Global warming is becoming a growing problem, with the UN Secretary-General warning that we may have passed a tipping point where it cannot be reversed. However, experts are warning that hydrogen, one of the key resources in the fight against global warming, could now be a potential threat.
Hydrogen, often hailed as the climate-friendly energy of the future, is thought to be produced in a low-emissions way and used as a clean energy source, with the only emission being water vapour. This makes it a potential solution to reducing greenhouse gas emissions in areas that are difficult to electrify, such as heavy industry and transport. However, some scientists are now warning that hydrogen may not be as clean as expected.
There are concerns that leaks and accidental emissions of hydrogen could exacerbate global warming in the short term. Although hydrogen itself does not directly absorb heat like carbon dioxide and methane, it could still have a significant impact on climate change if the infrastructure used to produce and transport it leads to increased emissions.
Experts warn that hydrogen could exacerbate global warming if we continue on our current path. Although hydrogen is often touted as a clean fuel, scientists say leaks could actually accelerate global warming. Hydrogen is not inherently clean or carbon-free. When hydrogen is produced, either through methane reforming or from fossil fuels, it generates large amounts of carbon emissions.
Even when hydrogen is produced through electrolysis using renewable energy, hydrogen leaks into the atmosphere can exacerbate climate change. Hydrogen is a potent greenhouse gas, with a global warming potential more than 25 times that of carbon dioxide over a hundred years. Scientists estimate that to achieve net zero emissions, leakage rates throughout the hydrogen supply chain must be kept below 3-4%. However, existing studies suggest that leakage rates from production to end use could be between 3-20%.
As long as fossil fuels are used to produce hydrogen, any amount of leakage is enough to make the climate benefits uncertain. The risk is that hydrogen infrastructure could lead to increased leakage over time as pipelines and storage facilities expand.
Another problem with hydrogen is that, despite its abundance, it is challenging to capture and transport. Unlike fuels such as natural gas and oil that can be transported by pipeline, hydrogen has a smaller molecule size and is prone to leaks. Hydrogen pipelines and storage tanks require special materials and designs to prevent gas leaks. Modifying natural gas pipelines to carry hydrogen increases the risk of leaks from joints, valves and seals unless they are fully upgraded. Pipeline corrosion is also a problem, as hydrogen makes certain metals brittle. It is estimated that new hydrogen pipelines cost 2-3 times more than natural gas pipelines.
Underground storage facilities in salt caverns and aquifers can hold large amounts of hydrogen, but leaks remain a problem. Tanks and other hydrogen infrastructure also need to use advanced materials to minimize losses.
Given the high risk of leaks in pipelines, tanks, valves and equipment, the risks of hydrogen infrastructure could offset its potential climate benefits compared to direct electrification. Therefore, strict standards and practices are needed to ensure a safe transition and avoid increased emissions.
Once again, we are reminded that the relationship between global warming and hydrogen is not as simple as we expected. The planet needs a clean, serious and decisive ecological transition, not half-hearted solutions such as brown, grey or even black hydrogen. Do you understand the seriousness of the situation? In the next few years, we will see whether the experts' warnings will become a reality.
