The world is increasingly banking on green hydrogen fuel to fill some of the critical missing pieces in the clean-energy puzzle.
US presidential candidate Joe Biden’s climate plan calls for a research program to produce a clean form of the gas that’s cheap enough to fuel power plants within a decade. Likewise, Japan, South Korea, Australia, New Zealand, and the European Union have all published hydrogen roadmaps that rely on it to accelerate greenhouse gas reductions in the power, transportation, or
The attraction is obvious: hydrogen, the most abundant element in the universe, could fuel our vehicles, power our electricity plants, and provide a way to store renewable energy without pumping out the carbon dioxide driving climate change or other pollutants (its only byproduct from cars and trucks is water). But while researchers have trumpeted the promise of a “hydrogen economy” for decades, it’s barely made a dent in fossil fuel demand, and nearly all of it is still produced through a carbon polluting process involving natural gas.
The grand vision of the hydrogen economy has been held back by the high costs of creating a clean version, the massive investments into vehicles, machines and pipes that could be required to put it to use, and progress in competing energy storage alternatives like batteries.
So what’s driving the renewed interest?
For one thing, the economics are rapidly changing. We can produce hydrogen directly by simply splitting water, in a process known as electrolysis, but it’s been prohibitively expensive in large part because it requires a lot of electricity. As the price of solar and wind power continues to rapidly decline, however, it will begin to look far more feasible.
At the same time, as more nations do the hard math on how to achieve their aggressive emissions targets in the coming decades, a green form of hydrogen increasingly seems crucial, says Joan Ogden, director of the sustainable transportation energy pathway program at the University of California, Davis. It’s a flexible tool that could help to clean up an array of sectors where we still don’t have affordable and ready solutions, like aviation, shipping, fertilizer production, and long-duration energy storage for the electricity grid.
Falling renewables costs
For now, however, clean hydrogen is far too expensive in most situations. A recent paper found that relying on solar power to run the electrolyzers that split water can run six times higher than the natural gas process, known as steam methane reforming.
There are plenty of energy experts who maintain that the added costs and complexities of producing, storing and using a clean version means it will never really take off beyond marginal use cases.
But the good news is that electricity itself makes up a huge share of the cost—upwards of 60% or more—and, again, the costs of renewables are falling fast. Meanwhile, the costs of electrolyzers themselves are projected to decline steeply as manufacturers scale up production, and various research groups develop advanced versions of the technology.
A Nature Energy paper early last year found that if market trends continue, green hydrogen could be economically competitive on an industrial scale within a decade. Similarly, the International Energy Agency projects that the cost of clean hydrogen will fall 30% by 2030.
Source: MIT Technology Review