In the first half of this pair of articles on the challenges of internecine squabbling among those focused on replacing fossil fuels, I covered the $39 trillion worth of reasons why the fossil fuel industry is trying incredibly hard to pretend that it has a future as an energy delivery industry, why electrification is the answer to almost everything, and why biofuels are the answers to what electricity can’t do.
Now it’s time for hydrogen and synthetic fuels.
Next we have hydrogen. Hydrogen is indeed the most abundant element in the universe, however, the thing that isn’t said clearly is that it’s tightly chemically bound to other things, and doesn’t float around freely in a harvestable form. And it does indeed have a high energy density by mass, but unfortunately it has a terrible energy density by volume, which more than counterbalances the mass side of the equation. We have to get it from fossil fuels, which are, after all, hydrocarbons, or from water, which is two hydrogens and an oxygen. Both of those things require a lot of energy, and there are a bunch of negative externalities for several of the processes.
First off, there’s black, gray, and blue hydrogen. About 99% of all hydrogen created and used today comes from fossil fuels, and it’s black. Making hydrogen from natural gas produces 10x the mass of CO2 as of produced hydrogen. Making hydrogen from coal produces 20–35x the mass of CO2 as of hydrogen. End to end, because of process efficiencies, methane leakage, and the like, more greenhouse gases are created for the energy in hydrogen than if we just used the fossil fuels directly.
The false promise of blue hydrogen is that all of those negative externalities will be centralized into a gas reformation or coal gasification facility, where the CO2 can be captured as it is emitted, and the chemical and particulate pollution can be scrubbed sufficiently from the effluents. The $39 trillion in profits fossil fuel industry really, really loves this, because it means that they can keep an enormous amount of their revenue and profits, as long as someone else pays for the capture and sequestration of the CO2 and other pollutants. As a result, there’s an awful lot of fossil fuel money and lobbying pushing hard for a hydrogen economy.
And as stated, carbon capture and sequestration is a money pit of extremely limited value. 50 years of investment in CCS has resulted in the biggest CCS ‘wins’ pumping CO2 out of the ground in one place and pumping it back into the ground in another, typically with lots of government money, and almost entirely for enhanced oil recovery, which produces more CO2 than was sequestered. The total scale of all carbon capture and use globally is five to seven orders of magnitude off the scale of our CO2 emissions problem. Making hydrogen from fossil fuels just makes the CO2 emissions higher, and the scale problem just gets worse. You can understand why the fossil fuel industry doesn’t like that part of the story being told.
The second form of hydrogen is green hydrogen. In this pathway, renewable electricity is used to electrolyze water into hydrogen and oxygen, putting energy in to break the chemical bonds and get hydrogen out. Then the hydrogen can be compressed to ten thousand pounds per square inch to get it down to a usable volume, or chilled to 24 degrees above absolute zero to turn it into a somewhat manageable liquid.
Hydrogen burns fairly cleanly, combusting with oxygen to make water again. However, burning hydrogen creates the nitrous oxides mentioned above, as burning anything in our atmosphere does. That’s because nitrogen is 78% of the atmosphere and oxygen is 21%. Burning anything releases heat and causes the nitrogen and oxygen from the air to combine in various ways, with the associated negative externalities of smog-precursors and high global warming potential gases.
Hydrogen fuel cells are like electrolyzers run in reverse. Instead of burning hydrogen, you run it through the cell, recombine it with oxygen and get some energy and waste heat from the process, but without nitrous oxides, which is nice.
The problem with green hydrogen is that it’s both inefficient and ineffective. Creating hydrogen from water loses at minimum 20% of the energy required for the process. Compressing and/or chilling it loses more. Transporting it is inefficient, with piping it, for example, taking three times the energy as for natural gas. When it’s burned, it’s like fossil fuels in that we get relatively low grade heat back, which means waste heat and entropy. Burning it for heat produces nitrous oxides still, and unless you directly need heat, converting it to electricity has a bunch of losses. Hydrogen fuel cells produce waste heat and at best are 60% efficient at getting the remaining energy out.
Hydrogen has some other problems for distribution. It embrittles harder steels, so a lot of existing pipelines and pumps can’t be reused and would have to be replaced at great expense. And electronics don’t like hydrogen much, so in many places the electronics for monitoring and controlling distribution have to be replaced too. And for use, hydrogen doesn’t directly replace natural gas in appliances, so brand new appliances — which don’t exist as manufactured commodity items today, by the way — must be purchased and installed.
Electricity turns into heat or mechanical energy for motion very efficiently. But the same ‘energy’ of heat, unless it’s extremely hot, doesn’t turn into mechanical energy efficiently. The technical term is exergy, which is the percentage of the energy in something which can actually be usefully used. Low grade heat has poor exergy, while electricity has high exergy.
Electrification types, like me, point out that all of that inefficiency and ineffectiveness is avoided by using the electricity from renewables more directly. Tie things to the grid wherever that’s possible — and there close to 100,000 kilometers of electrified rail in the world, for example — and use batteries which are 80%+ efficient and very easy to charge from ubiquitous wires we already have in place. Use electric heat pumps and induction stove tops and electric arc furnaces for all the things we need heat from.
What this comes down to is that hydrogen isn’t fit for purpose directly for virtually any transportation form, to burn for heat of any quality, or for grid storage of electricity. Its inefficiencies and effectiveness challenges compared to electrification or biofuels mean that it’s unlikely to be used directly.
That’s okay, by the way, because we need green hydrogen for fertilizer and other chemical processes. But using it for heat, storage, or transportation makes no sense.
And here’s another source of confusion and contention. Green hydrogen is being deployed as a bait and switch for blue hydrogen. The fossil fuel industry is telling everyone who will listen, and politicians who are often happy to take their money, that if we just use black hydrogen for heating and transportation now, they’ll make it blue soon with a lot of taxpayer money, and then eventually we can have green hydrogen economy.
It’s a massive delaying tactic and governmental money grab by the fossil fuel industry.
Of course, there are the other people, the ones who read Rifkin’s Hydrogen Economy in 2000 or so, and never did the math. There are a lot of people heavily intellectually and fiscally invested in the hydrogen economy, and they spend a lot of time advocating for hydrogen pathways instead of direct electrification. The side that does electrolyzers have a good value proposition and should be listened to. The side that does fuel cells, not so much. They all want a piece of that $39 trillion, after all.
And there are countries and industrial giants that perversely love hydrogen for transportation, causing confusion. Some now very old men in Japan’s government and Toyota got together in the 1990s and decided that hydrogen was the answer, and 30 years later they have to die off before new blood can change to electrification without causing them to lose face. Germany’s chemical industry loves hydrogen, and they have salt caverns, and as a result they have a dream of dunkelflaute storage of hydrogen in the caverns, and the odd distinction of being the only country in the world where it’s possible to conveniently own and drive a hydrogen fuel cell car anywhere in the country because they have hydrogen stations all over the place. That filling network was naturally heavily subsidized by the German government, and is barely used. Hyundai has managed to capture some Korean governmental officials and is trying to recreate the Japanese debacle, as well as in smaller scale it’s national nuclear debacle.
Lots of fossil fuel money, investor’s money, and fan bois are spending a lot of time and energy promoting hydrogen for things it’s not useful for. And governments are getting sucked in by the massive fossil fuel lobbying effort, hence a bunch of the contention.
Finally, we have synthetic fuels. In the best case scenario, these fuels take CO2 from waste emissions and hydrogen from electrolysis of water and combine them into hydrocarbon fuels. It’s entirely chemically possible, and has been done, to make gasoline, diesel, and jet fuel.
Synthetic fuels have pretty much the same negative externalities as biofuels.
- CO2 (a lot less, but still present)
- nitrous oxide (N20) with a global warming potential 265x that of CO2
- nitrogen dioxide (NO2), which is a chemical precursor to smog
- particulate matter
- unburned hydrocarbons aka black carbon with global warming potentials thousands of times that of CO2, but typically less than bunker fuel
However, the kicker with synthetic fuels is that everything I wrote about the inefficiencies of hydrogen as a fuel apply doubly to synthetic fuels. After all the trouble of making it, compressing or chilling it, storing it, and possibly shipping it, then you have to use another lossy process to combine it with CO2 (which is also high energy to produce), and typically more processes to get it into a final usable form. By the time you get to the end of the process, the energy is like cocaine you buy from some guy on a street corner, stepped on so many times that you get barely any of the original substance.
What synthetic fuels have going for them is that they can be a bit cleaner than biofuels because there’s none of that messy biology and its convoluted organic chemicals in there, and like biofuels and fossil fuels, you can carry it in buckets, pipe it, and store it. The end result is effective, but deeply inefficient, and inefficiencies means that it will always be a lot more expensive.
But the final problem is when you use the synthetic fuel. Typically, they are burned, replacing gasoline, diesel, bunker fuel or kerosene in places where fossil fuels are used now. And that very expensive synthetic fuel’s remaining energy mostly turns into waste heat, with 15–20% efficiencies in cars, and better in bigger engines, but still below 50%. All that energy to make the synthetic fuels, and then you throw most of it away. This is just like fossil fuels, but since almost all the energy to make them was done millions of years ago by biological and geological processes, we haven’t cared. But when we make our own fuels from scratch, economics makes us care a lot.
Advocates of electrification point out that avoiding all of that hassle makes a lot more sense. Advocates of biofuels point out that biofuels are a lot cheaper, use a lot less energy to make, and have virtually the same advantages as synthetic fuels, and remember all the people advocating for biofuels.
Fossil fuel companies get in the mix too. They love synthetic fuels because they perpetuate things which burn fossil fuels, and they know that no one will ever pay for synthetic fuels when they can buy fossil fuels vastly more cheaply. Lots of baiting and switching, lots of ‘blended’ fuels with subsets of synthetic fuels mixed with fossil fuels, lots of lobbying.
This doesn’t mean we won’t make synthetic hydrocarbons, but they won’t be put in engines and burned for the most part. Power-to-X (P2X) will be for many industrial feedstocks, but power-to-fuel will be supplemental to biofuels.
So that’s the reason why there’s all this tribalism in alternative fuels. There’s a $39 trillion in annual profits in the industry up for grabs. The current players in the industry want to keep it all, and want to create as much confusion about alternatives as possible, and want to ensure that alternatives chosen can also use their products.
Other people, who actually want to solve the negative externalities problem and avert horrific outcomes from global warming, are fighting to be heard above the millions and billions of PR and lobbying.
In the end, the laws of thermodynamics will win. Hype doesn’t stand a chance against reality in the long term. But it’s an uphill battle, because the vast majority of people involved in the debate don’t understand or accept the laws of thermodynamics, but live on hope instead.
Here are some of my publications and podcasts where the subject is dissected in detail:
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