Electric buses: Must we reinvent the wheel?


The absurdities surrounding public transit in Barcelona are many, mostly on a political level. An absolute classic which we won’t deal with today (since it’s a rather worn out topic) is the connection of both tramway system along Diagonal ave.. This project, which ought to be blindingly obvious in its utility and necessity has led to the strangest discourse on behalf of former mayor Xavier Trias who, after first proclaiming himself a strong supporter of the tram just a few years ago suddenly changed his mind after a popular (ie non-binding) referendum with little more than 10% participation about urbanistic remodeling, which he considered a reason to proclaim that he had been kissed by the muse and that he now saw clearly that what this same avenue needed is a service offered by electric buses. The fact that an electric bus is exactly the same as a regular bus just with a different mode of traction never seemed to matter neither to Mr Trias, nor to a large number of barcelonians who thought it would be a good idea to parrot something so silly.

This sudden inspiration on behalf of Mr Trias has led to a wave of demagogy mainly on behalf of politicians and media of all colours, where the main “argumentation” (if one dare call it that) revolves around proclaiming the enormous benefits of an electric bus versus the terrible tram that spits fire and eats babies. Again, noone seemed to care about making fools of themselves promoting a specific type of traction over a certain level of service or public transit infrastructure.

It’s by this strange fashion that a new word entered the barcelonian lingo: “electric bus”. Eureka! Like an apple falling on our head we’d discovered that which had always been there, but feeling especially intelligent for thinking it’s somehow something new. After all, who doesn’t like to feel intelligent? Now the question was specifying. Where are those electric buses? Where do they come from? Does Santa Claus maybe build them at the north pole? Truth be told, though this rethorical questions sound dumb, none of the politicians promoting these electric buses ever bothered to answer them. As it would turn out, our “electric bus” has little to do with the electric bus invented in the 19th century, made practical in the 1930’s and which since then has been functioning without interruption in hundreds of cities around the globe with undeniable success.

In our classic barcelonian cockines “electric bus” does not mean “electric bus”, but “electric bus without overhead wires”. Like we were going to desacrate a natural beauty like that of a city with something as artificial as some cables. Cables in a city! Who could come up with such an atrocity? Despite speaking day in and day out about electric buses, for some reason all these enlightened beings have never wanted to admit that it’s not at all a new invention, that we’re reinventing the wheel, and that there already exists a system that’s been utterly perfected and that offers excellent results difficult for an electric bus without catenary to surpass.

For starters, these electric buses we’re being pestered with don’t actually exist. Or not entirely. Battery buses have always had a limitation in their range, the distance they can cover on one single charge. For smaller buses this problem could be solved with bigger and better bateries, but it’s being difficult to do the same thing for larger buses, articulated units (in an experimental phase) or biarticulated units (non-existant). Here in Barcelona there’s two articulated units in trial service, using charging points at the end of the line to which they connect using a sort of pantograph so as to partially recharge their batteries. Other experimental buses proclaim to have ranges comparable to combustion buses, although the calculations could vary, for example if we add the energy consuption of air-conditioning on hot days and add to that the large, panoramic windows. No doubt that there’s advances being made to overcome these limitations, and likely in a few years (not more than 10 or so) articulated electric buses without catenary will be a practical reality. Yet despite of this it’s no less pathetic to propose that for a situation like Diagonal ave. we’re to opt for a system that’s still in an experimental phase, instead of an infrastructure that’s been proven to work and with impecable results, as is the case of the tram.

At Barcelona Movilidad we debated about the possible future of electric buses, with varying conclusions. It is possible that in the next few years we will see a significant change in the common mode of traction for buses to electric traction. What is questionable is the effective usefulness of this, for the simple fact that buses are already generate a very minor part of pollution, which would be even less if buses would run more fluidly (which is being seen as secondary to the change of mode of traction, showing once again the perverse priorities that pretend to solve problems by throwing money at them). However, one can also not deny that any small step does its small part. This begs the question of wether we’re proceeding in an appropriate way in electrifying bus operations. Clearly interest is set on experimental technologies which are not yet ready for practical application, with the evident and only purpose to avoid trolleybus catenaries. If the main interest were truly in electrifying bus service, this could have been done ages ago at a somewhat reasonable cost, certainly not even close to what is regularily spent on subway construction.

The economic issues, often mentioned as a reason to avoid the possibility of a trolleybus system is somewhat relative compared to the time, money and manpower being put into developing systems which are in an experimental phase. If we overcome the absurd fobia of some cables, what is most unappealing about trolleybus systems is the initial cost. Implanting a catenary and the electrical systems is not cheap, and one must add the trolleybus units which are many times as expensive as conventional buses, albeit this is compensated in the long run by a much longer lifespan and lower maintenance costs. The perception rigidity by having to follow the cable lines does not help either. It would seem that a battery-powered bus would be superior to such a system in any imaginable way. But it’s not that simple.

Some details often forgot about trolleybuses is that the very catenaries to which they’re bound are useful in avoiding the need to move to refuel or recharge batteries. Refueling or recharging a large fleet of buses is no small feat, it means time, labour and wear on the vehicle. All of that means money. It also means that the bus needs to carry the weight of energy storage. In fact, this very energy storage has always been the main problem to make battery buses practical on a large scale. Be it with batteries or supercondensers, this means a lot of weight if the bus is to hold enough charge for a full day of service. This additional weight means more energy consumption and more wear on the vehicle as well as the asfalt it runs on. This, again, means money. In the case of the system being trialed in Barcelona one must add the need for a different specific infrastructure in the form of charging stations. Without a doubt a much smaller investment than several kilometres of catenary wire, but still an investment. It also means a certain rigidity in operation, again less than that of a trolleybus, but still some.

To all this we must add the fact that these are quite new technologies. This is neither good nor bad by itself, but for obvious reasons it means a larger cost for aquiring the vehicles as well as for their maintenance. While trolleybuses have existed as a practical transport for over half a century and are a well understood technology, the same is not true for many battery or supercondenser buses, which leads to higher costs. In the worst case scenario we’d even be talking proprietary technologies which could cause costs to skyrocket as well as binding us to certain manufacturers.

Trolleybuses have none of these inconveniences. Trolleybuses avoid the weight of large batteries, so their energy consumption is lower. They also avoid needing to refuel or recharge. Although the concept of trolleybuses isn’t new, technology has greatly improved. Thus, this perception of absolute dependency from the overhead wires is no longer true. Through auxiliary batteries or engines even conventional trolleybuses are able to run a few kilometres without wires, more than enough for temporary detours.

Once again it seems that Barcelona is throwing itself toward the latest miraculous invention rather than option for conventional solutions, just so that we can avoid small nuisance which we consider below our dignity. Something similar happened with metro line L9, where the decision of using an oversized TBM ended up making the whole project much more expensive, all the while leading to a much deeper construction, which in turn makes the subway line less practical since it means losing more time in entering and leaving stations. It seems almost miraculous that when building the tram systems we got it all so right: no ground-level power supply systems, no stretches lacking right-of-way, nor absurd routes that only exist to “revitalize” an area (the TramBesòs system was in part conceived for this reason, although it didn’t hinder a relatively practical design). No doubt it’s more than ironic that this transport where we got it right for once would be the one seeing the toughest boycotts on behalf of politicians and opponents of public transit.

The “mainstream” debate about electric buses is thus little more than another embarrasing chapter in a non-debate about public transit, where appearences and uproar prevail, and not a serious analysis and rational arguments. It is once more proof of an urban consciousness which, especially in regards to public transit, is hung up and insecure, and worries more about what others will think than about the actual results. This article does not imply that trolleybuses should be implemented in any case, but it’s worrying that among so much talk of electric buses a trolleybus system is not even seen as a possibility, completely ignoring the elephant in the room. Without a doubt it’s difficult to conceive that deficiencies in public transit as well as traffic and pollution problems can be resolved while this debate is still being held at a primary school level.



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