Why is the Creation of Hydrogen and Hydrogen Fuel Cells so Inefficient?

Date
11/29/2021

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A company called DiviGas just received $3.6 million in a seed round, with promises to “clean up the hydrogen production industry.” So is hydrogen ready for its (mainstream) debut at Carnegie Hall? Not quite.

The hydrogen fuel cell isn’t exactly breaking news – a primitive version was touted by England’s Sir Humphry Davy way back in 1801, but the first modern application was an Allis-Chalmers farm tractor fitted with a 15 kW fuel cell in 1959.

62 years later, hydrogen fuel cells still haven’t entered mainstream usage, and there’s a good reason for that (several good reasons, in fact).

Hydrogen is intrinsically inefficient as a combustion fuel source because, for us hapless Earthlings, it doesn’t occur freely in nature in useful quantities (the sun derives its energy from hydrogen-based nuclear fusion, but that’s not easily replicable on Earth, and the entire notion opens a whole different can of worms).

As Stanford points out, hydrogen must be painstakingly created on the third planet from the sun, usually by splitting H2O to get the hydrogen. And as they point out, “This requires all the energy you are going to get from burning the hydrogen and a bit more on account of inefficiencies.” 

This makes hydrogen an energy transfer medium (and a particularly inefficient one) rather than a primary source, and since it’s obtained by splitting H2O into hydrogen and water, it’s not unreasonable to conclude that nuclear energy should be used to split the water (which is exactly what Stanford suggests).

Stanford’s author denied that “powering cars with liquid hydrogen produced by nuclear reactors is the best solution” (emphasis), but he does feel it’s an adequate one.

So while nuclear energy won’t completely dissolve the creation of hydrogen and hydrogen fuel cells of their inefficiencies, it could help shore them up. And as the authors point out, solar carries no social stigmas and it could also be used to split H2O, but it’s not nearly as effective as nuclear energy, which does have crippling social taboos.

But why is the creation of hydrogen fuel cells so inefficient in the first place? Back in 2013, Volkswagen’s Rudolf Kreb perfectly summarized the inherent inefficiencies of hydrogen cars (and why many experts predict hydrogen fuel cells won’t be fully viable for cars until mid-century):

“Hydrogen mobility only makes sense if you use green energy," Kreb said at the 2013 LA Auto Show. And when you initially convert it into hydrogen, "you lose about 40 percent of the initial energy," he said. “Then, you have to compress the hydrogen to 700 bar and store it in the vehicle, which costs more energy. And then you have to convert the hydrogen back to electricity in a fuel cell with another efficiency loss," he said, "so that in the end, from your original 100 percent of electric energy, you end up with 30 to 40 percent."

To bring this back to Divigas, the company claims their new polymeric membrane, Divi-H, can purify Hydrogen up to 99.95% purity from any feedstock composition, and the founders are describing their solution as a viable third choice against an emissions-heavy expensive option and a cheap, limited one.

As far as commercial viability, co-founder and CTO Ali Naderi explained that, “This type of membrane can be fabricated commercially by using a customized spinning line that has the same price as a standard spinning line has.”

We’ll see whether the company’s new polymeric membrane can help fix the intrinsic inefficiencies in the creation of hydrogen and hydrogen fuel cells.

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