Hydrogen With Seawater!
Hydrogen is only as clean as the energy source that’s used to make it, and green hydrogen only refers to hydrogen made using renewable energies. Gray hydrogen is the name for hydrogen made with fossil fuels.
Some people also include a third category – blue hydrogen – which is made from natural gas, making it a lower-emissions option compared to oil or coal. Currently, creating green hydrogen costs more than twice as much as gray hydrogen, at about $5 per kilogram.
Transitioning economy away from carbon-based fuels to green hydrogen would therefore require massive amounts of green energy and that other green stuff: cash. On top of economic issues, the International Energy Agency has said that diverting too much green energy away from other applications to be used in green hydrogen production would be counterproductive. In short: instead of solving the climate crisis, we’d just be moving resources and emissions around in a zero-sum game.
Another issue is that green hydrogen production requires massive quantities of pure water, which is an increasingly scarce resource. This means that scaling up green hydrogen production could seriously exacerbate already pressing global freshwater shortages. “Generating 1 kilogram of hydrogen using electrolysis takes some 10 kilograms of water,” Science recently reported. “Running trucks and key industries on green hydrogen could require roughly 25 billion cubic meters of fresh water a year, equivalent to the water consumption of a country with 62 million people.”
While these breakthroughs are extremely exciting, the water problem is just one of the many issues facing green hydrogen. Energy and cost are still enormous barriers to scaling up and scaling out the use of green hydrogen in widespread industrial applications. However, the work being done by these research groups are nonetheless a beacon of hope. If the water problem can be solved, it’s not inconceivable that, in due course, the other problems could be similarly mitigated. If the potential of green hydrogen is unlocked, it’s almost impossible to overstate the impact it would have on the climate, the economy, and the world.
