When I first started this blog, I did so with the conviction
that what PRT needed was some sort of standardization – a way to allow PRT to
be a joint venture between specialized companies doing what they do best,
instead of some little startup trying to be ten companies at once. That way a depth of resources could be brought
to play that could never be matched by any other method, except, perhaps,
direct government subsidies.
Times have changed and things are changing faster by the
minute. This was spelled out to me, yet
again, as I was writing my last post on forward-compatibility and
extensibility. In that post I outlined a
“last mile” strategy, and it involved slower, bare-bones loops within loops –
almost like big long circular driveways. This represents an important call… A call for
a plurality of speeds. (I have called for high speed routes as well.) This requires a degree of control complexity that
seemed pretty far-fetched just a couple of years ago.
A related topic involves vehicle size. Many see the utility
of using the track for other purposes beside strictly passenger service. Freight
could be delivered, for example, straight into buildings and even into offices
or down store isles with vehicles specifically designed for the task. Many will
also agree that there might be some cases when passenger vehicles of differing
sizes would be appropriate. That means that these two qualities (multi-speed
and multi-sized) would require a track that would support such configurations. A
system designed to be forward-compatible and extensible into the relatively
distant future should, therefore, ideally incorporate such possibilities in a current
track design, even if such features are not part of the current system
iteration.
One problem with getting the most out of the infrastructure
that this track represents is the question of ownership and maintenance. Back in the day, PRT was thought of as one big
machine, presumably operated by a specialized team stationed at the terminals
of some giant mainframe. Now, with
distributed computing, cloud based sharing, dirt cheap sensors and the rest, there
is real question as to how much will really need to be done centrally. After all, if you give Google’s automated cars
their own lane and program them to pick you up, taxi-style, haven’t you just
created a PRT system that is essentially like ULTra? The key point, it seems to me, is vehicle
autonomy. If positionally-aware, constantly
communicating vehicles can take current traffic data and pick (and report) their
own routes, and they can be made to establish safe headways and merge safely,
then managing the system would potentially be much simpler than what is
currently done by law enforcement for our roadways. Taking the intelligence out of the track, it
appears, has benefits. Is “dumb” track
the most forward-compatible and extensible choice? Quite likely, I think. It is also cheaper and therefore more
extendible in terms of coverage, and is less “breakable” as a system. Thank goodness for technological advances!
It may even be the
case that it is easier to get through regulation hurdles with autonomous
vehicles on dumb track. After all, it’s
hard to argue that a tracked environment is somehow more dangerous than the
unpredictability and traction-dependence of city streets, where driverless
automobiles would go. Also the specter
(or assumption) of larger, multi-passenger vehicles seem absent from the safety
discussions at present. I don’t believe
Google’s robocars have had to pass any APM (Automated People Mover) standards
and they certainly haven’t been subject to the arcane rules designed for
trains, something that has been of arguable concern in PRT circles.
Let’s bring standards back into the discussion. As I said in the opening, I have long been an
advocate of open-source standards for PRT, so that a system can be made by a
multiplicity of specialized companies. But I am also very wary of setting
standards too soon, as they could rope the whole effort into one that favors an
inferior design or soon-to-be obsolete technology. One important reason to establish them,
though, has to do with the PRT business model.
From a point of view of doing the most for society and the
wellbeing of the planet, the best model would be for the track to be open to
all qualified vehicles…any and all meeting certain standards. There is every reason to want to take as many
vehicles off of the roads as possible, and so there is good reason to make the
track as versatile as possible in that regard. This brings us right back to extensibility and
forward compatibility. Note that I said
“model” and not “business model.” From the
“PRT business” point of view, designing for the distant future makes no sense. Any PRT startup has no choice but to begin in
the least complicated way possible. In
terms of overall long-term business growth, though, it makes great sense. What is good for society and the planet also unleashes
all sorts of potential business models that cannot exist today. Maybe tiny delivery “bots” will bring you your
pizza. Wouldn’t that beat the current
paradigm of using a person, fossil fuel, and a multi-ton vehicle to do the job?
The point is that extensibility and
forward-compatibility are only useful to a business insofar as they relate to
their best financial interest in the relatively near future, and therefore
their designs will reflect this, even if those designs do not reflect the best
interest of the environment, traffic mitigation, or other such benefits.
I envision a business model where a PRT company serves as a
general contractor and business partner with a city, but whose role gradually
diminishes with time. In such a scenario
the revenue stream and responsibilities gradually shift to the city, although
obviously the PRT company could always be kept on for whatever role is agreed
upon. The important point here is that
the PRT company’s exclusive rights to the track should have an endpoint. This would seem attractive to the city, since
it does not have to grant never-ending monopoly status to a company that may or
may not live up to expectations.
This is where design extensibility and forward-compatibility
meet open standards, business viability, as well as societal and ecological
priorities. Although it makes no sense
for a PRT provider to design a track that can, someday, more efficiently
deliver pizza, mail or bags of cement, it makes more sense to the eventual
owner, the city. The city’s needs are much
more closely attuned those environmental, societal and macro-economic problems
that PRT has such great potential to solve.
This mismatch between a PRT provider’s needs and a city’s
needs directly influence the desirability of PRT as a meaningful alternative to
other transportation solutions. If PRT
is to represent a prudent investment in the future, there should never be a
possibility of having to scrap miles of track because of aging vehicles or an obsolete
operating system, or a bankrupt PRT company. Every component should be able to be updated –
forever. Perhaps this is why, although rail-type
PRT offers numerous advantages over pavement based systems, it is the latter
that is making the most inroads. An
elevated mini-roadway may not be what I would prefer to have going down my
street but it is clearly an extensible choice. It could be used for bicycles, scooters, golf
carts, pedestrians, manned electric taxis, whatever. This represents a safer investment for city
planners, even as it caps routing choices and speeds.
A standardized PRT platform that is easily adapted and
upgraded would similarly represent a safer choice, if the various parts of the
system were sufficiently simple. The
owners (the city) should preferably have a system where they could simply take
bids for repair, replacement, expansion, etc. The main danger is that such a standard will be
a bad one.
It seems to me that building a good standard should be a lot
like building a sound structure… Start
with a sure foundation. This can start
with a wish-list. The two listed above -
to allow multiple speeds and multiple vehicle types, are neither required nor
advantageous in early iterations, and so without the altruistic guidance of forward-looking
standards such qualities could take many decades to see the light of day. The same could be said of multi-axis capabilities,
guideways that can carry street lighting and utilities, and other qualities
that might be on our list. But if we
really want PRT to make a dent in the miserably obsolete transportation status
quo, we need to look far ahead and plot a course.
Standards can be very exact and legally precise or vague but
definitional - a “standard” putter, for instance. The latter, consensus-driven definition always
precedes anything more exact, and there is not a great deal of consensus on PRT
design. But what can we generally agree
on in terms of PRT’s eventual role? About the objectives that are important to the
environment, the society, the economy, etc.? What qualities will create the potential for a
pervasive system? What qualities will eventually
permit the most efficient management of the system?
4 comments:
I think rather than a PRT manufacturer trying to make a substantial profit on selling system components, they would be better off giving the purchaser the right to buy components through competitive tender using the company's IP, but in exchange for a 50 year royalty of x cents per passenger mile, and y cents with freight tonne, in inflation-indexed terms. This, I think, would help to align the interests of the city (or other purchaser) with those of the PRT manufacturer/system designer. It then allows the system to be sold at cost or cost+a small margin, and shift more of the cost into a discounted stream of success-contingent revenue. This lowers the up-front risk for the purchaser of the system. It would also get around the problem of short term patents...
Dan the Blogger thanks alert reader Andrew for breaking the silence! Oh! On a related note… That widget or gadget that used to list comments stopped working. It never was a Google product and maybe the authors will get the bugs out, in which case I’ll put it back… Anyway, back to the subject…
I think that some kind of a cut of the fares or (equivalent) going forward should be part of the mix, for sure, and reliability incentives seem like a no-brainer as well. It seems wise to separate the various aspects, such as vehicles from track from stations, etc. in the final mix, since each has its own dynamics. Vehicles will be tricky, because someone will want money at the end of manufacturing process (or earlier) yet they would be the first thing to break or wear out. Perhaps the PRT provider will act as a financing company and guarantor in this respect. I would add that the structure of any deal for a largely untested system would be totally different than what might evolve in later projects since each and every player will initially be extra cautious.
To reiterate a point from the post, the reasons for a specific design choice can be more than what is extensible, (flexible in terms of extending its usefulness) and forward-compatible. (The parts work in future iterations.) A good design should also reflect flexibility in terms of business models. It still remains to be seen how discreet the various parts of a PRT system can be and still function as a seamlessly functioning and fault-proof whole. If the entire system can be completely broken down into very small, individually-improvable parts, that will have profound implications for how the whole business, including the marketing, should be structured.
Early systems, I think, will be like ULTra-Fairwood, where a consortium essentially internalizes all the risk and designs, builds and operates the system in exchange for fare revenue.
The trick seems to be creating an effective incentive structure to encourage making IP/standards available for other firms to use.
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