A lot has changed since 2004, when Joe Romm first penned The Hype About Hydrogen, but not enough. Hydrogen is still being lauded as a near-magical energy panacea by governments, fossil fuel giants, and far too many breathless media headlines. And yet, nearly two decades of innovation, investment, and infrastructure later, the hard truths about hydrogen remain almost embarrassingly unchanged. Worse, the louder the hype, the greater the risk we squander precious time and money chasing the wrong solution.
Joe was kind enough to send me the updated and revised edition of his book, and I’ve just finished reading it. I’d encourage anyone who cares about energy, climate, and policy integrity to do the same. It’s a masterclass in separating signal from noise.
But this post isn’t a book review. It’s a call to recalibrate, urgently, how we think about hydrogen in the climate fight. It’s time to stop framing it as a silver bullet and start treating it as a scalpel: a targeted tool, for niche applications, deployed only where cleaner, cheaper, more efficient options genuinely don’t exist.
The Inefficiency Elephant in the Room
Let’s start with the physics. Producing hydrogen from water using electrolysis powered by renewable electricity sounds elegant. But reality bites hard. Green hydrogen has a round-trip efficiency of just 20–30% in most use cases. Compare that to battery electric systems, which routinely top 80%.
So if you start with 100 units of renewable electricity, run it through electrolysis to produce hydrogen, compress it, transport it, then convert it back into electricity via a fuel cell? You’re lucky to get 20–25 units out the other end. That’s a 75–80% energy loss. You can get roughly four times the mileage from the same renewable input by going direct-to-battery. It’s like turning renewable champagne into soda water, then trying to sell it at a premium.
This is not a minor footnote. It is the whole story. In a carbon-constrained world where we need to electrify everything, wasting 75% of your green electrons just to mimic a solution that already exists (electricity!) is not just bad engineering. It’s bad climate strategy. In fact, it’s insanity!
Hydrogen’s Real Role: Feedstock, Not Fuel
To be clear, hydrogen is indispensable. We need it to make ammonia for fertiliser, to refine metals, to produce methanol, and for other chemical and industrial processes. This is where hydrogen already plays a major role, and it’s responsible for about 2% of global CO2 emissions.
Here, green hydrogen can help. Replacing grey hydrogen (made from unabated methane) with electrolytic green hydrogen is a good use of renewables. But let’s be honest about the scale: even fully decarbonising current hydrogen feedstock applications would shave only a few percent off global emissions. Necessary? Yes. Transformative? No.
Where hydrogen becomes fantasy is when it’s proposed as a fuel for passenger cars, home heating, or short-haul aviation. Let’s walk through some examples.
The Market Has Already Spoken
Passenger vehicles? Battery electric vehicles (BEVs) have won. Full stop. In 2024, EVs outsold hydrogen fuel cell vehicles by a factor of nearly 1,700 to 1 globally. Even in South Korea, one of the few countries pushing hydrogen cars, hydrogen vehicle registrations fell 54% in 2023, compared to 2022, while EVs surged.
Heavy-duty trucking? The early promise of hydrogen trucks is running into the same wall: infrastructure and efficiency. Companies like Daimler, Traton Group (Scania and Man) and Volvo are rolling out battery-electric HGVs with growing range and performance. And every time a kilowatt-hour goes into a hydrogen production facility instead of directly into a truck battery, it costs more, emits more, and delays decarbonisation.
Heating buildings? Numerous studies have found you need 5–6 times more electricity to heat a home with hydrogen than with a heat pump. The European Union’s own analysis agrees. Hydrogen heating is a thermodynamic facepalm.
Blue Hydrogen: A Fossil-Fuel Trojan Horse
Perhaps the most concerning development is the PR rebranding of “blue hydrogen” – hydrogen produced from natural gas using steam methane reforming with carbon capture and storage (CCS). The fossil fuel industry loves this one. Why? Because it lets them keep drilling and selling methane, slapping a “low-carbon” label on it, and collecting government subsidies for the privilege.
But blue hydrogen is riddled with problems. Methane leaks during extraction and transport dramatically undercut its climate value. Carbon capture rarely captures as much CO2 as promised. And even when it does, much of the captured CO2 is used for enhanced oil recovery, which just means more oil gets burned. That’s not climate mitigation. That’s carbon laundering.
A peer-reviewed study from Cornell in 2021 found blue hydrogen may actually be worse for the climate than burning coal.
The Hydrogen Gold Rush: A Massive Opportunity Cost
We’re not just wasting money on hydrogen hype. We’re diverting renewables that could be decarbonising sectors today.
Every gigawatt of solar that gets allocated to green hydrogen production instead of powering electric heat pumps, EVs, or grid-scale batteries is a lost opportunity to cut emissions more cheaply, more deeply, and more quickly.
We don’t have the luxury of throwing 80% of our electrons away. The 2020s are supposed to be the decisive decade for climate action. We need to prioritise solutions that scale, now.
So Where Does Hydrogen Make Sense?
There are hard-to-electrify sectors where hydrogen (or hydrogen-derived fuels) could play a role:
- Steelmaking: Hydrogen-based direct reduced iron (H-DRI) could replace coal in primary steel production, though the economics are still shaky.
- Aviation: Synthetic fuels made from green hydrogen and captured CO2 could help decarbonise long-haul aviation, albeit at high cost (though, as discussed on a recent episode of the Climate Confident podcast, SAF may be a better option).
- Shipping: Ammonia and methanol as shipping fuels show some promise, but they’re also highly inefficient.
Even in these sectors, electrification (via synthetic fuels, direct electrification, or operational changes) often outcompetes hydrogen when lifecycle costs and energy efficiency are accounted for.
Time to Get Real
Hydrogen is not the enemy. But hydrogen hype is.
If we treat hydrogen as the hero of the net-zero story, we lose. We lose time, we lose money, and most critically, we lose the race to keep warming below catastrophic levels.
But if we treat hydrogen like what it is, a niche solution for very specific challenges, and direct our real firepower toward mass electrification, grid modernisation, storage deployment, and demand flexibility? Then we have a fighting chance.
So here’s the message to policymakers, boardrooms, investors, and the cleantech community:
Stop subsidising hydrogen cars. Stop blending hydrogen into gas networks. Stop building blue hydrogen boondoggles.
Start investing in electrification. Start regulating methane. Start measuring opportunity cost. And start reading books that challenge the status quo.
Final Thoughts
Joe Romm’s updated The Hype About Hydrogen is a sobering, evidence-rich reality check. It’s not anti-hydrogen. It’s anti-distraction. And in a climate emergency, distraction is deadly.
If you’re serious about energy policy, serious about emissions reductions, and serious about making sure our resources go where they’ll do the most good, get yourself a copy. Read it. Share it. Challenge every shiny hydrogen press release you see with the simple question: what’s the opportunity cost?
Full disclosure: Joe Romm sent me a free copy of the book for review.