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.