Just under a year ago, I told a nuclear industry gathering that the industry needs to get real about the atom’s role in the Hydrogen Economy. Because it is a huge source of cheap zero-carbon energy, nuclear has great potential to produce enormous amounts of hydrogen from water. This could revolutionize the energy and transportation sectors—but not in the way many nuclear industry proponents think. Too often, industry proponents drink the heady fuel-cell wine. In my opinion, there are better wines. There’s also outright sobriety, which is never a bad thing. (To see the whole speech, click here.)
So what did I mean by “get real”? Briefly:
- Stop talking about fuel cell- or pure hydrogen-powered cars. For excellent reasons, nobody believes they will be mass produced any time soon. For details about why, see part B of my speech; it starts on page 9.
- Talking about fuel cell- or pure hydrogen-powered cars will hurt your credibility with those who hold the purse strings. They no longer believe the hype, and have scaled back funding for fuel cells.
- If nuclear hydrogen proponents keep talking about fuel cells, that could jeopardize funding for nuclear hydrogen.
- This doesn’t mean stop thinking about the hydrogen highway. Instead, think of more practical ways to make it happen.
Now, the main obstacle to a transportation economy based on pure hydrogen as a fuel is hydrogen storage. To put enough hydrogen on board a standard-size car to give that car a range that is comparable with that of a gasoline-powered car, you’d have to make the fuel tank the size of the car—the energy density by volume of hydrogen is much lower than that of gasoline.
Researchers have been trying to solve that problem by developing ways to store enough hydrogen to overcome its energy density shortcomings and make it practical as a pure fuel on a standard-size car. The problem with that, according to the American Physical Society in 2004, is that major scientific breakthroughs are required for that to happen. And that is because
… no material exists to construct a hydrogen fuel tank that meets the customer benchmarks. A new material must be developed. —American Physical Society, 2004
So keeping that in mind, what did I mean when I said nuclear hydrogen proponents should think of practical ways to make the hydrogen economy happen?
First, we don’t have to invent a new material to store hydrogen. We already know a material that stores it quite well: carbon. When carbon is bonded with hydrogen at the molecular level, in various configurations, the result is liquid hydrocarbon fuels, like gasoline and diesel.
And we already know how to combine hydrogen with carbon to make these fuels. This is via the Fischer Tropsch (FT) synthesis, which was invented in the 1920s and perfected since then.
The raw material for FT is synthesis gas (syngas), a mixture of hydrogen and carbon monoxide. Syngas is a raw material for numerous other valuable chemicals, including methanol and of course FT products.
Where would carbon monoxide (CO) come from? CO can be manufactured using carbon dioxide (CO2) and hydrogen as raw materials. Such a process is endothermic, meaning it requires heat. If these materials are reacted at high temperature, conversion to CO is higher.
If that CO2 were to be captured from the exhaust gases at coal-fired power plants (which are the biggest sources of man-made CO2), then suddenly we see a way to make not just nuclear hydrogen viable, but also carbon-capture schemes.
You can see how central nuclear heat and hydrogen would be in the “C1 Economy.” (C1 chemistry refers to the use of single-carbon molecules—like carbon monoxide and dioxide, as well as methane—to produce chemical building blocks for other chemical products and hydrocarbon fuels.)
Shifting focus from a Hydrogen Economy based on hydrogen as a pure fuel to the C1 Economy based on water-derived hydrogen as a raw material for cleaner hydrocarbons gives nuclear hydrogen a much-needed boost of credibility.
I am happy to see that in the year since I gave that speech there has indeed been a major focus-shift in the U.S. hydrogen R&D community. Look at the website for the Next Generation Nuclear Plant; the focus is now on chemical manufacturing—using nuclear heat and hydrogen for making fertilizer and plastics, and refining conventional fuel. This reflects the actual needs of the industry partners, which include major chemical companies like ConocoPhillips, Dow Chemical, Potash Corp., and Eastman Chemical.
I gave the speech at the Sheraton Hotel in Saskatoon, Saskatchewan. The Sheraton is about a three-minute drive from the Canadian headquarters of Potash Corp., one of the NGNP industry partners. Coincidence? Probably. But at least great minds think alike!
I recently participated in a very interesting conference call with Finis Southworth, who is Areva North America’s Chief Technology Officer. Areva is one of the nuclear companies involved in NGNP, and has been developing the Antares, a high temperature gas-cooled reactor with an outlet temperature in the 850 to 1000 C range. Such temperature would be ideal to react CO2 with hydrogen to make CO.
Steve – it sounds like you would enjoy talking with Bonne Posma of Liquid Coal. You can find his web site at http://www.liquidcoal.com.
He spent quite a bit of time working at Sasol and now runs a company that provides electric traction sleds to the underground coal industry. He is on board with using nuclear heat as the way to produce the required hydrogen to significantly upgrade coal and heavy oil.
Rod — I have always wondered when Sasol and PBMR would hook up. The PBMR’s outlet temperature is right in the sweet zone for splitting CO2 into CO, and possibly for efficiently splitting the H out of water as well. And of course Sasol has plenty of expertise and experience turning syngas into liquid fuels and other products. PBMR shifted its focus from power generation to process heat a bit too late to save itself from the government axe, but who knows, it could be resurrected if somebody comes forward with a credible plan for making money.
Liquid Coal and other coal-to-liquids outfits could be in line for serious funding if petroleum prices keep going up.
Of course gas companies are also thinking exactly the same thing — in fact Sasol also has gas-to-liquids operations in Qatar and Nigeria.
I favour the indirect route to coal liquefaction, i.e. burn it to make electricity but recycle the CO2 into liquid fuels or other chemical products. We would need major amounts of hydrogen for that, needless to say.
If I’ve been reading the papers correctly, coal can be reacted with supercritical water at considerably lower temperatures than that. It makes little sense to burn coal and then reclaim the CO2 when you can use it (or biomass) directly.
If the only money maker were the products of coal gasification by supercritical water, then I agree it makes little sense to burn it first.
But burning it first carries a big financial advantage if you’re a utility that sells coal-fired electricity.
So the question is, could the selling price of captured CO2 be high enough to make it worth the utility’s while to capture it (i.e., overcome the efficiency penalty inherent in CO2 capture) and low enough for it to be profitable to sell chemicals made from CO2.
Electricity is fungible; it doesn’t matter what you’re generating it from, electrons are all the same.
Efficiency does matter. If you need a 2 GWe nuclear plant to reclaim the carbon output of a 1 GWe coal plant, you might as well not bother with the coal plant. That’s the reason why the Green Freedom scheme is defective by design.
I think that’s the wrong question. The right question is, what’s the minimum-cost pathway to go from X amount of carbon in coal plus a bunch of fissionables to X amount of carbon in motor fuel plus a bunch of electricity? I very strongly doubt that the best option involves burning coal in air.
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I’ve feeling out of my depth here but way back in the 1970’s with the oil scare and they were looking into alternatnative fuels, there was talk — and a feasibility study was done — of harvesting or mining for deuterium. I know the isotope, referred by some as heavy water, can be used for generating weapons-grade material, but the engineering study highlighted that deuterium at room temperature electrolyses naturally into regular H2. I’m not qualified to know if that is true or not.
I thought that if we are to have a long lasting Hydrogen Economy, one factor would be the costs associated in getting hydrogen into the industrial-consumer framework. If we convert direct the deuterium to H2, or synthesize directly into carbon-deuterium or a carbon-hydrogen liquid fuel mix, at next-to-nothing costs, then we can do away with the hype and focus on how to transfer that cost-cut into the hands where it matters the most — your average consumer.
The problem now is getting to the deuterium. If I recall rightly the proponents were saying that there is a rich field or deposit of deuterium but unconfirmed roughly about 800 miles long, 50 miles at widest point, and 3 miles at deepest point — here’s the real kicker — located off the Philippine Trench under 7,000 meters of water and at over 10,000 psi.
Now I’m wondering if there is any basis for the indicated deuterium presence because the proponents had spoken of the high pressures stripping the seawater of its oxygen component resulting in the hydrogen isotope. And is there anyone in the industry currently investigating this line of inquiry.
[…] will come with the advent of hydrocarbon fuels made from recycled CO2. As I mentioned in “Game-changing nuclear moves in the US,” carbon is about the closest anything has ever come to being a perfect storage material for […]