Coal Energy Storage Greentech. Photo by Dexter Fernandes via Unsplash
Lo and behold, the climate demonized coal has some greentech potential: Coal is generally not seen as a clean fuel source and is seen more as an energy slob – but coal could play a role in promoting greener energy.
Because American researchers from Penn State University have found that coal could be a good material for storing hydrogen gas – without a doubt one of the most promising clean fuel sources currently being explored.
Greentech potential of coal
There is no doubt that hydrogen shows promise as the clean energy source of the future (although it poses some potential problems). After all, when it is used as a fuel, only water is produced. However, an open question in connection with the use of hydrogen is the question of storage.
Hydrogen is highly flammable, and finding ways to safely store it has proven quite a challenge for researchers.
Green Storage Coal: Too bad to burn
While efforts are being made to encapsulate the gas in powders, pastes and cartridges, hydrogen storage solutions are currently more theory than practice. In the first category falls a surprising idea from researchers at Penn State University, who propose using coal — yes, coal — as a type of battery that could contain hydrogen.
Coal is known to be good at storing methane gas because it sticks to the material through a process known as adsorption. According to the researchers, this property of coal would also be transferred to hydrogen.
To test this theory, the research team built a special pressurization facility to force the hydrogen into the coal.
Coal Energy Storage Greentech. Photo Joey Harris Unsplash
Coal is a good hydrogen storage medium
By analyzing eight different types of coal from the United States, the researchers found that the material is indeed exceptionally good at storing hydrogen. The best results were obtained with the low-volatile hard coal from Virginia and the anthracite coal from Pennsylvania. Coal’s ability to trap gas is due to its unique composition.
According to the researchers, further research should deepen the potential of coal as a hydrogen container by examining the permeability and diffusivity of the material.
This should help understand how quickly hydrogen can be pumped in and out of different types of coal, which in turn could lead to efficient coal-based hydrogen batteries.