Also in theory, replacement of the current gasoline-powered vehicle fleet with "pluggable hybrids" could reduce gasoline consumption by 70%-80%. Of course, this depends on whether the next generation of battery technology proves workable and economic, and whether the electrical grid and generating capacity is beefed up sufficiently. But this potential new demand on the electrical system is problematic, to say the least. If current trends continue, most of this new electrical demand would be met from increased coal consumption, and overall greenhouse gases could increase as vehicle miles traveled (VMT) continued to soar. ON the other hand, one would think the first priority for installation of new wind and solar capacity would be to reduce EXISTING fossil fuel usage.

While there has been much discussion of electrifying automotive transportation such as pluggable hybrids, electric cars, and so forth, discussion of electrifying the rest of ground transportation seems to have gone missing in action. For example, my preliminary estimates show that investment of less than $100 billion (about 2/3 of one year’s U.S. spending on highways, streets and roads) is needed to electrify railroad mainlines. This would reduce fuel usage by the railroad industry, reducing overall ground transportation fuel usage by up to 1.5% annually (e.g., 3 billion gallons). Indirectly, up to 10% of transportation fuel usage may be saved, mainly due to vastly improved freight railroad performance and new railroad express freight options facilitated by the higher speeds of electrified services (raising average freight railroad speeds from less than 30 mph to 40-60 mph requires electrification to be practical). On the passenger side, another 2-3 billion gallons per year could be saved by a revival of intercity passenger rail service (though additional investments would be needed on the order of $50-$100 billion, not including totally new high speed rail lines).

In terms of urban passenger transportation, the greatest fuel savings and reduced carbon emissions will come from changes in land use, particularly where walking and bicycling are practical options. In the relatively rare U.S. cases where land use currently allows, short pedestrian trips are functionally equivalent to "non-home based" and many "chained" trips recorded by automobile. An example would be NYC subway riders or BART users who walk to the dry cleaners, bank, hardware store, etc., as part of their daily routine. In the auto-dependent suburbs, one DRIVES between these various business functions, dramatically increasing overall VMT.

The implicit assumption of traffic engineers and auto apologists is
"all passenger miles are equal." But much closer to reality is "all
TRIPS, of whatever type, are equal for the particular individual
involved." If it is possible for someone to walk to work for the job
he/she prefers, that walk trip is equivalent to an hour each way to the
same job by automobile. If someone takes transit to work in a mixed use
area and can make a number of short walking trips for various reasons
(to the bank, dry cleaners, florist, pharmacy, etc.), then those short
walking trips are of the same value, and are "functionally equivalent"
to much longer trips for the same purposes by automobile to dispersed
locations. Residents of places like San Francisco or Manhattan are no
less "mobile" as a practical matter, even though they drive far less
per capita, and walk and take transit over much shorter distances at
much higher rates than residents of the same incomes who live in
dispersed low density suburbs.

A key function of transit, particularly rail transit, but often overlooked, is to connect and maintain these islands of walkability. Research funded by the American Public Transit Association (APTA) indicates direct fuel savings of around 0.25 to 0.30 gallons per transit trip. But other research (see, for example, http://www.nrdc.org/media/pressreleases/020610.asp) indicates that, for every passenger mile on transit, several passenger miles by automobile are suppressed. Thus, if sufficient investment is made designed to triple annual transit usage (e.g., adding another 100 billion annual passenger miles by transit in the U.S.), several hundred billion passenger miles by automobile would be suppressed or precluded. This of course assumes parallel improvements in urban walkability.

Social Scientist: Freepublictransit.org says, "If public transit were free, more people would use it. Fewer auto miles would be driven." Of course, but to what extent? Do you have any data you can share on the extent to which transit ridership has increased when its price was lowered? I’m working on a study of this in NYC and would welcome any hard info. Thanks.

…need judicious and creative incentives and regulations in addition to a carbon tax, ….

here is one: http://www.freepublictransit.org
low-tech – politically viable – immediate results – strong anti-sprawl medicine

Of course, even if the market response is rapid, it changes the average fuel efficiency of the fleet only slowly � which is one reason why the short-run price elasticity is so much smaller than the long-run. But global climate change is a quintessential long-run problem, so it is the size of the ultimate response, not its timing, that matters.

Charles is exactly right that a carbon tax would extract greater percentage savings from electricity than from transportation. To Sperling, this apparently is a weakness. He is a transportation specialist, and he is determined to make big gains in the transportation sector. But actually the imbalanced reductions coming from a carbon tax are just the right approach. The lower price-elasticity in the transportation sector reflects real costs of change. Undertaking some such costs is necessary, and I applaud Sperling and many others for research showing how it can be done. But there is no reason to beat ourselves up more than necessary if there are cheaper ways to achieve the same greenhouse gas reductions � which is exactly the case for coal-fired power generating plants.

I don�t know whether a low-carbon fuels standard is a better approach to greenhouse gas reductions in transportation than other measures available. What I do know is that low-carbon fuels would be strongly encouraged by a carbon tax. So would a lot of other helpful responses, some well understood and others perhaps undreamed of.

Let me mention that the study at UC-Irvine that Charles refers to is co-authored by Kurt Van Dender. Also, lest anyone get the wrong impression, I am active in UC-Irvine�s Institute of Transportation Studies but I am not its director.

Thanks for writing. It’s tempting to say that we need a hundred or a thousand more Lorna Salzmans to keep pressing our points. (After all, it was you who rekindled my dormant interest in carbon taxes in 2003 through your interest and passion.) You’re spot-on that our existing institutions including the environmental movement are falling down on the job, particularly with their inane focus on 2050 — a date so distant as to be meaningless institutionally as well as for climate-safeguarding.

The Carbon Tax Center will continue doing its best to frame, clarify and advance the points you’re making. I hope others will have further suggestions for opening up space within the institutional gridlock.

  — Charles

But I do not see, at this point, any of the leading environmental groups, much less any one in congress, with draft legislation that incorporates ANY of these things! All we have seen so far is legislation to mandate higher vehicle standards by 2020, and, finally, some scepticism about the pointless counteproductive subsidies to corn-based ethanol. Coal industry demands for subsidies for converting coal to liquid fuels have not yet been fulfilled and doubts have been raised about it, luckily, but coal state industries and legislators die hard. In any case, these other urgent policies have yet to be incorporated into legislation.

This means that congress and the environmental movement are falling down on the job. In addition, the use of the year 2050 by which we should have reduced CO2 concentrations by 80% is at least thirty years later than the date that all credible scientists and studies say we should have reached that goal. All of this together is frustrating and depressing, especially given the dedication of the Carbon Tax Center and others who share its goals.

Lorna Salzman