Creating a New Standard In LH2-Refueling Operations
It’s a fact of life in industrial processing that in order to accomplish “good” things you must sometimes have to work with potentially “bad” things. Such is the case with liquid hydrogen, or LH2. For example, as the industrial world continues to look for new ways to move away from the use of traditional fossil fuels to power vehicles and industrial processes, a number of alternatives have begun to rise to the fore. For the most part, this quest to expand the energy pool via “green” clean-energy alternatives is being driven by Environmental, Social and Governance (ESG) initiatives that are aimed at reducing the high carbon footprint, greenhouse gas emissions and ozone depletion potential that are implicit in fossil-fuel usage, which many argue are at the forefront of global climate change.
While propane and liquid natural gas have traditionally been the most popular amongst the new wave of clean-energy fuels – with Europe, China and India at the forefront of their use – hydrogen has begun to gain additional attention and traction as another promising alternative. In fact, in 2021 the U.S. Department of Energy announced the creation of the Regional Clean Hydrogen Hubs program, which offered $7 billion in grants to companies that would like to develop more hydrogen liquefaction plants, with many traditional oil-and-gas producers showing interest in expanding their horizons into the LH2 universe. In late 2023, seven hub-projects were selected for funding through the program, with a network of new liquefaction facilities that will eventually span the country from the Mid-Atlantic to Pacific Northwest and Gulf Coast to Upper Midwest. Additionally, besides all the controversies around the electric vehicle (EV) market and applications, electrification alone can’t solve the road to zero emissions given its interconnectivity with the grid and battery-technology limitations.
The simple truth is that a clean-energy future is coming, but it can only be realized once an infrastructure is in place that makes the use of alternative fuels economically viable – and unquestionably safe to dispense. This white paper will focus on the challenges that are inherent in the dispensing of LH2 and how they must be overcome before the fuel can assume a prominent place in the world’s motor-fuel pool. To that end, enterprising companies are looking for ways to optimize the dispensing of LH2 in terms of efficiency, reliability and – most importantly – safety through the development of innovative dispensing technologies, all while attempting to make the refueling process for the consumer as similar and familiar to that of the traditional service station as possible.
The Challenge
While LH2 can theoretically be used to power all motor vehicles, its capabilities are beginning to make it a top choice as a reliable and efficient fuel for use in long-haul vehicles such as transport trucks, planes and ships. However, getting the fuel from Point A to Point B in the massive amounts in which it is needed can be problematic.
So, while LH2 possesses great potential for growth in its use as an energy source, buoyed by its carbon-neutral status and environmentally sensitive emissions of water and air as it is consumed, the volatile nature of LH2 can make it challenging to harvest, refine, transport, dispense and consume. This makes ensuring safety for the handler and environment Job No. 1 along its production and supply chain, no matter the amount handled or dispensed.
Most notably, LH2 possesses a working temperature of -423ºF (-253ºC) that is close to absolute zero, or -460ºF (-273ºC), making LH2 one of the most challenging cryogenic gases. This means that the equipment that is used to dispense LH2 must contain massive amounts of thermal insulation in the dispensing nozzle so that huge ambient losses in volume will not occur due to evaporation as the fuel is being dispensed.
Another phenomena that developers of LH2 nozzles must be cognizant of is preventing the occurrence of hydrogen embrittlement. It’s a physical fact that all metals will be detrimentally affected at some level by hydrogen, with the level of exposure helping to determine if any embrittlement will occur. If a metal does experience hydrogen embrittlement, it can result in noteworthy losses in tensile strength, ductility and fracture toughness along with accelerated fatigue-crack growth. When the level of embrittlement reaches a critical point, the result can be catastrophic failure of LH2-containing components.
To lessen the risk that hydrogen embrittlement will take place in an LH2-dispensing nozzle, metals that are more resistant to hydrogen embrittlement should be used, such as high-quality stainless-steel grades. Sealing on moving parts is another area where precision in material selection and engineering must be optimized in order to ensure a safe refueling solution.
With this in mind, note that many common elastomers are not suitable for use with cryogenic substances. In this case, the recommended seal type is one constructed from polychlorotrifluoroethylene, or PCTFE. PCTFE stands out in cryogenic service because of its high tensile strength and good thermal characteristics. This combination of exceptional physical characteristics and stability at ultra-low temperatures make PCTFE an ideal choice for equipment used in LH2 dispensing.
Additionally, the nozzle must be constructed so that there is no chance that leakage will occur and if a leak does happen, the nozzle’s operation must be able to be instantly halted in order to prevent a potentially dangerous scenario from developing. On top of that, the nozzle must possess automated flow-control capabilities that enable the operator to be physically situated at a safe distance as the refueling process takes place.
One final operational concern with LH2 is the potential for the buildup of condensed liquid air on the nozzle during a refueling activity. This condensed liquid air is extremely combustible liquid oxygen. Therefore, the LH2-dispensing system must be jacketed and have an extremely high vacuum in order to keep the outer surfaces at ambient temperature so there can be no buildup of liquid air.
The Solution
RegO® Products, a member of OPW Clean Energy Solutions (OPW CES), is a longtime developer of systems and equipment for use in the handling of clean-energy alternative fuels, such as LH2. Recognizing the challenges that are the hallmark of LH2 handling – along with the need that its safe handling must be ensured in every instance – RegO has developed the HydrOMac® LH2 Refueling Nozzle.
The HydrOMac® nozzle has been designed to be a robust LH2 transfer and dispensing solution that possesses the capability to replicate a safe and reliable traditional diesel-like handling and dispensing experience for the consumer.
The HydrOMac® nozzle offers the following features and benefits:
- Unique design that diminishes complexity in LH2 dispensing
- Built-in leak-detection capability
- Automated fuel control that enables the operator to remain in a remote location during the refueling process
- Three-stage thermal-isolated method of operation that optimizes efficiency and performance
- Jacketing that meets the low-temperature handling requirements of LH2 and resists the dangerous buildup of liquid air
- Lighter weight than competitive models that makes for easier handling
These features and benefits, along with the safety-inducing operational capabilities of the HydrOMac® LH2 Refueling Nozzle make it a very intuitive product to use. The removal of any ambiguity in its handling or operation also allows the sellers of LH2 to create a dispensing process that mimics the “culture” of traditional vehicle fueling, which can help ease any concerns the consumer may have when dispensing an unfamiliar fuel.
The HydrOMac® LH2 Refueling Nozzle is the latest addition to the RegO product portfolio of hydrogen-handling products that includes gate and globe valves, relief valves, regulators, HP master valves, check valves and angle relief valves.
Conclusion
There’s no getting around it – the clean-energy future is coming and in order to optimize its potential from a production, supply, financial and safety aspect it must be outfitted with equipment and systems that are able to meet the unique handling characteristics of the growing roster of clean-energy fuels. In that vein, LH2 stands poised to assume an elevated role in the nation’s motor-fuel pool, especially as it relates to the fueling of large vehicles.
In order to achieve success, though, the world’s producers and suppliers of LH2 must be fully aware of the “bad” characteristics that are fundamental to its handling and dispensing in order to realize the “good” that can come from its use. RegO and OPW Clean Energy Solutions have taken a positive step forward in that quest with the development of the HydrOMac® LH2 Refueling Nozzle, which possesses the ability to be a first-choice technology in an optimized, mainstream and inherently safe LH2-refueling operation.
About The Author:
Felipe Machado is the Senior Director of Commercial, Product and Marketing for Hydrogen and Cryogenics for OPW Clean Energy Solutions and can be reached at felipe.sperdutimachado@opwces.com. OPW Clean Energy Solutions was formed in December 2021 when OPW acquired both ACME Cryogenics and RegO® Products. Since then, the company has continued to expand its reach as a supplier of clean-energy fluid-handling equipment and systems, most notably with the acquisitions in 2024 of Demaco, Marshall Excelsior Company (MEC) and SPS Cryogenics/Special Gas Systems (SPS-SGS). ACME is a leading provider of mission-critical cryogenics products and services that facilitate the production, storage and distribution of cryogenics liquids and gases. RegO is a leading provider of highly engineered flow-control solutions for the cryogenic and liquified-gas end markets. Demaco specializes in the development of vacuum-insulated piping solutions for the cryogenics industry. MEC and its subsidiaries CPC Cryolab, BASE Engineering, Inc., and Xanik develop and supply mission-critical flow-control products and solutions for the LNG and anhydrous ammonia (NH3) markets. SPS-SGS is a manufacturer of vacuum-insulated pipeline systems for use in the handling of a wide array of industrial gases. Together, they are taking OPW beyond conventional fueling solutions and helping define what’s next for alternative energy markets. For more information on OPW Clean Energy Solutions, please visit opwces.com.