From pv magazine global
A group of scientists from the Oregon Center for Electrochemistry (OCE) and Arizona-based zero-emission vehicle company Nikola has investigated whether electrolyzers and fuel cells powered by intermittent wind and solar may become economically competitive in providing seasonal energy storage in the U.S. energy market. “Our paper investigates multiple end-uses of fuel cells for grid power and shipping,” the research’s corresponding author, Paul Kempler, told pv magazine. “It remains to be seen whether electrolyzers will be able to operate under intermittent availability provided by both wind and solar. The cost of electrolyzers is also certain to fall over the next ten years due to the widespread scale-up of production capacity and intermittently-powered electrolyzers and fuel cells is a new idea here that could be quite important by 2040-2050 in a U.S. grid powered primarily by wind and sunlight.”
In the study “Research priorities for seasonal energy storage using electrolyzers and fuel cells,” published in Joule, Kempler and his colleagues defined long-duration energy storage (LDES) as storage solutions with energy capacities equivalent to over 10 hours of rated power, with optimal levels reaching 100 hours. “The low lifetime number of charge-discharge cycles associated with seasonal storage makes storage capital costs over $10/kWh uncompetitive with existing sources of firm generation,” the paper reads.
They modeled a US energy system relying 100% on wind and solar and supported by 200GW of LDES with a storage capacity of 80,000GWh. “For comparison, electrification of the entire fleet of light-duty vehicles in the US would require 200 times less power capacity but 83 times greater energy storage capacity,” they also explained, noting that hydrogen stored in caverns or pipes may reach costs that may be 10 times below the capital cost of pumped-hydro storage or vanadium redox flow batteries.
The academics reported that hydrogen can currently be produced at over $10/kg and emphasized the need for the hydrogen industry to improve the efficiency and costs of both electrolyzers and fuel cells. According to them, the U.S. Department of Energy (DoE) target hydrogen price of $1/kg may only be achieved through the availability of very low cost electricity, at less than $0.05/kWh. “Low prices for wind and solar in regions such as California and Texas are available today and will become increasingly available over the next decade,” Kempler stated, noting that the bottom range of wind and solar levelized energy costs is now around $0.03/kWh, according to US-based Lazard. “Power purchase agreements have already been signed for $0.02/kWh in California and costs for direct use of wind and solar are likely to continue to decline as the technologies are scaled.”
According to the research group’s calculations, an affordable hydrogen-based system for seasonal energy storage could be achieved at a hydrogen price lower than $3/kg, produced from inexpensive renewable electricity at $0.02/kWh. “For modeled electrolysis stacks available at $200/kW, a hydrogen cost target of $1/kg is met at electricity rates [of] $0.02/kWh by future solid oxide electrolyzer cell (SOEC) electrolyzers operating at 1.2V or at electricity rates [of] $0.01/kWh by future proton exchange membrane (PEM) electrolyzers operating at 1.75V,” it concluded. “Growth of fuel cell markets from applications in back-up power to heavy-duty transportation could be leveraged to satisfy the need for inexpensive, low-capacity-factor power discharge facilities.”
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Hydrogen is a win-win for everyone and is immune to political ideology. Indeed, it has brought Republicans and Democrats together all across the country. So much so that there is now a groundswell of development that can make hydrogen cheap and abundant in just five years. That is a good thing because hydrogen is our only effective means to fight climate change at scale — with energy independence as an added bonus.
Nonetheless, setting up the hydrogen infrastructure remains a challenge. One way to get things moving is to use existing jet engine technology in aviation and use existing engine technology in trucking. This is why Srikanth Padmanabhan thinks that hydrogen-fueled internal combustion engines can help us get there:
“By creating a viable use case and demand for hydrogen in the near term, we can accelerate hydrogen infrastructure build-out and increase scale production of vehicle storage tanks. Both advances are necessary for the widespread adoption of fuel cell powertrains.”
Along this thinking, using all hydrogen in the beginning — without regard to its source — should also help “accelerate hydrogen infrastructure build-out.”
As far as setting up the refueling infrastructure is concerned, green hydrogen, blue hydrogen, and gray hydrogen are all the same. Indeed, gray hydrogen should be used first because it is already here and can easily help us set up and test the new delivery network. Once we have it in place and things are working, we can then shift to blue hydrogen and ultimately to green.
This is the sound way of doing things and the way we have done things before.
So stop conflating the source of the hydrogen with the means of delivering it. One has nothing to do with the other. Arguments against the source of hydrogen should not get in the way of us setting up a safe and efficient way to deliver it to those that need it.