Ohmium, an American hydrogen energy startup founded in 2019, designs, manufactures, and deploys advanced Proton Exchange Membrane (PEM) electrolyzer systems. These systems are used to produce green hydrogen on-site by splitting water into hydrogen and oxygen using renewable electrical current, a process that is considered environmentally friendly when powered by renewable energy sources. Ohmium’s on-site hydrogen production is aimed at helping customers achieve their sustainable energy goals across industrial, transportation, and energy projects.
Challenges: green hydrogen
The Pivotal Role of Hydrogen in a Sustainable Future
Hydrogen (H₂), the most abundant element in the universe, is not just a fundamental building block of stars—it’s also a vital ingredient in the synthesis of ammonia. Ammonia production is at the heart of creating a plethora of products that we rely on daily, from the fertilizers that nourish our crops to the plastics that are woven into the fabric of modern life.
Traditionally, the world has leaned heavily on steam methane reforming (SMR) to produce over 60 million tons of hydrogen annually. However, this method comes with a significant environmental cost. It’s an energy-intensive process that contributes approximately 2% to the global carbon dioxide (CO₂) emissions, releasing between 5 and 9 tons of CO₂ for every ton of hydrogen it generates.
But there’s a cleaner path forward: water electrolysis. This process splits water into hydrogen and oxygen using electric current and comes in various forms, including alkaline water electrolyzer (AWE), proton exchange membrane water electrolyzer (PEMWE), and solid oxide electrolysis cells (SOEC). When these electrolyzers are powered by renewable energy sources—think nuclear, solar, and wind power—the result is “green hydrogen.”
Green hydrogen is more than just an eco-friendly alternative; it’s a beacon of hope for decarbonizing sectors that have traditionally been challenging to reform. Industries like steel manufacturing, long-distance transportation, and even aviation and shipping, which have long been tethered to fossil fuels, can now envision a greener horizon.
In our quest for a carbon-neutral world, green hydrogen isn’t just an option—it’s an imperative. As we harness the power of renewables to produce this clean energy carrier, we’re paving the way for a sustainable future, one where the sky is no longer the limit, but the starting point for innovation and environmental stewardship.
PEM electrolyzer
Proton Exchange Membrane (PEM) electrolyzers are one of key technologies for hydrogen production, offering a clean and efficient method to generate hydrogen from water using electricity. This technology is particularly appealing for integrating with renewable energy sources to produce green hydrogen, contributing to the decarbonization of various sectors including transportation, industry, and energy storage.
PEM electrolyzers utilize a solid polymer electrolyte (SPE) to conduct protons from the anode to the cathode while insulating the electrodes electrically. At the anode, water is oxidized to produce oxygen, protons, and electrons. The protons are conducted through the membrane to the cathode, where they combine with electrons to produce hydrogen gas. This process is driven by an external power source, typically from renewable energy sources to ensure the hydrogen produced is green.
Ohmium Technology
Ohmium has developed an advanced PEM electrolyzer system that produces pure hydrogen on-site for industrial applications. By recycling the exhaust gas of the industrial hydrogen application process, the system has an improved overall efficiency.
Ohmium uses porous titanium gas diffusion layers on the PEM electrolyzer stack’s anodes. This porous titanium gas diffusion layer is fabricated using a powder technique that is protected by a patent, such as powder metallurgy or tape casting.
Ohmium PEM electrolyzer cell structure
The diagram below depicts the structure of Ohmium PEM electrolyzer cell.
The PEM electrolyzer cell includes:
- Flow plates
The anode-side flow plate has a water inlet, a water flow channel (e.g., tortuous path groove), and an oxygen/water outlet. This flow plate faces the anode-side gas diffusion layer.
The cathode-side flow plate has a hydrogen gas flow channel and a hydrogen gas outlet. This flow plate faces the cathode-side gas diffusion layer.
- PEM polymer electrolyte
There is a PEM polymer electrolyte in the middle of the two flow plates. It prevents the gas products from mixing and the electrodes from contacting.
The PEM can be a Nafion® membrane made of a fluoropolymer-copolymer based on sulfonated tetrafluoroethylene.
- Gas diffusion layers
The anode-side gas diffusion layer is composed of a porous titanium. The porous titanium gas diffusion layer contains noble metal to enhance its conductivity. Ohmium has a patent that protects the way they fabricate this porous titanium gas diffusion layer for the PEM electrolyzer. A powder technique, such as tape casting or powder metallurgy, is used to make this layer.
The cathode-side gas diffusion layer is composed of a porous carbon.
- Electrodes
The anode and cathode are sandwiched between their gas diffusion layers and the PEM electrolyte, respectively. The anode is composed of a catalyst layer of iridium, which prompts the oxygen evolution reaction (OER). The cathode is made of a catalyst layer of platinum, which prompts the hydrogen evolution reaction (HER).
The diagram below depicts how Ohmium PEM electrolyzer produces hydrogen.
In operation, water is fed to the anode flow field plate through the water inlet opening. Water in the flow channel flows through the porous titanium gas diffusion layer to the anode.
Upon applying an external voltage between the two electrodes, water is electrochemically split into oxygen gas and protons at the anode electrode, according to the half reaction:
H₂O → 1/2O₂ + 2H⁺ + e⁻
Oxygen gas diffuses back through the porous titanium gas diffusion layer to the anode-side flow field plate. It exits the electrolyzer through the outlet opening.
Hydrogen ions diffuse through the PEM polymer electrolyte to the cathode. They are reduced to hydrogen gas, according to the half reaction:
2H⁺ + 2e⁻ → H₂
Hydrogen gas diffuses through the porous carbon gas diffusion layer. It exits through the flow channel and outlet opening in the cathode-side flow field plate.
Ohmium PEM electrolyzer stack
The diagram below depicts the Ohmium PEM electrolyzer stack.
The electrolyzer stack is composed of a stack of multiple PEM electrolyzer cells. The stack has inlet and outlet openings on the anode-side flow field end plate. Through the inlet opening, water is fed to the anodes of each electrolyzer cell. Oxygen gas is produced at the anode of each cell. They combine into an oxygen gas stream and exit through the outlet opening.
The electrolyzer stack also has an outlet opening on the cathode-side flow field end plate. Hydrogen gas is generated on the cathode of each electrolyzer cell. They combine into a hydrogen gas stream and exit the electrolyzer stack through the outlet opening at 40 ºC. The moisture content of the hydrogen gas stream is about 2 mol%.
Ohmium PEM electrolyzer system
The diagram below depicts the Ohmium PEM electrolyzer system.
The system has a PEM electrolyzer stack as described above. The stack produces hydrogen and oxygen from purified water.
Oxygen and water flow out of the anode of the PEM electrolyzer stack is sent to a separator, which filters out the oxygen. The separated water is sent to a reservoir, which purifies water so that the PEM electrolyzer stack can use it.
The wet hydrogen out of the cathode of the PEM electrolyzer stack is sent to a dryer. The dryer removes water, producing a dry hydrogen stream.
Afterward, the dry hydrogen stream is sent to a purifier. The purifier removes additional water and other impurities, such as oxygen, nitrogen, hydrocarbons, and argon. It sends a stream of pure hydrogen to a process that needs hydrogen, like a metals furnace and a glass float furnace.
The application that uses hydrogen makes exhaust gas. There is a hydrogen pump that can send it back to the cathode output stream of the PEM electrolyzer for reuse. This makes the system work more efficiently as a whole. In the event that oxygen is found in the exhaust gas, it cannot be reused.
The hydrogen pump produces a purge water stream and a wet hydrogen stream. This wet hydrogen stream is then recycled into the system by directing it to the dryer.
Ohmium Patent
- US20220023946A1 Porous electrolyzer gas diffusion layer and method of making thereof
- US20230015026A1 Systems and methods for hydrogen recovery
- S20230228487A1 System and method for drying using hydrogen combustion exhaust
- US20220131165A1 Aircraft electrical power supply system and method of supplying electrical power in an aircraft
- US20230178993A1 Systems and techniques for renewable energy generation
- US20220033984A1 Modular system for hydrogen and ammonia generation without direct water input from central source
- US20230175144A1 Solar driven aquaculture farm with oxygen generation for enhanced population health stability
- US20230315054A1 Assessing, monitoring, and/or controlling hydrogen-production installations
- US11773001B2 Systems and methods of electrochemical hydrogen generation to provide a reducing ambient for industrial fabrication
- US20230279564A1 Hydrophilic member with cation and anion conducting membranes
- US20230175155A1 Water supply oxygenation systems and methods
- US20230313398A1 System and method for controlling operations of electrolyzers based on reactive power
- US20230175148A1 System for photovoltaic energy production and hydrogen generation having a repeatable layout
- US20230174026A1 Solar highway with integrated energy pipeline and vehicle recharging or refueling stations
- US20230231162A1 System and method for controlling hydrogen stack current and load
- US20230175145A1 Photo electrolysis device with photovoltaic driven hydrogen pump for hydrogen generation and water oxygenation
- US20230332315A1 System and method for controlling production, storage, and/or distribution of hydrogen
- US20220404846A1 Multiple output header
- US20230332313A1 Voltage and frequency response and regulation in a hydrogen generation system
- US20230322109A1 Ancillary electric vehicle or fuel cell electric vehicle charging and refueling
- US20230335990A1 Frequency droop to coordinate hydrogen production
- US20230332317A1 Hydrogen generation system with redundant oxygen or hydrogen monitoring
- US20230178991A1 Integrated solar to long term energy storage system with weather sensing
- US20230357941A1 Systems and methods for hydrogen and ammonia production
- US20240072285A1 Energy storing electricity generator
- US20230333530A1 System and method for efficiently generating hydrogen using multiple available power sources
- US20230175706A1 Integrated systems for generating thermal energy and hydrogen
- US20230332311A1 Hydrogen generation system with mission critical control
- US20230332312A1 System and method for controlling hydrogen production based on power production and/or power consumption
- US20230332316A1 Power distribution for a hydrogen generation system
- CL2023001357S1 Electrolyzer cabinet
- WO2024049837A2 Energy storing electricity generator
Ohmium Technology Applications
- Ammonia Production
Ohmium has signed an agreement to provide 343 MW of green hydrogen electrolyzers to Tarafert for a large-scale urea fertilizer and green ammonia production facility in Mexico. The green hydrogen produced by Ohmium’s electrolyzers will enable the production of up to 200,000 metric tons per year of green ammonia, which is a key ingredient in fertilizers.
- Steel and Iron Processing
Ohmium is collaborating with Emirates Steel Arkan and Khalifa University on a research and development program to decarbonize the steel industry. This partnership aims to incorporate Ohmium’s advanced PEM electrolyzers into the steel production process to produce high-value, low-carbon impact steel, aligning with the UAE’s goal to achieve net-zero emissions by 2050.
- Methanol Production
While the search results do not directly mention Ohmium’s involvement in methanol production, PEM electrolyzers like those produced by Ohmium can be used to generate green hydrogen, which is a potential feedstock for producing green methanol. Green methanol is produced by combining green hydrogen with captured carbon dioxide, offering a sustainable alternative to traditional methanol production methods that rely on fossil fuels.
- Petroleum Refining
Ohmium’s PEM electrolyzer technology can be applied in petroleum refining to produce green hydrogen, which can be used in various refining processes such as hydrocracking and desulfurization. Green hydrogen serves as a cleaner alternative to hydrogen produced from natural gas, helping refineries reduce their carbon footprint and comply with stricter environmental regulations.
Ohmium Products
Lotus Mark 1
The Lotus Mark 1 Electrolyzer is capable of producing 6 kg of hydrogen per hour at 400 psi, with a purity greater than 99.99% and less than 5 parts per million of oxygen present in the final product. It requires 480VAC / 415VAC, 60Hz / 50Hz of power and is rated to operate between -13 degrees F to 122 degrees F. Each cabinet measures 6′ x 4′ x 6′ and is designed to UL 2264A standards
Lotus Mark 2
The Lotus Mark 2 Electrolyzer is scalable from megawatts to gigawatts and features an outdoor, interlocking-modular, rack in/out system. This design allows for rapid installation and dynamic operation, adapting to input power and load variations.
The system is capable of producing hydrogen at a rate of 9 kg per hour, with a pressure of 35 bar (507 PSI) and purity up to 99.999%. It operates on 480 VAC / 415 VAC, 60 Hz / 50 Hz, with optional DC integration, and is designed for outdoor environments rated for -25° C to 50° C (-13° F to 122° F). The Lotus Mark 2 product is designed to meet UL 2264A and ISO 22734 standards and is installed per NFPA 2.
Ohmium Funding
Ohmium has raised a total of $295M in funding over 2 rounds:
Their latest funding was raised on Apr 26, 2023 from a Series C round.
Ohmium Investors
Ohmium is funded by 4 investors:
- TPG Rise Climate Fund
- Fenice Investment Group
- Hanover Technology Investment Management
- Energy Transition Ventures
Fenice Investment Group and Hanover Technology Investment Management are the most recent investors.
Ohmium Founder
Arne Ballantine and Kirsten Burpee are Co-Founder.
Ohmium CEO
Arne Ballantine is CEO.