Coal as a geological hydrogen battery: A promising breakthrough in clean energy storage

Study reveals coal's potential as a game-changing hydrogen storage solution


Researchers propose using coal as a potential solution to the storage challenges of hydrogen gas, similar to how batteries store energy for future use, according to a recent study. The study, published in the journal Applied Energy, highlights the potential of coal as a geological hydrogen battery, addressing a major obstacle in establishing a sustainable clean energy supply chain.

Hydrogen, known for its clean-burning properties, holds great promise for meeting the energy demands of transportation, electricity generation, and manufacturing sectors. However, the lack of a cost-effective and efficient hydrogen storage method has hindered its widespread adoption.

Scientists from Penn State University, led by Associate Professor Shimin Liu, suggest that coal, with its well-established infrastructure and extensive knowledge base, could serve as a suitable medium for geological hydrogen storage. By injecting and storing hydrogen in geologic formations, large quantities can be stored to meet fluctuating energy demands.

In their study, the researchers analysed eight different types of coal from various coalfields across the United States to evaluate their sorption and diffusion potential—their ability to capture and retain hydrogen. The results indicated that all eight coals exhibited significant sorption properties, with low-volatile bituminous coal from eastern Virginia and anthracite coal from eastern Pennsylvania demonstrating the highest performance in tests.

Liu expressed optimism about coal's potential for geological hydrogen storage, citing its superior capacity, existing infrastructure, and widespread availability. He also highlighted depleted coalbed methane reservoirs as ideal candidates due to their unconventional natural gas content, primarily methane, which adheres to the surface of the coal through a process called adsorption.

While the findings offer a promising avenue for advancing clean energy, further research and development are necessary to realize the full potential of hydrogen storage in coal. The study contributes to the ongoing efforts to understand the feasibility and practicality of using coal as a means of storing hydrogen on a larger scale.

The concept of utilising coal as a geological hydrogen battery is particularly intriguing due to the extensive knowledge and experience gained from commercial coal gas production over the past several decades. Coal has proven to be a reliable energy resource, and leveraging its existing infrastructure for hydrogen storage could significantly accelerate the transition to a clean energy economy.

Moreover, the researchers emphasize that coal outperforms other potential storage formations in terms of its storage capacity, availability, and compatibility with existing infrastructure. This makes it a logical choice for geological hydrogen storage.

By capitalising on depleted coalbed methane reservoirs, which have already played a crucial role in fossil fuel extraction, the researchers propose repurposing these reservoirs for hydrogen storage. The methane that naturally adheres to the coal surface can be replaced by hydrogen through the process of adsorption. This not only provides a sustainable use for these depleted reservoirs but also facilitates the integration of hydrogen storage into established energy systems.

The implications of this study are significant for the advancement of clean energy technologies. If further research and development confirm the feasibility and viability of storing hydrogen in coal, it could address one of the major hurdles in the widespread adoption of hydrogen as a clean and sustainable fuel source. The ability to store large quantities of hydrogen in geologic formations would ensure a reliable supply of energy to meet fluctuating demands, paving the way for greater utilisation of hydrogen in transportation, electricity generation, and manufacturing sectors.

As the world continues to seek innovative solutions to combat climate change and reduce greenhouse gas emissions, the exploration of unconventional methods such as storing hydrogen in coal demonstrates the commitment to finding practical and sustainable alternatives. With ongoing advancements in clean energy technologies, the prospect of coal serving as a geological hydrogen battery brings us one step closer to achieving a cleaner and greener future.