Nuclear power plant cooing towers
Quartette of cooling towers at unidentified nuclear power plant. Hydrogen needs to be created from other energy sources,which can include fossil fuels like coal, nuclear power or renewables, but cost will always be a keep factor. Current costs are estimated at 10 cents-a-mile for natural gas-reformed hydrogen.

Twenty Myths Challenged - Part III

Dr. John Wilson argues that we'll need to generate hydrogen from coal or nuclear power, if we go down the H2 pathway

By Dr. John Wilson

12 Since renewables are currently too costly, hydrogen would have to be made from fossil fuels or nuclear energy.

a) A hydrogen economy would require the construction of many new coal and nuclear power stations (or perhaps nuclear fusion stations).

We agree that nuclear energy in its present (essentially 50-year-old) implementation will be a high-cost option until alternative simpler SMR (small-to-medium reactor) designs now under development become available. But the biggest barrier to progress is the belief that has been instilled into the U.S. public by people like Dr. Lovins that nuclear energy is not safe. As the French have shown very clearly, it can be safe and can be depended upon to deliver highly reliable power. However, we think it very unlikely that any new facilities will be built in the United States for at least the next twenty years.

Conventional coal fired power-generating facilities also seem inappropriate since they are inherently "dirty" unless converted to clean-coal technology. However, coal + water -> hydrogen technologies are attractive since they can be operated with total carbon sequestration. They do, however, require water which is itself becoming a rare commodity in some parts of the U.S. West and Southwest.

b) A hydrogen economy would retard the adoption of renewable energy by competing for R and D budget, being misspent and taking away future markets.

Contrary to Dr. Lovins' views, we believe that a fossil-fuel (coal) hydrogen program, if it includes "zero emissions" coal-based hydrogen production, is just what Congress should be funding. As we have previously argued, natural gas as the near-term basis for major hydrogen production makes no sense whatever due to tight supplies whereas coal is in ample supply - the several hundred years of proven reserves should give us the time to find a sane alternative to gasoline or diesel fuel.

Lovins refers to "cheap" hydrogen storage. None of the options that he refers to are "cheap" by any measure. Nor, for the most part, are they readily available, despite the fact that there are real-world examples of underground storage that have been used for years. Not all underground formations are suitable for hydrogen storage, even if they did work well for coal gas at a time when a little selective hydrogen loss was considered acceptable because it slowly increased the BTU of the stored gas (rather like maturing a vintage wine!). Pipeline storage of hydrogen is clearly not applicable in Lovins' distributed-production model but would be (just as it is for natural gas) in the centralized-production case.

Regardless of the views of environmentalists, hydrogen in commercial quantities is clearly not going to be made from renewable energy sources for the foreseeable future. On the other hand, we believe that any initial steps that use natural gas to make transportation hydrogen would be a major misstep. The only route that makes sense is clean coal-to-hydrogen, coal-to-methanol-to-hydrogen or coal-to-syngas-to-hydrogen technology.

c) Switching from gasoline to hydrogen will worsen climate change unless we do a large amount of carbon sequestration.

We believe that it will be unfortunate if concern over carbon releases into the atmosphere drive the selection of, and the route to, hydrogen until we really understand the mechanism of global warming. While we are concerned about the ultimate disposition of man-made carbon emissions (e.g., in the oceans), especially as the world's carbon-absorbing plant resources are replaced by asphalt or unproductive farms, we do not subscribe to the often-made but seldom-evaluated claim that anthropogenic carbon emissions are the primary cause of global warming. There is strong evidence that a very modest upward trend in solar heating combined with major increases in atmosphere water vapor concentrations are the real culprits - and there is nothing that we can do about them. Global warming is something that we have to get used to.

d) Making hydrogen from natural gas would quickly deplete our natural gas reserves.

It would deplete our natural gas reserves - period. There is no way that our dwindling natural gas reserves should be used for hydrogen manufacture. It is true that the world (not the United States, Canada or Mexico) has some 200 years of estimated reserves at present rates of use but (1) those rates of use are increasing rapidly while new natural gas discoveries are not; (2) most of the reserves are NOT in the United States or countries contiguous with it but overseas in countries not especially friendly toward us - such as Saudi Arabia, Iraq, Iran and huge reserves in the former USSR. The U.S. currently imports very little natural gas (as LNG), although plans are being made to do bring in more from nearby Trinidad. However, by becoming dependent on imported liquefied natural gas to manufacture automobile fuels, the U.S. would simply become more dependent on foreign energy resources - not a good idea when the gas is mostly found in Islamic areas. Furthermore, LNG carriers, both on the high seas and in dock, are ideal targets for terrorists.

We will defer any discussion of Lovins' notions about how switching to natural gas would improve the use efficiency of the latter in some roundabout way. That result depends on actual fleet-average fuel cell efficiencies, market acceptance of fuel cell vehicles vs. other types, and the actual efficiencies achieved by (and acceptance of) competing alternatives. Any discussion at this time can only be hypothetical and probably misleading.

13 Incumbent industries (e.g., oil and car companies) actually oppose hydrogen as a competitive threat, so their hydrogen development efforts are mere window-dressing.

We substantially agree with Lovins that this statement is untrue, although many companies are involved in hydrogen research largely to keep a watch on progress and to maintain their place in any future line that might form. No one that we have spoken to in the conventional energy industry has so far been able to make a business case for becoming a hydrogen producer, but they all want to be ready in the event that hydrogen does "make it" commercially and in sufficient volume to interest them. Some scenarios call for them to act as a distributor and deliverer of merchant hydrogen bought from manufacturers such as Praxair and Air Liquide.

Unfortunately, Lovins then spoils his case by statements such as "hydrogen is a premium energy carrier" (not true by any measure - e.g., it takes too great a volume of hydrogen to carry too little energy) and by implying that the oil industry is interested because hydrogen will be manufactured from "more profitable" natural gas. It will not if no gas is available. Neither is hydrogen anywhere close to being manufactured from renewable energy sources in anything like sufficient amounts. We have already discussed the concept of making hydrogen close to the customer (a very high-risk concept) and, since the economics of doing so depend closely on the number of units that can be made, all hydrogen cost projections must be considered suspect. At this stage in the development of any new industry, economic discussions that project pricing with apparent high precision must be considered very suspect. Nevertheless, there is no doubt that any commodity that can be used efficiently is more attractive than one that is not.

Finally, we agree with Lovins on the future of hydrogen from coal - if a sufficiently large market develops for hydrogen (which, as we have said, we doubt). The only concern is that water will have to be the source of most of the hydrogen and water, like natural gas, is a commodity in increasingly short supply.

14 A large-scale hydrogen economy would harm the earth's climate, water balance or atmospheric chemistry

We agree with Dr. Lovins' conclusions in this segment, although we prefer an alternative interpretation of the influence of water vapor. We have long regarded the relatively rapid run up in atmospheric water vapor levels as the primary global warming agent with modestly rising anthropogenic CO2 levels a secondary and not very important effect, albeit one that is magnified by water. Recent data, including that of Held and Soden (Lovins, Ref. # 129) can be interpreted as supporting this view. We wholeheartedly endorse Lovins' view that this issue "must be carefully evaluated" before we proceed with any major shift in the energy system, but at present, it is far from clear that removal of current or future CO2 from the atmosphere will have any beneficial impact on global warming.

a. Using hydrogen would release or consume too much water

Release of combustion water is a non-issue since it will (given time) simply compensate for the water used in manufacturing the hydrogen and/or will equilibrate with global oceans and wetlands. In any case, there are so many large sources of water vapor emissions that the contribution made by either gasoline or hydrogen vehicles is relatively small. While water vapor is a key contributor to global warming, it does not appear that combustion water is a significant factor.

Consumption of water is another matter. Considerable amounts of water (for electrolysis) or steam (for reforming) are used in manufacturing hydrogen because water supplies at least half of the hydrogen produced by the reforming process. In some areas, this added demand for water could be a major concern. However, use of desalinated water or even recycled and treated industrial process water might be suitable - and necessary - in some cases to avoid aquifer depletion of curtailment of domestic supplies.

b. Using hydrogen would consume too much oxygen.

We agree with Lovins - it would not.

c. Using hydrogen would dry out the Earth by leaking hydrogen to outer space.

No comment is justified.

d. Using hydrogen would harm the ozone layer or the climate by leaking too much water-forming and chemically reactive molecular hydrogen into the upper atmosphere.

We agree almost entirely with Lovins that this claim, which persists in the popular media, is unfounded, although we do not support Lovins' repeated claims that all things good and wonderful should be credited to a hypothetical hydrogen economy (when we actually have one we will be better able to judge that). Hydrogen does leak from industrial equipment and is or was released by a few industrial processes, but is apparently quickly oxidized in the atmosphere, presumably by reaction with OH- radicals. Former coal gas operations leaked large amounts of hydrogen for many years (as did the many chlor-alkali installations in this country and elsewhere), but no ozone layer damage has ever been attributed to this.

Contrary to Lovins' statement that papers raising concerns such as these set back the cause of the hydrogen economy, we view them, however wrong they may be, as stimulating essential and long-overdue debate on the hydrogen economy and providing much-needed checks and balances on the "rush to judgment" that has characterized the entire hydrogen effort to date.

Series concluded next week...

Times Article Viewed: 5562
Published: 25-Oct-2003


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