance with their intended use.
• Hydrogen Separation: After electrolysis, the hydrogen produced must be separated from oxygen and other gases. Pumps can also be used here to separate the gases and remove the pure hydrogen. However, depending on the system concept, this can also be done without the use of additional pumps in a separator tank to separate the hydrogen from the water/alkali.
• Hydrogen Compression: The hydrogen produced often has low pressures and must be compressed in order to be stored or transported efficiently. So-called compression pumps (compressors) are used to compress the hydrogen under high pressure and thus liquefy it so that it can then be transported further.
• Hydrogen Storage: When storing hydrogen in tanks or as metal hydride storage tanks, pumps are used to fill and empty the storage tanks.
• Hydrogen Transportation: Pumps are also required for the transportation of hydrogen in pipelines or tank vehicles in order to convey the hydrogen through the pipelines or into the tank vehicles. To improve transportation, another carrier medium such as ammonia or ethanol can be temporarily added here.

The selection of suitable pumps depends on various factors, such as the hydrogen production process, the required pressure and flow rates or the safety requirements. Efficient pumps are crucial to make hydrogen production economical and sustainable, especially when hydrogen is produced from renewable energy sources, as efficiency plays an important role in this case.

Hydrogen Storage for flexible Use of the Energy Source

One of the great advantages of hydrogen as an energy carrier is that H2 can be stored relatively easily – unlike electrical energy, for which often only expensive and resource-intensive battery storage is an option. Pumps play an important role in hydrogen storage, especially in the storage of compressed H₂. Pumps perform the following functions in hydrogen storage:

• Hydrogen Compression: Hydrogen is most efficiently stored in compressed form to increase its storage and transportation efficiency. Compression pumps are used to compress the hydrogen from lower pressures to higher pressures before it is stored or transported in tanks or pipelines. The pumps therefore play a crucial role in efficiently reducing the volume of hydrogen.
• Refueling: During hydrogen refueling of vehicles or stationary hydrogen tanks, pumps are used to transfer the compressed H2 from the storage infrastructure to the tanks. These pumps enable the vehicles or systems to refuel hydrogen quickly and safely.
• Hydrogen Transportation: When hydrogen is transported via pipelines or tanker trucks, pumps are necessary to deliver H2 through the pipelines or into the vehicles. These pumps are important for transporting hydrogen efficiently and safely over long distances.
• Hydrogen Bundling: Hydrogen can be produced decentrally by electrolysis and then stored and distributed in hydrogen tanks. Pumps are used to deliver hydrogen produced in this way into the tanks and to extract it when required.

As with the production of H₂, efficient pumps are also crucial for hydrogen storage in order to make the processes economical and practicable. The development of efficient pumps for these purposes and the continuous improvement of pump technologies are important aspects in promoting the hydrogen economy and the integration of hydrogen into the sustainable energy economy.

Hydrogen Distribution: green Energy for all Consumers

For a successful, efficient hydrogen economy, not only production but also the infrastructure for distribution is crucial. Pumps play a key role here, as they help to transport H2 efficiently from the production site to the consumers. The distribution of hydrogen is a crucial aspect of the hydrogen economy, as H2 (unlike natural gas) cannot usually be distributed in pipelines.

Specifically, pumps in the hydrogen economy of the future will perform the following functions, among others:

• Refueling of Hydrogen Vehicles: Pumps are used in hydrogen refueling stations to pump the compressed H2 from the storage infrastructure into the tanks of hydrogen vehicles. These pumps enable vehicles to refuel with hydrogen quickly and safely.
• Hydrogen Distribution by Truck: Hydrogen can be transported by tank truck or container to hydrogen refueling stations or industrial consumption points. Pumps in these vehicles make it possible to extract the hydrogen from the tanks and pump it into the storage tanks at the points of consumption.
• Hydrogen Pipelines: Even if they are not yet widespread, there will also be pipelines for transporting H2 in the future, for example to industrial plants or other large-scale consumers. Pumps can be used in these pipelines to transport the hydrogen through the pipeline system.
• Hydrogen Storage and Distribution in Plants: In industrial plants that use hydrogen, pumps are used to transfer the hydrogen from the storage tanks to the production facilities. This enables the efficient use of hydrogen in various industrial processes.

The right industrial Pump for your Hydrogen Application

The use of efficient and reliable industrial pumps in all areas of the hydrogen value chain is important to ensure a stable and effective production process, safe storage and reliable distribution. Efficient pumps offer high operational safety and other advantages, such as low wear and easy maintenance, as well as low power consumption and thus additional benefits for the environment and resources.

Choosing the right pump therefore not only fulfills the basic application requirements, but can also offer operators numerous other benefits during their use, which are reflected not least in significantly lower operating and production costs.

The numerous members of the Star Pump Alliance offer a large portfolio of industrial pumps of various types, which are also used in all areas of the hydrogen economy. Simply make a non-binding enquiry for your application. The pump experts at Star Pump Alliance will be happy to select the right pump for you, including the member company that manufactures it. After a detailed check, you will receive an attractive offer.

Alternatively, you can use the free PUMPselector to identify suitable pumps yourself and request a non-binding quote directly from the relevant Star Pump Alliance manufacturers.

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