Light rail on a diet equals better mass transit
I often write about the key role the federal government plays in infrastructure. Ultralight rail is one small example of the role national governments can play in advancing or bottlenecking infrastructure change.
The state of today’s light rail: when extensively used it saves energy compared to cars. Another advantage: light rail has lower capital costs. Trains are simpler to build than automobiles. Extensively used trains also put more of their capital capacity to work, because trains operate for much of the day, where autos typically sit 22 to 23 hours out of 24 hours. Railbeds, though initially more expensive than concrete and asphalt, are less expensive in the long run than highways, which need resurfacing every seven years.
But today’s light rail has strong disadvantages too. Much light rail is NOT extensively used: an eighty-seat rail car carrying two passengers is not a particularly efficient use of either energy or capital. Well utilized light rail often becomes overcrowded during peak usage, filling up aisles with standing passengers. And even with traffic snarls, it typically takes twice as long to commute or travel crosstown by rail or bus as by automobile.
Light rail can fulfill its potential for both convenience and efficiency by upgrading from 19th century to 21st century technology, by upgrading from light rail to ultralight rail. As a beginning, light rail can shrink its gigantic passenger capacity per train to between six and twenty passengers per self-propelled car. Smaller lighter cars save capital, because they can run on lighter tracks. Such smaller cars also draw lower peak voltage than normal sized light rail. That lower peak voltage reduces electrical infrastructure costs. Even after the added cost of multiplying the number of cars is considered, overall capital system costs are substantially reduced per passenger.
If that is the only change, smaller rail cars will need more drivers, multiplying labor costs by four to twelve times. That greatly increased labor cost, which would make ultralight rail infeasible for most applications, can be avoided if the rail cars are automated, run by computer. That has the added advantage that instead of fixed routes, these cars can run on demand, with routes calculated on the fly and available 24 hours per day. When passenger buy tickets from automated ticket vending machines, as they do today in most rail systems, passengers can be grouped according to shared or proximate destinations, making routes more direct. An added advantage: since rail cars are deployed only as needed, their average utilization in operation will be between 30% and 60%. Most unneeded capacity will be parked waiting for demand. The 30% to 60% utilization includes empty cars deadheading back from lightly used stations to heavily used one, and occasional extremely late night or extremely early morning passengers who end up with rail cars to themselves.
One more convenience.: No tiny rail car needs to ever be over full. Ultralight rail can guarantee everyone a seat. And routes, calculated on the fly would also guarantee shorter more direct trips with fewer stops, with transfers being a rarity. Frequently the routes could be express, with a single pickup point and a single destination.
The smaller size of ultralight rail also enables inexpensive track switches. Those inexpensive switches, in turn, allow stops to be placed offline from the main track. Following cars don’t have to wait for the cars in front of them to load and unload passengers. The lack of bottlenecks both speeds up travel, and increases energy efficiency.
Ultralight rail may be able to match cars for convenience. No, it is unlikely that, on average, a train journey will ever be as speedy as an automobile journey, especially including travel time to and from stations. But with on-demand routes, and almost no transfers, plus offtrack loading and unloading, such trains will come much closer than today’s rail does. The real convenience gain is that with a seat guaranteed, passengers can nap, read, or work during travel – which can make up for a slightly longer journey. Conventional mass transit may advertise that option, but often fails to deliver, due to lack of guaranteed seating.
Also, conventional mass transit is often a tense experience. Automated on-demand routing means never missing a once an hour train by three minutes. If passengers arrive at a station three minutes later than intended they arrive at their destination three minutes later, just as they would in an automobile. On the fly routing also eliminates the need to worry about transfers. Most of the time passengers won’t need to transfer, and in the rare cases where they do, network communication between automated trains means passengers are guaranteed to make their transfer connection shortly after leaving the first train. Ultralight rail can guarantee no long wait for the connecting train, and no chance of missing the connection.
What about security? Ultralight rail cars can be fitted with buttons that divert the car to the nearest stop where it will be met by transit security. They can also use the security cameras that have grown common in mass transit. I’m not fond of the invasion of privacy such cameras represent, and studies have shown that they add little security to travel. But if United States residents are too terrified to travel in unmonitored proximity to other human beings, the money cost of security cameras is comparatively low.
As mentioned earlier, automated trains are less expensive than conventional rail. About 90% or more of the cost of a light rail system is in the rail bed. Even with the number of cars multiplied and the need for advanced computer systems, ultralight systems can be constructed at much lower cost per passenger than conventional light rail. Further, because ultralight really is lighter than conventional light rail, it can run on highway medians, and across conventional bridges used for automobile traffic. It can be inexpensively elevated above street level so as not to interfere with existing traffic. Because of the light weight, this elevation can be earthquake safe. (Since such systems are automated, they probably should be elevated for safety purposes in any case.)
Why are there no large scale ultralight rail system now? To some extent it is a chicken/ egg problem. Automated ultralight rail does exist in airports all over the world (including the United States) in university campuses and in other small scale “circulator” uses – where essentially there are, at most, a few short lines. But nobody wants to be the first to deploy on a large scale. Every municipality agrees: let someone else be first. Pioneers get arrows.
If nobody has deployed this kind of system on a large scale, then doesn’t that make it vaporware? Not in this case. There is only one technical aspect that is experimental. Nobody really doubts our ability to manufacture smaller rail cars or smaller light tracks to run them on. We deploy both on a small scale to today, and there are no technical obstacles to creating longer tracks with more complex layouts or to manufacturing more of the rail cars deployed in existing ultralight systems. What is controversial is large scale automation. It is one thing to automate a limited use circulator rail system. But can a full fledged train system be completely automated?
Only it turns out that is not really a question either. SkyTrain throughout Metro Vancouver, Canada is the one of the oldest and one of the longest fully-automated, driverless, rapid transit systems in the world. It has been running since 1986. SkyTrain is not ultralight rail. But it is a full-fledged 40+ mile elevated system with multiple routes. If Vancouver, Canada has been running fully automatic trains since 1986, in these days of greatly improved computer and monitoring technology, there is little doubt computer hardware and software to run automated ultralight rail exists. Given United States suburban sprawl, automated ultralight rail is probably key to our nation breaking its oil addiction. Ground transportation needs to run on electricity generated from non-fossil fuel sources, electricity, not hydrocarbons.
What about just running automobiles on batteries? Even buses can be battery operated. The problem is that batteries, even with all the recent improvements, are expensive. Over the life of the battery, electric vehicles cost more per to run mile than gasoline or diesel powered vehicles, when not only electricity but battery use per mile is included. An automated electric train system, whose automated on-demand nature and routing on-the-fly ensures decent capacity usage will cost less per passenger mile than a battery powered automobile. That does not mean there will not be a role for electric automobiles, any more than ultralight rail will make all buses and heavier forms of rail obsolete.
But ultralight rail can fill a critical niche. It can replace the most heavily used buses, making the use of transit along those routes convenient and economical. Ultralight rail will not only better serve existing riders along heavily used bus routes, but can attract people who currently drive because buses and rail are uncomfortable, slower, and often unreliable. In addition, while ultralight rail will never replace massively used transit like the NY subways, they can serve many routes with stalled proposals for conventional light rail. High speed forms of ultralight rail of up to 150 mph could replace many conventional high speed line proposals that are double or triple the cost and vary from an equivalent speed to not much faster.
What about self-driving cars? It is not clear how long self-driving cars will take to move from “cool project” to commercial technology. But it is certain that the first fully automated cars will be expensive. They will begin mostly as toys for the rich. One early adapter practical use for automated cars might be as taxis to get people from their homes to ultra-light rail stations, and from stations to final destinations. If the early version are pricey enough, though, even use as automated taxis may have to wait for less costly editions. At any rate, automated cars won’t make automated trains obsolete in any great hurry.
What about buses? After all, the up front cost of an electric bus is much lower than that of an ultralight rail system, if railbed costs are included. However, buses are a LOT more expensive to maintain than well-utilized electric rail, due to diesel engines. If buses use expensive batteries they are even more costly. Maintenance and the cost of diesel fuel or batteries alone can make buses more expensive than even conventional light rail over the cost of thirty of forty years, if that conventional light rail is heavily used. One additional bus cost that needs counting is added highway maintenance. Highway maintenance is expensive, especially with higher oil costs leading to higher asphalt costs. If added highway maintenance due to bus usage is included, life cycle cost for buses are almost always more expensive than well-utilized light rail.
What about Bus Rapid Transit (BRT)? Often BRT is just branding for conventional buses. Real BRT includes dedicating a lane entirely to bus transit. In some cases it also means running electric wires for buses to run on, transforming buses into streetcars. Given the cost of a highway lane, and the fact that it needs resurfacing every seven years, it is unlikely that over a twenty or thirty year span that a true BRT system will be less expensive than an ultralight rail system. (The reason BRT can sometimes offer better lifecycle costs than conventional light rail, is that often conventional light rail is poorly utilized. The major cost advantage, as opposed to convenience advantage, of utralight rail over conventional light rail is in capacity utilization, the percent of seats in motion at a given time that are filled.)
In addition to the usual transit haters, opponents of light rail include a certain type of ultra macho progressive. Buses are blue collar, the only mass transit a working class hero would deign to take. Trains are for effete liberals and hipsters. It is hard to tell to what extent this is left over sixties posturing and to what extent it is more contemporary sausage-fest anarchism. At any rate, those who take this view should remember the history of deliberate destruction of street-cars and trolleys in the United States between the 30s and 50s to fatten corporate profits by making way for buses.
Some of the complaints are legitimate. There have been cases where light rail is used to get people from suburbs to jobs in cities, while draining revenues from already underfunded cross town bus lines. Or in some cases light rail replaces bus lines, and certain stops are closed, usually in poor neighborhoods, especially in poor neighborhoods of color.
But an advantage of ultralight rail is that it can be run along existing bus routes and preserve all existing stops. Small ultralight rail stops are comparatively inexpensive. Of course no technology is so wonderful that it can’t be misused. But ultralight rail can at least be deployed in a way that benefits ordinary people, if we choose to do so. And it bridges the gap between current rail, much of which does serve primarily the middle class and buses, which serve primarily the poor. It can be configured, if we choose, as a technology which both serves the poor, the prosperous parts of the working class, AND the middle classes. That would mean that once built, pressure to maintain and improve it would be tremendous.
One common objection: if it is automated won’t that put bus drivers out of work? The cost advantage comes from capital savings. The automation is not aimed at lowering labor costs below those of current transit systems, but of avoiding them being up to twelve times higher per passenger mile, something that would prevent these next generation trains from ever being built. An automated transit system will require full time people in the central office to run and monitor the automated trains. It will also require full time employees close to 24/7 in, at minimum, the larger stations. It will also require floating employees who can travel to smaller stations when people need help there. Given that a 24 hour on-demand system with seats guaranteed will probably attract larger demand than conventional bus or rail, total labor use is likely to be close to that of conventional systems along the same routes.
To the extent such systems do produce substantial labor savings, there is a related opportunity to replace lost jobs with new ones. Many transit systems now have what are called dial-a-ride or dial-a-lift systems to provide mobility to disabled people who need door to door service. Demand for such services greatly exceeds supply. Every such system in the country has to triage, and is forced to exclude some people who need their services. Any bus drivers who don’t get new jobs within automated rails could be hired to expand these important van systems, for which demand will only grow as the United States population ages. Expanding dial-a-lift services is not inherent in ultralight rail. Technology, at best, has a possibility to be used to make human life better rather than worse. No technology can guarantee it will not be misused. That is a matter of human choice and political action.
However, the conservative movement in this nation overwhelmingly opposes mass transit. While some individual conservatives are honorable exceptions, the overwhelming majority of elected conservative officials, funders of conservative causes, the staff of conservative think tanks and the staff of conservative media hate trains. I don’t think this kind of technology will be implemented except as part of a coalition which cares about preserving jobs.
Why is this technology so important, at least in the United States? Because none of the breakthroughs that seemed to promise to make cars sustainable to operate have materialized. Fully electric cars, or even plug-in hybrids with a full electric range of over fifty miles remain an expensive niche market. Auto fuel cells may, at best, soon move from a pipe dream to a similar niche market. But trains are a mature technology, and automated ultralight trains are the best technical shot to offer auto dependent United States residents a practical alternative.
Initially, such trains would be best deployed by replacing heavily used bus routes. Bus diesel usage could be replaced with electricity at the same time our nation could choose to phase out the use of fossil fuels to generate electricity. This would give the people who currently take such buses a much more comfortable and convenient ride. The same subsidies currently needed for buses would cover a much greater percent of transit costs, allowing fares to be lowered as well. The greater convenience and lower fares would attract some people who currently drive.
Where most of the costs of bus systems are operating expenses, ultralight costs are primarily capital expenses. Thus, fare from additional riders would more than cover the additional cost of carrying them. No transportation system operates without heavy subsidies, certainly not automobiles. But an ultra-light rail system would start a virtuous (not vicious) cycle where the more heavily it was used, the lower per passenger subsidy would be required. That would have further positive side effects.
Proximity to an ultra-light rail stop would be valuable. Thus, development of both housing and retail would tend to take place near such stops. Existing housing and retail complexes would campaign for lines to be extended to their location, which in turn would attract more development to those locations. Ultralight rail would tend to encourage density and walkability. No technology is a magic bullet. Ultimately smart development will require smart choices. But ultralight rail will at least reinforce rather than undermine good policy.
Ultralight rail will not completely replace buses; this type of rail make sense as a bus replacement only for heavy to moderately used routes. Around the one fifth most heavily used miles of bus routes, which carry about 80% of national bus traffic, can probably be replaced by ultralight rail at a net savings. Of course, when that is done, bus routes that feed into those lines may grow more heavily used and become replaceable by ultralight rail themselves in another virtuous cycle. In addition, since ultralight rail can handle much greater capacity than bus systems can handle, it could (as previously mentioned) also be installed along many routes where conventional light rail has been proposed, but is stalled due to lack of funding.
A number of airport ultralight systems use technology designed to serve full transit systems. A number of other proposals which have never been tested in operation still make a good case that they could serve as bus replacements. It also makes perfect sense that no municipality wants to take the risk of being first. A city, town or county could commit a large portion its capital budget, perhaps the majority, on a technology that might fail. There is no doubt that the general concept makes sense, but that is no guarantee that any particular version will succeed. No local body can afford to duplicate Sam Clemen’s (Mark Twain’s) mistake with the Paige Compositor, investing in the wrong version of the right technology. This type of paradigm shift in large scale public infrastructure requires federal intervention. The United States government needs to evaluate different systems, both those already deployed on a small scale, and the most promising ones that have been proposed but never tested in operation. The feds should fund full scale deployment of the three or four systems they deem most promising, in full scale test operation in real world applications, knowing that one or more of the tests may result in failure. If even one succeeds, and there is no reason all or most of the tests should not be successful, we will have a verified technology to help wean the United States off its fossil fuel addiction, and specifically off its oil addiction. And for those who cry that testing a technology and suffering the possibility of failure is politically unfeasible: when the only politically feasible options consist of global and national suicide, something has gone wrong with the definition of “feasibility”.
We face deadly dangerous problems. But there are possible solutions too. Unfortunately every single solution is considered politically unfeasible. It seems like war is always politically feasible, austerity is always politically feasible. It seems like forgiveness for rich kids who commit murder and bankers who steal billions is politically feasible, but when it comes to jail time for a black kid in New York caught with a joint, well “the law is the law”. Years ago there was a term “crackpot realism”. I would like to update that with the idea of “crackpot feasibility”. It is time to reject crackpot feasibility. One of the multitude of “politically infeasible” changes we need is massive public spending on public infrastructure. Ultralight rail, in turn, is just one tiny example of needed public infrastructure. It is time we prove that we have more sense than cartoon lemmings and demand the politically “impossible”.
Examples of utralight rail proposals and systems:
 The six to twenty passenger range was calculated by the late lamented John Dearien, developer of CyberTran, one ultralight rail proposal. If rail cars hold fewer than a maximum of six passengers, the number of rail cars in use at any one time multiplies enough to negate most of the savings from lighter tracks. In addition, this expense adds little speed. Fixed guideway transit with fewer than six-passenger capacity is essentially trying to imitate cars, giving each passenger or family or small group of friends their own private vehicle. This is called Personal Rapid Transit or PRT. But unlike true private vehicles, PRT still travels from station to station. A larger rail car, that carries a few more people and makes one or two more stops over the course of at trip won’t arrive at the last stop more than a few minutes later than the PRT car at a much lower capital cost and slightly lower energy costs. Ultralight rail should be modeled on the elevator, not the taxi.
Why the twenty passenger upper limit? Beyond that, and maybe even at a carrying capacity of twenty passengers, the odds of combining high capacity use and convenient routing drop. Probably even twenty passenger capacity should be saved for high and low end systems – high speed between airports, and low speed circulator systems. For crosstown and commuter systems, which I hope will be the bread and butter of future ultralight rail, around a twelve passenger capacity is probably right. Aside from efficiency issues, a twelve passenger vehicle is large enough to easily be designed to accommodate disabled passengers, and can ensure that most large families can travel in a single car, though not the Duggars or the Bates.
 Ironically many of the newer ultralight systems run on batteries. This is not because battery operation is cheaper in the long run, but because ultralight rail entrepreneurs are out to sell their products to capital starved municipalities and capital-thrifty private developers. Battery operation cuts initial costs. Running off of “third rail” would save money over the course of twenty or thirty years, but in practice buying decisions are usually made on the basis of initial cost. This is an example of why, even when dealing with an industry based on exciting and promising technology, independent evaluation is needed. Batteries probably do have a number of optimal secondary roles in ultralight rail: regenerative braking, emergency backup for power outages, and to lower the cost of railbed by allowing short gaps without a third rail, where not powering hard-to-electrify short spans saves more than increased battery use costs.
 Changes in utility regulation also contributed to the destruction of the street car. Many of the trolley systems destroyed by the conspiracy were already in bankruptcy. It can be argued that the murder was of an already dying system, that was not dying quite fast enough to suit powerful corporations in a hurry to replace it. But no one disputes the existence of a deliberate conspiracy by GM, Firestone Tire, Standard Oil of California, Phillips Petroleum, Mack Trucks, and the Federal Engineering Corporation to purchase streetcars and trolley system and convert those systems into bus systems in order to sell more cars, buses, oil, tires and other auto-related goods.
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