Hydrogen holds important promise as a cleaner alternative to fossil fuels.
But as governments and companies pour tens of billions of dollars into hydrogen energy technologies, we need to make sure that we’re asking the hard questions that we should be asking about this emerging industry.
Hydrogen is a leak-prone gas with a potent warming effect that’s widely overlooked. To be an effective climate solution, hydrogen must be produced cleanly and used wisely.
With the industry in its infancy, now is the time to address problems and get things right — before vast systems and infrastructure are built out. Here are three big concerns to stay focused on:
Most people don’t realize that hydrogen can trigger warming: When hydrogen escapes into the atmosphere before it’s burned or used, it reacts with other chemicals to create warming effects.
We’re just starting to understand how potent those effects can be. Research by EDF scientists found that on time scales of a decade or two, hydrogen’s warming power is much greater than previously recognized.
This poses a challenge for industry: Because hydrogen molecules are tiny, they’re prone to leakage.
All of this means minimizing leaks must be a priority for every hydrogen project. Good engineering, regular inspections, and eliminating venting are crucial (which is why EDF is also working with developers to create better detection technology for hydrogen).
And the further hydrogen travels, the greater the risk of leaks, so it makes sense to produce hydrogen close to where it’s used
Hydrogen does not naturally occur on its own; it must be separated from other elements. As it’s typically done today, that process is energy-intensive and creates a lot of climate pollution.
But “green” hydrogen can be made by using renewable energy, and “blue” hydrogen by extracting it from natural gas that’s produced under conditions that sharply minimize methane and CO2 emissions.
In a well-managed system with low leak rates, our researchers found that both green hydrogen and — to a lesser extent — the best blue hydrogen would significantly reduce warming compared with fossil fuels.
With high leak rates, green hydrogen would still be better for the climate over 20 years than fossil fuels, but far less so than the climate-neutral promises we often hear.
But for blue hydrogen, if leakage of both hydrogen and natural gas is high, this type of hydrogen could actually increase the 20-year warming impact.
If hydrogen production and distribution systems aren’t managed properly, even supposedly “clean” hydrogen could be worse for the climate in the near term than the fossil fuels it replaces.
People’s health and well-being must be a priority as new energy sources are developed. Hydrogen is no solution at all if it harms local communities.
Water consumption and air pollution from production and use of hydrogen must factor into deployment decisions. If hydrogen is burned in a power plant, it can produce air pollutants called nitrogen oxides that have been linked to asthma.
Blue hydrogen projects may also prolong the life of existing fossil fuel infrastructure that has polluted communities for decades. People living nearby must be engaged from the start, and new projects must adapt to local concerns.
In the global transition to clean energy, the best uses for hydrogen will be in places where clean electricity can’t do the job alone.
Hydrogen could be especially useful in heavy industry — like steel and cement production — or as a raw material for low-carbon fuels for ships and planes.
But in most cases, it won’t make sense to divert electricity from the grid to make hydrogen for use in cars, homes or commercial buildings. Electricity can serve those needs directly — faster, more easily and at less cost.
The green electricity necessary to make green hydrogen is currently a scarce commodity — and likely to be so for decades. So before we start making big bets on hydrogen, we’ll need a major commitment to the deployment of renewable energy (and in many cases, it will make more sense to use that electricity directly).
Making blue hydrogen from gas requires not only preventing methane emissions, but also capturing and permanently sequestering the associated carbon dioxide — for which there is currently almost no significant capacity.
We’re far from where we need to be to make clean hydrogen. But with the industry growing, it’s a good time to ask tough questions. Decisions made today will help ensure that global investments in hydrogen deliver on their promise.