Global warming is intensifying, and the UN Secretary General has already warned – in a very metaphorical way, by the way – that we have crossed a point of no return. However, one of our main assets to fight it, hydrogen, could become our worst enemy: here is the latest serious warning from the experts.
Even hydrogen has a flip side: is it really good for the planet?
Hydrogen is often portrayed as a climate-friendly fuel of the future. The idea is that hydrogen can be produced in a low-emission way, used as a clean fuel source, and any emissions would be water vapor.
This makes hydrogen appealing as a solution to reduce greenhouse gas emissions from difficult-to-electrify sectors like heavy industry and transportation. However, some scientists now warn that hydrogen may not be as clean as previously thought.
There are concerns that hydrogen leaks and accidental releases could worsen global warming in the short term. Although hydrogen does not directly trap heat like carbon dioxide and methane, it could still contribute significantly to climate change if the infrastructure to produce and transport hydrogen results in increased emissions.
Experts’ warning: hydrogen will aggravate global warming if we do this
While hydrogen is often promoted as a clean fuel, scientists warn that leaks of hydrogen could actually accelerate global warming. Hydrogen is not inherently clean or carbon-free. When hydrogen is created via methane reforming or from fossil fuels, it generates substantial carbon emissions.
Even if made via electrolysis with renewable energy, any leakage of hydrogen into the atmosphere can worsen climate change. Hydrogen is a potent greenhouse gas, with more than 25 times the global warming potential of carbon dioxide over a 100-year period.
Scientists estimate that to achieve net-zero emissions, any leakage throughout the hydrogen supply chain must remain below 3-4%. However, studies show leakage rates today can range from 3-20% from production to end use.
As long as fossil fuels are used to produce hydrogen, any amount of leakage makes its climate benefits questionable at best. The risk is that expanding hydrogen infrastructure with pipelines and storage could lead to increased leaks over time.
Infrastructure doesn’t help either: an added problem for hydrogen
While hydrogen is abundant, capturing and transporting hydrogen comes with many challenges. Unlike fuels like natural gas and oil which can be transported via pipelines, hydrogen’s small molecular size makes it prone to leakage. Hydrogen pipelines and storage tanks require special materials and designs to prevent gas escape.
Retrofitting natural gas pipelines for hydrogen risks increased leakage at joints, valves, and seals unless fully upgraded. Pipeline corrosion is also a concern, as hydrogen can embrittle some metals. New hydrogen pipelines are estimated to cost 2-3 times more than for natural gas.
Underground storage in salt caverns and aquifers can contain large volumes of hydrogen, but leakage remains an issue. Storage tanks and other hydrogen infrastructure similarly require advanced materials to minimize losses.
With so much potential for leaks across pipes, tanks, valves and equipment, hydrogen infrastructure poses risks that could negate climate benefits compared to direct electrification. Strict standards and practices are needed to transition safely while avoiding increased emissions.
Once again, we see how the relationship between global warming and hydrogen is not what we would like it to be. The planet needs a clean, serious, and decisive ecological transition, without half solutions such as brown, gray, or even black hydrogen. Do you understand why the situation is so serious? Over the next few years, we will see if the experts’ warnings come true.