Pennsylvania State University has built a prototype plant for pumping hydrogen gas into and extracting it from coal. The idea is to use natural coal as a gas storage and thus store energy in it, instead of burning the coal itself. This approach could revolutionize the energy industry.
The modern “green policy” has hit coal mining hard, it is closing in many countries, although their coal reserves are still large. This creates problems for the economy. On the other hand, hydrogen is considered a promising energy source of the future, since it is easy to obtain and does not create harmful emissions when burned. But the storage of hydrogen on an industrial scale is a very difficult task that has not yet been solved.
It is wrong to consider coal as a mineral, in its structure it is more like a polymer made of carbon. It is like a porous sponge that can absorb a significant number of gas molecules, which is well known from the adsorption of methane by coal. The same can be done with hydrogen – but in practice it turned out to be quite difficult. It took years of research on how to process hydrogen, what pressure to apply, how to control the gas content inside coal, and so on.
At the moment, the technology of storing hydrogen in coal is not ready for practical application, but in the future it can become the basis of energy, as it will allow the use of natural materials in a new quality and in large quantities. This gives a chance to restore coal production while reducing emissions into the atmosphere.