A Response to
How utilities can save America from its oil addiction
James Hopf
7.31.04
I agree wholeheartedly with this article. I used to be an enthusiast for the hydrogen economy (with the concept of using a high-temperature reactor for thermo-chemical hydrogen production being particularly intruiging). Then I got involved in a long message board discussion on the hydrogen economy on the John Kerry website. There were several posters who were quite knowledgeable on the subject, and who made solid rational arguments. To make a long story short, the position that the H2 economy is not the way to go clearly won the day, and even I was convinced.
In addition to requiring nothing less than a whole new transportation fuel infrastructure, the hydrogen approach is very inefficient. After converting electric energy back and forth from H2, you wind up with only ~40% of the energy you started with (due to electrolysis and fuel cell efficiencies). This calculation does not even include additional losses associated with compression, handling, and moving the hydrogen around, etc.... In addition, there are the enormous expenses involved with developing a completely new infrastructure to distribute gasous fuel (a system that is fraught with serious technical challenges, due to the difficulty in containing H2, as well as the much larger energy required for compression). And finally, there is the costs of the additional equipment such as electrolysis equipment and fuel cells, both of which remain extremely expensive. The cost of electrolysis equipment if sufficient to effectively add multiple cents to the cost of the electric power. And vehicle fuel cells still cost ~1 million dollars, I've heard.
By contrast, using alternative liquid fuels such as methanol (or biodiesel) involves little change to our existing infrastructure OR our car technology. These fuels can be used with very minor, if any, changes in standard car technology (or retrofits to existing vehicles). There are few technical challenges. Combining this with the efficiencies associated with CURRENT hybrid technology will reduce fuel usage and emissions to very low levels, all the while using purely domestic fuels.
And, as the article states, we will be able to make a very large leap forward from there, using evolutionary technologies that are just around the corner (as opposed to using revolutionary hydrogen/fuel cell technologies that are much further out). I refer specifically to the plug-in hybrid car concept. This is the approach I came out of the Kerry site discussion favoring, as opposed to the H2 economy. We should instead rely on alternative, domestic, liquid fuels (e.g., methanol or biodiesel), or plug-in hybrid cars, or (better yet) some combination of the two. Me and the author of this article seem to agree on this.
With the advent of hybrid cars, automakers are now mass producing batteries that are much more powerful (and must meet much greater demands) than the old standard 12-volt lead acid battery. They are also investing large amounts in new battery technologies. Due to these developments, I'm hearing that batteries that can power a reasonably sized car, with reasonable performance (unlike the old pure electric cars) with a range of ~20-50 miles are just around the corner. This is still not enough to make pure electrics attractive, as people still demand the convenience of driving longer distances occasionally, without having to "make arrangements". However, with the plug-in hybrid car, this is not an issue. A tiny IC engine (or diesel) engine is there, and will just fire up whenever the battery range is exceeded.
As the author states, based on most people's driving habits (with daily commutes generally under 20-50 miles), this will allow most of our mileage to be powered by domestically produced electricity. These cars will also be zero emissions most of the time, especially in the cities, where emissions are most important. Even out in the country, when the small engine might be used, emissions will still be a small fraction of those of a typical new car today. This emissions performance will be "good enough", with few premature deaths arising from auto emissions. Also, due to both the high efficiency of this hybrid vehicle in the first place, and the fact that electric power is primarily used, overall fuel consumption will be a very small fraction of what it is today (~25% or less). This will also be "good enough", in terms of fuel use, especially given that most or all of the (liquid) fuel can be produced with domestic sources, as the article explains.
Not only will domestically produced electric power be used for most of the vehicle miles, but this energy source will be much cleaner, on balance, than burning oil in cars. This will clearly be true if the new baseload plants that are built to fill this new off-peak demand are based on nuclear, clean coal (IGCC), or renewable technology. Another benefit, as compared to the H2 economy approach, is that this electric power will be use
is that this electric power will be used MUCH more efficiently. For most of the vehicle miles, these plug-in hybrids act like true electrics, with respect to efficiency. Electric power is shipped directly to the car battery, and then to the electric motors, with an overall efficiency of ~80-90% (i.e., ~80-90% of the generated power makes it to the electric motors). This is more than double the efficiency of the H2 approach (~40%). Thus, the amount of new power plants that would need to be built is only about half the number necessary using the H2 approach.
And finally, this approach requires no new expensive infrastructure or technology. The power is simply shipped over our existing power grid (which can handle the extra load during off-peak hours). We also don't need exotic (and expensive) fuel cells, but instead just some minor changes/advances over the hybrid cars alreay in use today. There will also be less adjustments for the consumer to make, who simply needs to plug in the car at night, and occasionally go to the "gas" station and fill up with liquid fuel just like always. Gasous fuel fueling seems like it may be a difficult, complicated process that will require adjustments on the part of the driver.
I also aprreciated the fact that the article did not discuss ethanol from corn, but instead discussed more plausible large scale sources of methanol (although I'm generally not a fan of coal). The corn/ethanol concept strikes me as an inefficient process that is more of a sop to (politically powerful) large-scale farmers than anything else. I even hear this approach may take more petroleum than it dispaces (i.e., a negative EROEI - energy returned on energy invested). Other options, such as other crops, or (better yet) biodiesel have much better EROEI values, may use much less fertilizer and pesticide, etc..., and require less alterations to the engine.
One disappointment with the article is that it did not discuss biodiesel. I hear that this is available right now (for ~$3/gallon), and that it can be used in existing diesel cars (which get better mileage in the first place) without any modifications! This fuel, biodiesel, was the one that seemed to win the day in the Kerry site discussion. It has a very good EROEI, it requires the least adjustments to current technology, and it has the best hope of being economically competative. Also, unlike the coal/methanol idea, it is renewable and (supposedly) CO2 neutral. In the future, we may even be able to use algaes to produce this stuff, with no pesticides, etc..., and a relatively low land area required to produce a given amount of energy. My personal favorite technology is a plug-in hybrid car with a TINY (~1L?) diesel engine that uses biodiesel for the occassional long trip where the battery range is exceeded.
In summary, the domestic liquid fuel and/or plug-in hybrid car approach can deliver almost all of the benefits of the H2 economy at a tiny fraction of the cost, and can be deployed over a much shorter time frame. It is also much more incremental, requireing few changes to our existing technology and infrastructure, sparing the nation from having to undergo radical transformation. The point here is the old wisdom of not letting dogged persuit of the perfect getting in the way of the VERY good (or more to the point, the good enough). The above technology is defintely the next wave, with the H2 economy PERHAPS being the wave after that (in the much more distant future, say after ~2030 or even 2050). The above approach is so good, however, we may have little incentive to go through the huge cost of making the transition to the H2 economy. My gut tells me that after we use plug-in hybrids for a few decades, pure electric cars will be ready. Keep in mind that, if you have a sufficient battery, pure electric cars are clearly superior to hydrogen powered cars, due to the much greater energy (well-to-wheel) efficiency of the approach (i.e., ~80-90% vs. ~40%).
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