Technological Change And Hydrogen By Electrolysis

Lynne Kiesling

Yesterday the New York Times had an article on a new method of producing hydrogen from electrolysis using nuclear power (registration required). The new technique still is not a net production of energy, but it has drastically cut the amount of energy required to isolate the hydrogen:

The heart of the plan is an improvement on the most convenient way to make hydrogen, which is to run electric current through water, splitting the H2O molecule into hydrogen and oxygen. This process, called electrolysis, now has a drawback: if the electricity comes from coal, which is the biggest source of power in this country, then the energy value of the ingredients – the amount of energy given off when the fuel is burned – is three and a half to four times larger than the energy value of the product. Also, carbon dioxide and nitrogen oxide emissions increase when the additional coal is burned.

Hydrogen can also be made by mixing steam with natural gas and breaking apart both molecules, but the price of natural gas is rising rapidly.

The new method involves running electricity through water that has a very high temperature. As the water molecule breaks up, a ceramic sieve separates the oxygen from the hydrogen. The resulting hydrogen has about half the energy value of the energy put into the process, the developers say. Such losses may be acceptable, or even desirable, because hydrogen for a nuclear reactor can be substituted for oil, which is imported and expensive, and because the basic fuel, uranium, is plentiful.

The idea is to build a reactor that would heat the cooling medium in the nuclear core, in this case helium gas, to about 1,000 degrees Celsius, or more than 1,800 degrees Fahrenheit. The existing generation of reactors, used exclusively for electric generation, use water for cooling and heat it to only about 300 degrees Celsius.

The hot gas would be used two ways. It would spin a turbine to make electricity, which could be run through the water being separated. And it would heat that water, to 800 degrees Celsius. But if electricity demand on the power grid ran extremely high, the hydrogen production could easily be shut down for a few hours, and all of the energy could be converted to electricity, designers say.

The kicker here is, of course, building the type of nuclear reactor that would be able to serve such double duty. Perhaps if natural gas prices stay close to $7/mmBTU and oil stays above $40/barrel we’ll see the construction of new nuclear reactors.

Very interesting development.


9 thoughts on “Technological Change And Hydrogen By Electrolysis

  1. Prof. Kiesling…You are correct that this is an interesting development but Mr. Wald exaggerates somewhat in terms of its novel;ty. High temperature electrolysis has long been recognized as the likely next stage of H2 production using emission-free nuclear power. Nonetheless, it is an evolutionary step. Todya, the nation’s fleet of 103 reactors could be producing H2 with off-the-shelf electrolysis technology. And whil;e Mr. Wald is correct that some of the energy value is lost, the price of producing electricity from nuclear plants is so low that it merits serious consideration.

    Two factors are important. Getting the nuclear industry familar with the process of producing, storing, delivering and dispensing H2 will be a critical first step toward development of H2 infrastructure. This in turn, combined with low electricity production costs lower the price of the pure H2 needed for fuel cell R&D. Currently the major industrial gas companies hold something of a stranglehold on H2 price that has a stultifying effect on innovative fuel cell development.

    By the time high temperature electrolysis is practical–materials issue loom large at such high temperatures–the nuclear industry and the nation will be better prepared to deal with the challenges of a possible transition to an H2 economy. Then, the even more efficient thermo-chemical H2 cycle will prevail.

    Mr. Wald is also correct that there is a problem producing H2 with fossil fuels in that the primary benefit of an emission free energy carrier is vitiated unless emissions are captured and contained. Increasingly, it is becoming evident that we will need H2 from all sources if a real transition is to occur.

    Richard N. Smith
    Director, Policy Analysis
    Nuclear Energy Institute

  2. This may be an interesting development; however, I doubt it.

    Notwithstanding that the newspaper report (I read copy from Indianapolis Star, not NYT original) is very thin on details, and typical of attempts by newspapers to report on scientific issues, there are a number of significant immediate problems:

    1) The Star report says the heart of the plan is “an improvement on the most efficient way to extract hydrogen; you report it is “an improvement on the most convenient way to make hydrogen. Both of these are very much subject to debate on a number of considerations, not to mention various extrapolations/forecasts of relative prices.

    2) This is hardly a “breakthrough in producing pure hydrogen”. In fact, the correct term for this process is “direct water dissociation”, and is a well-understood scientific process. It has been achieved successfully via a number of methods, including concentration of solar radiant energy by a parabolic mirror see DIRECT SOLAR-THERMAL HYDROGEN PRODUCTION FROM WATER

    3) As you admit, the most obvious impediment to ever realizing “real-world” hydrogen production is the word “nuclear”. While a serious discussion is well beyond this forum and very difficult to even achieve, my personal viewpoint is that this is because nuclear really does present truly serious problems.

    Noteworthy is that the proposal again presupposes that a prerequisite and necessary sustaining feature of the “hydrogen economy” is a form of centralized, mass-volume production facilities, thus necessitating a means of shipping and storage.

    This is consistent with the DOE vision. Unfortunately, this represents a failure to recognize the very nature of hydrogen, and how it differs from our traditional energy carriers. Which I emphasize because your opening paragraph contains the statement “The new technique still is not a net production of energy”. Which it cannot be, because hydrogen (like gasoline and electricity) is not an energy source, like oil, coal, natural gas, wind, or solar — it is only an energy carrier.

    I did not find any reference in the Star article to correlate to your statement “Hydrogen can also be made by mixing steam with natural gas and breaking apart both molecules, but the price of natural gas is rising rapidly”. I hope this is not your conclusion, but from the NYT, as this is a totally unwarranted dismissal of the method generally-acknowledged by non-DOE personnel and researchers to be both:

    1) the best solution to achieving a short-term end to reliance on petroleum, and

    2) the key to transitioning to a “hydrogen economy”

  3. Some concerns for your consideration.
    1. It is highly unlikely that any new nuclear power plants will be built in the US until the regulatory agencies develop and commit to a dramatically streamlined review, approval and construction process, since it was regulatory changes and plant redesign during construction which resulted in massive capitalization of interest on construction work in progress and, thus, massive increases in plant investment.
    2. New plants will likely be required to be located offshore, where unlimited access to cooling and process water is available, since the available supply of fresh water for human and agricultural consumption is under extreme pressure in growing areas of the country. This pressure will increase in the future, as the US population doubles by 2050 and doubles again by 2100.
    3. These new plants would also be capable of producing potable water, which will be a growing need as population increases.
    4. Offshore location of these plants would radically simplify the development of evacuation plans, which were the after-the-fact downfall of the Shoreham plant on Long Island.
    5. Offshore location of these plants would require the installation of anti-submarine warfare and anti-ballistic missile systems to protect the plants from military or terrorist attack.
    6. Nuclear fuel reprocessing and spent fuel storage issues must be addressed and resolved if nuclear energy is to replace petroleum-based fuels in the US transportation market, as well as to meet a significant portion of the growth in electricity demand and consumption.
    7. The financial risks associated with nuclear power plant construction and operation were substantially reassigned by the availability of utility ratebase treatment for the investments. It is highly unlikely that private capital will be anxious to pursue new nuclear plant investment without some assurance of the ability to recover the investment.

    The revival of the nuclear power industry in the US, no matter how essential, will be a long and difficult process.

  4. Until all of the environmentalists in the country gets a clue transplant, we’ll not see a new nuclear power plant build in this country anytime soon.

  5. One nit:  The simplest and most efficient method of producing hydrogen from coal does not involve electrolysis; it involves gasification with oxygen (not air), cleanup of the syngas and shift-conversion of carbon monoxide to hydrogen.

    Cold-gas efficiencies of high-temperature gasifiers run around 75% or so, and produce a syngas which is around 37% H2 and 73% CO after cleaning and CO2 removal.  You can calculate the energy loss in the conversion of the remaining CO to H2 (CO + H2O -> CO2 + H2).

  6. Check out Don Lancaster’s website — Tinaja.com

    He has been around for quite a while and has written a bunch of info (PDF format) on all sorts of alternative energy stuff:

    Home Page
    http://www.tinaja.com

    What’s New (check the entry for Nov. 27 quoted here):
    http://www.tinaja.com/whtnu04.asp

    There are several SAE and IJHE papers that suggest that a modest (perhaps 5%) hydrogen injection into a conventional gas or diesel engine significantly improves both mileage and emissions. But it has yet to be shown whether any net gain can economically result. And whether such injection can be made compatible with ongoing vehicle improvements.

    The most likely route would be fuel reformation driven by heat from the exhaust stream. I’ve had several people wanting to use electrolysis instead contact me who clearly have not even begun to look at the fundamental numbers. Which appear really, really grim to me.

    Fer instance, an 18 wheeler might want to do a 5% injection into a 300 Horsepower engine, or 15 net horsepower of hydrogen.

    Water is one ninth hydrogen. At five percent injection, the water tank alone would have to be 9/20ths the fuel tank size and thus not a minor consideration.

    15 horsepower of hydrogen would be 11,190 watts. Or, over an hour, 11,190 watthours. Electrolyzed water produces 3 watt hours per liter, so 3730 liters per hour or 62 liters of hydrogen per minute would be required. With the finest of platinized platinum electrodes, electrolysis could possibly approach 50% efficiency before amortization.

    Cheaper electrodes (such as an abysmally poor choice of stainless steel) would likely leave efficiency down in the 25% range.

    And most auto alternators aren’t all that efficient, so something like 60 horsepower at the belt might be needed. A trucker might not be totally overjoyed at taking a one-fifth hit on fuel costs and available power. Further, at 12 volts, 60 horsepower would require a 3730 amp alternator, considerably larger than anything commercially available for the automotive market. Further, a typical V-belt is rated around five horsepower, so TWELVE belts might be needed between the engine and the alternator!

    Sorry for the long quote…

    Two other links are here:

    Energy Fundamentals:
    http://www.tinaja.com/glib/energfun.pdf

    Electrolysis Fundamentals:
    http://www.tinaja.com/glib/muse153.pdf

  7. Lynne: The problem is political not technological. Right now nuclear power is DoA in the USA even if France derives 70% of it electricity from nukes and reprocesses fuel rods. Rational argument probably won’t help. You can not rationally argue a man out of a position that he was not rationally argued into in the first place.

    Second point. I do not believe in Hydrogen. The cost of manufacturing, storing, transporting and using it is excessive in comparrison to the minor gains (mostly in some forms of air pollution reduction, but not all) from using it. However, the technology is far from useless. I note the following paragraphs from the NYTimes article:

    “Another problem is that the United States has no infrastructure for shipping large volumes of hydrogen. Currently, most hydrogen is produced at the point where it is used, mostly in oil refineries. Hydrogen is used to draw the sulfur out of crude oil, and to break up hydrocarbon molecules that are too big for use in liquid fuel, and change the carbon-hydrogen ratio to one more favorable for vehicle fuel.

    “Mr. Herring suggested another use, however: recovering usable fuel from the Athabasca Tar Sands in Alberta, Canada. The reserves there may hold the largest oil deposits in the world, but extracting them and converting them into a gasoline substitute requires copious amounts of steam and hydrogen, both products of the reactor.”

    There are also oil shales in Wyoming, lignite deposits in the Dakotas and high sulf coal in the Appalachins that could be processed into high quality fuel with this type of technology.

    But, the real problem is political.

  8. This new/old? system of producing hydrogen is very interesting. The comments others have made reafirms my own research and ideas about hydrogen being an energy conduit. There is another aspect of using hydrogen as a fuel. There is admitedly lots of btu per pound in hydrogen but it takes a lot of space, 3 times that of gasoline…… or it takes about 3 gallons of liquid hydrogen to equal the btu content in one gallon of gasoline. That is liquid hydrogen. That is a big tank on/behind your car….or a gas station on every corner.

  9. I saw this article as well and I see it as nothing more that the nuclear industry jumping on the ‘perceived’ green hydrogen economy as a way of becoming legitimate again.
    I have a proposal to electolyse hydrogen either directly with solar hydrogen cells or by conventional electrolysis and then convert it to methane. The CO2 comes from the air and is gathered by a modified Solar Tower. I have detailed my idead and you can see them at http://www.evworld.com/view.cfm?section=article&storyid=781

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