This is exciting because it could reduce the capital expenditure needed for hydrogen production. The biggest reason we don't use intermittent electricity generation (wind, solar) for hydrogen production or desalination is that a significant fraction (~30%) of the total cost is capex.<p>The efficiency here is lower by a factor of 2 or 3 for electrical consumption (for now in the lab), but if you can get electricity at near zero cost for a few hours a day this could make economical sense.
The important metric for electrolysers now is not so much efficiency (although that's nice), it's capital cost. For use with intermittently available power capital cost becomes more important. This is different from the old notion of a hydrogen economy, using relatively expensive nuclear power to drive electrolysers 24/7.<p>It may also be nice if the electrolysers were reversible, so they could also act as fuel cells.
They are decreasing by a factor of 200, which means 1/200 of the starting amount.<p>English is not my native language so I was a bit confused by "200 times less", which I (wrongly) imagined to mean starting amount (x) minus 200x, getting to -199x, which didn't make sense. Math in speech is a tricky thing.
So... this is a fuel-cell-adjacent technology, and as such you need to read announcements like this with a somewhat cynical eye. I have no reason to doubt the science here. It probably works, or certainly is no less likely to fail than any other new technology.<p>But here's the thing: PEM electrolysis promises to reach hydrogen production efficiencies of... 80% or so, using exotic materials and entirely new chemistries. <i>Regular DC electrical electrolysis</i> (literally the "stick a wire in water to make bubbles" experiment we all did as kids) is starting out around the 65-70% mark. This just isn't that much better.<p>And doubly so when you realize that the most efficient reconversion of that hydrogen to electricity is going to lose another 20%.<p>This is better, but it's only incrementally better. 30% cheaper hydrogen would be nice, I guess, but it's not going to change any fundamentals of the energy economy.
Electrochemical cells (ie. Batteries and electrolyzers) are normally very efficient.<p>Ie. Normally they get about 90%-98% of the energy into the desired form.<p>So why are water-splitters so inefficient?
Green hydrogen in theory is valid and a very worthy target of research.<p>In practice it remains a FUD/policy distraction by petroleum interests to develop an energy ecosystem that is reliant on fossil fuels for the foreseeable (and profitable) future.<p>This is research that falls into the former category, but it's presence and other "green hydrogen" headlines in the news feed is due to the influence of the latter.<p>The economics of solar/wind/battery are and will be the driver of primary carbon reduction for the next decade, likely two decades.<p>Practical hydrogen has the same issue new nuclear has: what price target? LCOE and many other measures of solar/wind/battery have fallen at 10 percent or more per year for the last decade, and while "who knows" when that exponential curve tails off, looking at the scale of what's needed, forthcoming techs like perovskites and forthcoming production of sodium ion / LFP / LMFP and the prototypes of Lithium Sulfur / Solid State in batteries, there is likely another decade of improvement at those rates.<p>So like "new nuclear", sure, keep up the research, and if price competitive applications can compete with sodium ion batteries (which I think will be a killer app in grid storage based on the materials and gravimetric densities), sure, but I think these techs will be kind of like magnetic RAM vs DRAM: it simply missed the boat of the economies of scale rampup, and now has to wait for that curve to stabilize before anything competitive can crop up.<p>For hydrogen to be practical in any green form in large scale requires a huge development in generation (which this is), storage, transport, and infrastructure. Fundamentally that hydrogen creation/transport/storage/delivery infrastructure, which is 99.99999% unbuilt, competes with the existing power grid, which likely has TRILLIONS of dollars in accumulated investment and will receive likely another trillion or two globally over the next two years to adapt to dirt cheap solar and wind, to say nothing of what will be invested in home / commercial distributed solar generation and battery storage which hydrogen is not applicable.<p>Big Oil had a chance when the Bush Administration was talking about hydrogen circa 2003. But the fat cats sat on their hats, and Tesla and solar/wind left them in their dust. The only ones really pushing hydrogen are those and Toyota, who perplexingly missed the EV boat despite releasing hybrids in 1997 and should have been providing an entire product line of PHEVs by 2005 that pushed the entire industry towards PHEVs for all consumer transport by 2015. We'd be immune to OPEC and russia if that had happened, and 70-80% of daily miles would be electric with no range anxiety.