New Zealand research looks to underground hydrogen

The models are designed to simulate the complex processes involved in hydrogen storage, said PhD candidate Liu Jinjian of the University of Canterbury (UC).

"They help us predict what might happen, identify potential challenges, and determine practical solutions for hydrogen extraction," said Liu who conducted the research supervised by UC Associate Professor David Dempsey.

While storing natural gas underground is standard, it is also less complex because it is in its natural environment. Using the same process for hydrogen is a comparative unknown but it may end up being critical to whether New Zealand has a hydrogen future, according to the study.

The research highlights critical operational considerations, such as managing reservoir pressure, minimizing hydrogen loss, and maintaining gas purity, Liu said, citing an example that the site's unique geology allows hydrogen to sit buoyantly in "cups" within the reservoir, but excessive injection risks spillover.

There are, however, multiple complex considerations to make hydrogen viable at even one location.

"One challenge already identified is contamination during extraction, as hydrogen often mixes with residual natural gas or water. While this mixture may complicate some applications, it could still be viable for power generation or certain chemical processes," Dempsey said, Xinhua news agency reported.

Hydrogen storage at scale could act as a buffer, much like reservoirs do for water, he said, adding the goal is to develop a framework that can be applied to various sites nationwide, optimizing storage and minimizing transport challenges.

"Injecting hydrogen underground requires careful timing and precision. When green hydrogen is produced - say, during periods of surplus solar energy - it must be stored if we later want to capture its full value. Similarly, being able to retrieve it rapidly during peak demand is just as important," says Professor Dempsey.