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Redesigning Transportation

The U.S. transportation system is arguably broken -- or, at least, in serious trouble. From traffic jams to gasoline prices, suburban sprawl to highway subsidies, the system we have at present is not the one we would have chosen, had we known what we were in for. WorldChanging readers know all too well the panoply of globally-devastating second-order effects arising from voracious oil consumption. The solutions at hand (hybrid cars, "hydrogen highways," smart road info, parking taxes, and the like) are more akin to spot fixes than real transformation. Is a greater transportation revolution possible? What would it look like?

Bruce McHenry thinks he knows.

McHenry is a technology entrepreneur, and has lately been working with a group of urban planning and vehicle technology specialists on a plan to completely reshape transportation as we know it. In an essay entitled "Three Key Developments for Surface Transportation" (originally published in MIT's alumni journal), McHenry argues for a nationwide shift to grid-powered electric car guideways, replacing both light rail and highways. Such a system would allow for individual transit on surface streets as well as "platooning" on guideways: clustering vehicles as mini-trains, connected not by hardware but by networked software controlling vehicle speed and direction. Platooning makes groups of vehicles much more energy-efficient, and "traffic collision avoidance system" (TCAS) technology would allow for higher speeds with far fewer accidents.

I won't recap the entire piece here; if you're interested in transportation technology, McHenry's piece makes a strong case for the wholesale replacement of our current transit system with a network of electrified guideways. He also links to a Powerpoint presentation (5.5 MB) laying out the costs and benefits in more detail; it's worth the time to look through, and is "open source" content. The e-guideway network certainly wouldn't be inexpensive to do, probably on the order of more than a trillion dollars, an amount roughly equivalent to the cost of the national highway project of the 1950s. The costs could be recovered over time through fewer accidents, less oil consumption (especially when those globally devastating second-order effects are counted), and time saved using faster, more efficient, travel.

McHenry's concept of a transportation revolution isn't the only replacement option, but it does do the math better than many others that I've seen, and is more realistic than calls for everyone to shift to bicycles, abandon the suburbs, and/or only take buses.

When a system is broken, is it better to repair it or replace it? You can make a good argument for either approach. Repairing a broken system is less wasteful, can cost less in the near term than replacement, and allows for ongoing feedback via incremental improvements. Replacing a broken system allows one to discard the now-unneeded legacies of past solutions, introduces a system which can be more appropriate to present and future concerns, and can save money over time when compared to a series of incomplete fixes. Too often, however, we don't get a chance to choose. We go with incremental fixes not because we've decided that they provide the best cost/benefit ratio, but because they're cheaper, easier, faster or just less apt to lead to troublesome debate.

We may decide that a gradual transition to more hybrid cars, then fuel cell cars, along with a slow adoption of TCAS technologies (and smart road info and parking taxes), makes the most sense. But we may also take that path not because we've decided on it, but because we just sort of let it happen. McHenry's vision of electrified guideways criss-crossing the continent may not be the best solution, but it does prompt us to think about our transportation choices more. Whatever we choose, we'll be better off having given it a bit more thought.

Comments (17)


Electrified guideways? And the rule of thumb for electricity is about 33% efficiency - 1/3 lost in generation, 1/3 lost in transmission.

Alliance for Global Sustainability, which is also MIT affiliated, did a study on sustainable mobility a year or two ago and they couldn't figure out a solution.

Oh well. I still have my bicycle.


Have no fear the army and big bussiness already came up with the answer.

Using a combo of h2 ice and later h2 fuel cell and new 10kpsi storage tanks you can get a good 300 mile range on a hydrogen car.

hydrogen can ge generated through various manners without costing too much as a fuel and unlike electric energy it doesnt get wasted in transport from an energy rich region such as say a desert solar array or an ocean wave array or a nuke or fusion plant to the point of use.

Mind you most hydrogen systems will be hybrids and as such as batteries get better it will be more and more electric less and less h2 assuming cheap energy is present.

Actually, George, the efficiency of current fossil powerplants is about 33% (going up a bit because of combined-cycle capacity coming on line); check this out from the historical heat rates.  Transmission is upwards of 90% efficient.

I don't think that a revolutionary approach such as guideways is going to have a good chance of working; there is the problem of infrastructure support affecting demand which affects infrastructure, the classic chicken/egg problem.  Plug-in hybrids have high potential for fuel savings regardless of the type of roadway, adaptive cruise control can save fuel and speed traffic regardless of what the rest of the vehicles on the road have, etc.  These have much more potential for progress (faster and cheaper) than a system which requires new roads and new vehicles.


The proposal is brilliant on the details, disappointingly uncritical about the assumptions.

Whether H2 or batteries are the energy carrier, the question remains: how will the energy be generated to power such energy-intensive systems? And what will be the environmental, economic, and political effects be of having to generate this energy?

It seems as if the major problems ahead of us are global warming, conflict over energy, and the probability of peak oil. This proposal, otoh, addresses problems like traffic jams and gas prices, which are several orders of magnitude less important.

I would argue that it is bicycles, walkable cities, and mass transportation that are the realistic alternatives, given the future of energy.

Bart, we have a wider range of renewable sources for electricity generation than for individual vehicular power.

I don't want to be in the position of defending McHenry's notion as the only alternative, because it's not, but it *does* address the bigger questions of energy conflicts, peak oil, and global warming. The powerpoint is more explicit than the article, so if you didn't pick up on this, it's understandable.

The physical infrastructure and social transformation required to make bikes, dense urban living and reliable mass transit the default options everywhere are even larger than those required to get something like the e-guideways notion up and running, sadly.


Thank you Jamais, for pointing out the slide presentation. It is a neat technology and would be a wonderful project -- if one shares the assumptions of the 1950s and 1960s. Maybe that's the reason the slides feel as if they're from that period of innocent optimism and unlimited resources.

I see three main problems with the proposal:

1. High-speed personal transportation is assumed to be a paramount goal worthy of huge expense. A slide titled "Transportation Is Vital to U.S." has bullets showing the % of income spent, miles traveled, and energy used on automobiles. What this slide really proves is that "Transportation Is COSTLY to the US."

I can think of many things that should be a higher priority than personal transport.

2. The sources of power for the system are uncomfortably vague. Solar, wind, "meltdown-proof" nuclear MIGHT be used, says McHenry. None of these are cheap, nor can they be ramped up quickly. The history of the last 30 years and the present piddling efforts give no confidence at all that they could enable the required doubling of electric capacity.

3. The price of the system is vastly underestimated, since it doesn't include the required DOUBLING of the electric generation capability. Likewise the efficiency of the vehicles is over-estimated because it doesn't include the cost/energy required for infrastructure.

I guess I am fixated on reducing demand, rather than making minor improvements to present high-energy systems. Rather than invest billions so Joe Sixpack can zip off to Disneyland, why not encourage local communities to become rewarding places in which to live?

I have personally experienced the efficacy of demand reduction. When we were looking for a place to live, my wife insisted that we settle in a community in which she could walk everywhere. How right she was. We don't need a hybrid or an e-Guideway. What we need is for gas prices to triple, so the traffic becomes less crazy and small local stores can survive.

Jerry McManus:

Many of the benefits of this 'smart car' approach to energy and transportation efficiency can be realized with Automated Highways (AH), but at a much smaller cost (at least in terms of infrastructure), and with a much more realistic prospect for near-term deployment.

The basic idea is that the vehicles, not the roadway, has the bulk of the technology required to not only drive themselves, but to also network with other cars on the road and, crucially, to network with the entire transportation system. This would involve upgrading cars to include technologies like forward looking radar, radio communication, and robust computer control. The only changes needed on the highways would be the addition of inexpensive magnets embedded at regular intervals in the automated lanes, wireless network nodes along the side of the highway and, of course, specialized on and off ramps for the smooth transition from manual to automated driving.

This approach would be more realistic for two reasons. First, integrating AH into the existing infrastructure would be fairly straightforward, there is no requirement to completely re-invent the transportation system. The first AH lanes, preferably segregated from the non-automated traffic flow, could be deployed on existing car pool and HOV lanes with an investment on the order of thousands of dollars per mile instead of the millions, or billions (think The Big Dig) per mile that would be required for a more radical solution. As the technology matures then it can be deployed to more of the existing highway lanes and eventually to many surface arterioles.

Second, the bulk of the cost of upgrading the vehicle fleet would be carried by consumers. Certainly there would be government subsides and tax breaks offered as incentives, but it would be primarily free market forces that would drive the upgrade cycle. People that can afford the luxury of letting the car do the driving would be the early adopters, and yes, this would give rise to charges of class discrimination and so called 'lexus lanes', but eventually as the technology becomes more ubiquitous it would also become more affordable. The simple laws of supply and demand would then drive the transformation to a saner, safer, and much more intelligent and efficient transportation system. Maximum efficiency would be realized when humans no longer do ANY of the driving and vehicles across the entire automated network are smoothly routed from point A to point B.

Tom Volckhausen:

This is a muddled solution to an improperly defined problem, a massive and inflexible effort to bandaid over poorly designed cities.
People are already voting with their feet and their dollars for well-designed urban spaces which can easily be traveled on foot and by transit. All the cities I see in the US are busy densifying in the most desireable areas, a kind of market driven "unsprawl".
Would a city transected by legions of automated, platooned electric cars be a place any of us would really want to be?
This idea belongs with the Jetson's sci-fi dead end dreams.

John Laumer:

Current transportation system evolved over 50+ years. Since the interstate concept was deployed, Federal role has always been to manage the money. No grand systems planning occured that fused vehicular and corridor designs. What basis is there to assume that such a grand scheme could work? Give an example of comparable scale? NASA is tiny by comparison. Designs will follow human intent, not the other way around


There are a few good reasons people dont bike.

1 The seats.

2 Weather.

3 Homicidal maniacs and pms women in cars.

4 We look UGLY in shorts.

There are many reasons we dont use mass transit.

1 We hate you and if forced to ride the bus with you would kill you sooner or later wich would cut into our leasure time far too much and cost too much in lawyer fees.
2 We hate buses and trains.

3 Its just a pain to transport illegal booze and drugs on a bus.

4 Everyone gets whiney when you fart on a bus or sing badly to rap music and big hairy guys singing the theme song to my little pony scare people...

5 You just cant bring a life sized my little pony sex doll on a bus.. you can however fit one in a large suv.

6 Poeple never are willing to answer the question where do you get off to go to the my little pony s&m bondage faire.

7 Have you ever tried to get on a bus wearing a zebra print spandex suit and a neon green tutu with stilletto heels at 3 am?

The fact is you should be very glad many people DONT ride mass transit.

In my “retirement” I have worked with a great many dualmode advocates including Bruce McHenry, the author of the MIT alumni article that Jamais Cascio reviewed here. Let me report that Bruce is a very sharp individual, and he has thoroughly researched the pros and cons of dualmode transportation. His resulting conclusions are not to be taken lightly. It concerns me that this field is so complex (more from sociological than from technological standpoints) that numerous inadequate solutions, even though seemingly put to rest by analysis and practical logic, keep popping up. Endless debates ensue, and broad consensus is elusive. It is the age-old problem: “Why can’t they see that we are right and they are wrong?”

I agree with most of what Bruce writes, but for the details of my own proposed dualmode system, I refer you to, http://faculty.washington.edu/jbs/itrans/reynoldsfuturist.htm, (nontechnical) and to, http://faculty.washington.edu/jbs/itrans/hilo2.htm (semi technical.)

Referring to the previous comments here: Gmoke wrote that Alliance for Global Sustainability couldn’t figure out a solution for sustainable mobility. As the extensive literature shows, other people have. The solution is called dualmode transportation.

Wintermane is sold on hydrogen energy. There are a number of companies working on hydrogen-energy developments who are putting out a lot of misleading hype. Making hydrogen from water by electrolysis is an inefficient process; and the resulting H2 is not a source of energy but a carrier of energy, just as electricity is a carrier rather than a source of energy. Making hydrogen from petroleum or coal is also inefficient; we end up with less energy than we would have had by using the fossil fuels directly. And, we would still release global-warming carbon dioxide from the hydrocarbons, but we would move the point of CO2 release from the streets and highways to the hydrogen plants. The argument that we could eliminate the CO2 from car exhaust by using hydrogen is a red herring if we make that hydrogen from fossil fuels.. If we use “reforming” fuel cells in the vehicles and power them with methane from natural gas, we would release the carbon dioxide on the highways again. Fundamentally, the problem with hydrogen power is that we don’t have any hydrogen, and more energy is required to make it than we can get back.

So, for portable energy other than petroleum to carry in a vehicle there are batteries having low energy-to-weight ratios (around a tenth that of gasoline) and short shelf lives; and we will have fuel cells and hydrogen-storage systems with largely these same problems. But it needs to be pointed out that with dualmode transportation the limitations of alternative portable energy systems will be far less serious, because we will be using the manual street mode for only short distances at low speeds. Most of our traveling will be done on the automatic guideways using power-grid energy.

“Engineer-Poet” mentions the chicken-and-egg problem. The implications of that child’s riddle don’t seem to me to be of major concern. We somehow have both chickens AND eggs, we have railroads and rails, and we have cars and streets and highways. Naturally we will design and build all parts of the new system simultaneously. Certainly there will be major disruptions, discord, and horrible growing pains, but that is par for the course with anything of this huge magnitude. The bigger the project the greater the pain. But we know that traffic can’t expand much more under present conditions, we know that global warming is escalating, and we know that we are about out of petroleum. These are major world crises and they require a revolutionary solution. A single solution in this case, because fortunately dualmode alone will go far toward solving all three of these crises. As the saying goes, don’t try to solve vast problems with half-vast ideas. This will be and has to be a major technological and sociological revolution.

Poet also speaks of conservation. By all means let us conserve oil as best we can (those of us who don’t drive SUVs, anyway). But improved conservation can only delay, perhaps by a few weeks, the day when the price of gasoline reaches twenty dollars a gallon. Be realistic—our best conservation efforts can only slow down the development of these three crises a little. We must face up to the future; we can’t responsibly limit out thinking to tomorrow or just a decade or two from now.

Bart proposes bicycles, walking, and mass transportation as the “realistic” alternatives. And he would like to reduce demand for transportation. These are regressive rather than progressive steps. Dualmode offers us a most promising “realistic” but admittedly very difficult alternative to going back to nineteenth-century transportation and lifestyles.
Bart might be happy with just a bicycle, but I would not (I own one but seldom use it.) The continued use of private cars is going to be demanded by a few hundred million people worldwide. Dualmode and only dualmode will be able to meet that demand without petroleum.

Bart also raises the question of where the needed electric power is going to come from. That is a vital question, and a tough one. People who like fish don’t like hydroelectric dams. Nuclear fusion provides power but also nasty problems. The development of practical solar-cell farms, wind turbines, bio-fuels, wave power, and others options are disappointingly slow. This is largely because the power-density per acre of land or sea of all of these options is very poor compared to fossil fuels. Raping the world’s timber and fossil fuels—especially over the last decade or two—was very much easier. It took nature millions of years to accumulate the fossil fuels, and we have used most of them up in less than a century.

Roughly half of the electricity used in the United States is from coal. We have enough coal left to last for a hundred years or more, but coal has many disadvantages. And what will happen to civilization when the coal is gone? A nearer-term one that scares me more than coal depletion is natural-gas depletion. There is now much effort to use natural gas in transportation. We are told that natural gas reserves will last longer than the petroleum will. But it won’t be very much longer, especially after the oil is gone and we have to convert everything to use gas. Actually heating, not transportation, may be the greater concern. Out wood is mostly gone. We largely stopped heating with coal long ago because it is messy and labor intensive. Most home and commercial heating in the US is now done with oil and natural gas. I for one would rather stay home and be warm than travel and come home to a permanently cold house. Not only will we need a huge amount of additional electricity for transportation, we will need it for heat.

I have a certain amount of faith that we are going to achieve practical, safe, inexpensive, limitless controlled nuclear fusion in the not-too distant future. I wish that faith were stronger.

Dualmode transportation will use electricity in both modes. Jamais pointed out that we have a wide range of sources for the generation of electricity. Electricity can be made from any source of energy, so regardless of what source or combination of sources we end up using we will still be able to use dualmode transportation in both modes. But when the oil and natural gas are gone internal-combustion-engine vehicles including boats and airplanes (which don’t fly well dragging long extension cords) will be stationary.

Jerry McManus supports automated highways instead of automated guideways. Automated highways are obviously a less expensive approach but they couldn’t begin to accomplish what dualmode guideways can in terms of safety, speed, and system capacity. AH would only reduce our traffic problems a bit; and they would worsen rather than help solve the petroleum-depletion crisis and the global-warming crisis. Compared with dualmode guideways with electric-grid power, an AH system would be penny wise but pound-foolish. The US Department of Transportation withdrew funding for AH efforts some years ago, for good reasons.

Finally, Bart mentioned the huge cost of a dualmode guideway system. Yup, it will be enormously expensive. Someone, or maybe several of us, have suggested that it will cost in the order of a trillion dollars! So what? What did our highway system cost?
The dualmode guideway system will not have to be paid for by increased taxes or by increased national debt because it will be in tremendous demand and will therefore be an excellent investment. It will pay for itself, earn a profit and could even pay taxes (from automatically collected use fees in place of gasoline taxes). Almost everyone, every business and every transit system will use it. It will eventually largely replace many highways lanes and the arterial portions of our street systems.

Bart, I agree that “we need gas prices to triple,” but my reasoning is different from yours. We need gasoline to be much more expensive, and the sooner the better, so that this nation and the rest of the world will be forced to recognize the rapidly approaching crises resulting from continued use of obsolete twentieth-century transportation systems. The need for our twenty-first century transportation system is urgent. Dualmode is by far the most logical choice, all factors considered.

Francis Reynolds

Thank you, Francis, for the comment. I'm working on responses to some of your points, but I just wanted to acknowledge the thought and detail that went into your post. Thank you.

A comment like Francis' deserves a reply.

The hydrogen debate plays out on WorldChanging on a regular basis. Some of the contributors here are quite certain that hydrogen will be the fundamental element of a new energy economy; others emphasize the current inefficiencies of hydrogen production, and the danger of relying on reforming hydrocarbons. But there is broad agreement that the current technologies are not the ones we'd be using. Direct solar "cracking" of hydrogen from water, for example, appears to be potentially much more efficient than electrolysis; the generation of hydrogen from microbial activity, as another example, is showing quite a bit of promise as a renewable and energy-efficient process. Getting the hydrogen for use in fuel cells may turn out to be much less of an issue than reducing the prices of the fuel cells themselves.

Dr. Reynolds shouldn't be so quick to discount conservation. Improvements in building and vehicle efficiency could do much more than delay the final oil crisis by a few weeks. It turns out that there is a lot of room for efficiency improvement in most building and vehicle systems, and demand could be significantly reduced by more widespread adoption of energy-efficient changes. This doesn't solve the problem by any means, but it does open up our options (for example, off-grid solar and wind power for buildings is much more feasible if building energy use is low).

The biggest drawback to the dualmode system proposed by McHenry (and nicely elaborated upon by Dr. Reynolds) is the difficulty of an incremental or evolutionary transition from the present system to the dualmode. Not that incrementalism is always good -- one of my favorite jokes from the old Soviet Union concerned the decision to switch from driving on the left to driving on the right: "the first year, they had the trucks change..." -- but a more gradual transition allows for economic reality, given the admittedly enormous expense involved. Unfortunately, if the dualmode roads don't work well for traditional vehicles, and the dualmode cars don't have sufficient standalone range for commute drivers, slow introduction of the system could leave us in a "worst of both worlds" situation.

I would expect to see someplace outside of the United States be first to adopt a technology like dualmode. It would be a place with less area to cover, with more comfort with government diktat and more willingness to try something new. Singapore, for example, would be an ideal first place to implement dualmode. Dr. Reynolds, do you know if there has been any interest in dualmode outside the US?

Jamais regards the largest problem with dualmode transportation to be the transition or evolutionary problem. Two inventors have paid special attention to this problem and both offer solutions that have merit. One is the Danish RUF technology (www.ruf.dk) and the other is the Mega/MicroRail technology (www.megarail.com). The RUF concept would use small dualmode buses on the guideway initially (8 passengers, operated as dial-a-ride,providing door-to-door service)followed by personal dualmode vehicles using the same guideway as the dualmode vehicles become available. Over time, the mix between MaxiRUF vehicles and personal RUF vehicles would most likely trend toward the personal RUFs. MegaRail has been designed with full dualmode capability as a longer-term objective but would start out with small vehicles captive to the elevated guideway under manual control plus "carriers" that could handle conventional vehicles during a transition period. Eventually, all the vehicles would have dualmode capabilites, be controlled by the system and the carriers and manual operations would be phased out. The same guideway built initially could be used throughout the transition period and would continue to be used after the transition was completed. Many other inventors have proposed using "pallets" or "carriers" to deal with the movement of conventional vehicles initially as well. For details, see http://faculty.washington.edu/jbs/itrans/dualmode.htm and for extended discussions of these issues see http://faculty.washington.edu/jbs/itrans/dualdbte.htm

Jerry McManus:

"Automated highways are obviously a less expensive approach but they couldn’t begin to accomplish what dualmode guideways can in terms of safety, speed, and system capacity."

What is the basis for this comment? Many of the features that would be required in a 'smart car' capable of travelling an AH are already being offered as SAFETY features on newer model cars. The speed and system capacity of dualmode guideways are realized primarily through 'platooning' of vehicles, a feature that is also fully implemented by AH.

"AH would only reduce our traffic problems a bit; and they would worsen rather than help solve the petroleum-depletion crisis and the global-warming crisis. Compared with dualmode guideways with electric-grid power, an AH system would be penny wise but pound-foolish..."

And what exactly would prevent electric vehicles from travelling on an AH? Is it possible that once an AH infrastructure is in place then it would be that much easier to require consumers to purchase electric or hybrid smart cars if they wish to take advantage of the speed, safety and convenience of AH?

"The US Department of Transportation withdrew funding for AH efforts some years ago, for good reasons."

And those reasons are...? I would be very interested to see what facts your arguments are based on, facts which seem to be conspicuously absent from the blanket assertions in your above post.

Jerry McManus:

For those who may still be skeptical about autonomous vehicles travelling automated highways I invite you to read this excellent article by the world changers at the EE Times:


With additional comments found at the blog of the always timely Roland Piquepaille:


The vehicle guidance on a RUF guideway (www.ruf.dk) is much safer than the electronic guidence in an Automated Highway (AH). RUF vehicles are locked to the guideway and cannot derail.

AH platooning is difficult because the vehicles change gears differently. Electric motors are easier to control.

A separation of 2 meters is not as safe as a separation of 10 cm. Also the reduction in air resistance is much better in a system (RUF) where the vehicles are created for that purpose and are coupled closely on the guideway.

AH with electric vehicles is possible, but you cannot supply power to the vehicle during the trip. In a RUF system, all vehicles can recharge their small batteries from the power collected from the guideway.

The most difficult part for AH is probably the implementation phase. If you convert a lane to AH, you will need to reserve that lane for automated vehicles. That means an immediate drop in overall capacity because not all vehicles will be able to use it. After a transition period, there may come an improvement but it is uncertain how big the improvement will be.
A RUF system is isolated from the existing highway system so it will add real extra capacity.

I invite you to try the following programs describing different aspects of the RUF system:
www.ruf.dk/rufsim.exe and www.ruf.dk/rufsim.doc

Palle R Jensen
RUF International


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