In green technology circles, just mentioning the word is enough to start an argument.
Hydrogen could become a ubiquitous source of electricity and heat, say advocates. By stripping away the sole electron that swirls around the atom’s nucleus, a hydrogen fuel cell can produce electricity (and heat if desired) with a lot less energy and noise than a coal plant. You also don’t need to rely on the grid: hydrogen gas can be converted to power in a fuel cell in your basement. Unlike coal plants, fuel cells do not emit greenhouse gases: water vapor is the byproduct.
Plus, it’s somewhat prevalent. Hydrogen remains the most abundant element in the universe and every molecule of water contains two hydrogens.
Some car makers—Toyota, Honda, Mercedes—argue that hydrogen fuel cells will ultimately wind up in vehicles, and thereby reduce both the weight and cost of these cars. Hydrogen cars would also eliminate the pain of charging. It takes three to eight hours to charge car batteries: filling a car’s tank with hydrogen takes five minutes. (Note: hydrogen fuel cell cars are electric cars, but instead of charging the batteries from a plug, the power comes from the fuel cell.)
Because hydrogen can sit in a tank next to a fuel cell without dissipating, hydrogen really acts as both a source of energy and an energy storage technology.
Now let’s cue to ugly reality. While hydrogen fuel cells don’t generate carbon emissions directly, producing hydrogen today is a dirty business. Most chemical companies make it by breaking up methane molecules: every kilogram of hydrogen produced through this process results in 9.3 kilograms of carbon dioxide, which typically gets released into the atmosphere.
Pulling hydrogen from water molecules requires, in most circumstances, tremendous amounts of energy. Some have suggested that the only way to make it economical is to harness the waste heat from nuclear power plants. But that would require more power plants.
Then there is transportation. We don’t have a network of hydrogen pipelines. Hydrogen filling stations don’t exist either. The infrastructure build out would require far more construction and more scientific breakthroughs than adding EV charging stations to the grid.
Fuel cells–which depend on expensive materials like platinum–remain in the experimental stage too. I’ve driven a few hydrogen powered cars. They are the best-driving, smoothest-handling cars I’ve ever experienced. I asked a company representative how much they cost. “Probably a million,” she estimated. The Hydrogen Highway leads to one place: a dead end.
But back to the advocates. Hope springs eternal. At MIT, Daniel Nocera has identified a chemical catalyst that can reduce the amount of energy required to strip hydrogen from water molecules. Sun Catalytix, his company, dreams of homes equipped with solar panels that provide the energy to produce hydrogen power for home fuel cells.
Others, like SignaChem, have come up with dry chemical pellets: put them in water and hydrogen results. If you distributed these pellets by crates, you’d eliminate–at least partly–the need for hydrogen filling stations or pipelines in theory.
Hydrogen advocates–and there are fewer of them than there were even three years ago–readily admit the technology has not lived up to promise. Virtually all of the experience to date favors the critics.
But still, the tantalizing possibility beckons. Maybe in 2020 cheap membranes will appear. Maybe by then the chemical catalysts will be perfected.
Maybe…and maybe not.
What do you think?
Michael Kanellos is the Editor in Chief at Greentech Media, where he covers emerging technologies and companies in the green world. He has appeared on 60 Minutes, NPR, Al Jazeera, Fox News among other media outlets and speaks often at tech conferences. A graduate of Cornell University and the University of California, he has worked as an attorney, a travel writer and a busboy at a pancake house.