Hydrogen's Hidden Impact on Underground Storage

Hydrogen has a big role in energy, but it's also food for tiny organisms underground. When hydrogen is stored beneath the surface, these microorganisms use it as a power source. This can lead to problems, like the formation of biofilms. Biofilms are like slimy layers of bacteria that can clog up the system and mess with the flow of hydrogen. This can make storing hydrogen less efficient. Scientists looked into how different food sources affect a specific type of bacteria, Oleidesulfovibrio alaskensis. They found that when this bacteria has lactate to eat, it creates strong biofilms. These biofilms can cause bioclogging, which is like a traffic jam for hydrogen. On the other hand, when the bacteria has hydrogen to eat, it moves around more and doesn't produce as much biofilm. This is because the bacteria seems to prefer floating around freely rather than sticking to surfaces. The study also showed that injecting hydrogen multiple times can help reduce the risk of bioclogging. After three hydrogen injections, 69% of the biofilm detached, compared to only 31% with nitrogen injections. This suggests that using hydrogen might be a better option for underground storage, as it reduces the risk of pore blockage caused by bacterial growth. However, it's important to note that this study only looked at one type of bacteria. The real world is much more complex, with many different types of microorganisms interacting with each other. Therefore, more research is needed to fully understand the impact of hydrogen on underground storage. Also, the study did not account for the potential long-term effects of repeated hydrogen injections on the subsurface environment. This is a critical gap that needs to be addressed in future studies. It's also worth considering the broader implications of using hydrogen as an energy source. While it has the potential to be a clean and renewable energy carrier, it's important to weigh the benefits against the potential risks, such as the impact on subsurface microbial communities and the environment.