Monday, September 20, 2010

Solution to Gridlock (not)

The BBC has another sloppy, uncritical report which almost looks like an advertisement. It's about a new small city car, which uses lightweight materials and advanced design to reduce manufacturing cost and raw material consumption. Why do the BBC think they can simply regurgitate press releases from commercial companies, lobbyists and pressure groups as if they were news?

The article is full of unsourced and unjustified assertions. This is "a car so narrow that two can drive next to each other in one lane". It's 130cm wide. Lanes are typically 3M wide. That would give nowhere near safe clearance between vehicles at any but the slowest speeds. Motorway lanes are wider - often 3.7M wide - but speeds are higher. Even ignoring this, it's not clear how two narrow cars could be accomodated in one lane - that defeats the point of lane markings. Lanes would need to be re-sized to smaller dimensions, which seems unlikely to happen.

"Such a vehicle would have the potential to prevent gridlock on the world's roads as the number of cars quadruples to 2.5 billion by 2020." How? Come on, get real. Unless cars this size make up the majority of vehicles on the road, I suspect it won't make much difference. If most vehicles are still regular-sized, lanes will be the same size and there won't me much if any increase in traffic density. The stopping distance of a small car is the same as a big car, so the distance between cars will remain the same. Hence the total roadspace required per vehicle will not be significantly smaller, except at low speeds.

"It could also help hundreds of millions of people achieve their dream of owning a car, without depleting scarce resources such as water, energy or steel." What does it run on then, fresh air? No, the fuel economy is stated as 74mpg, which is better than most current cars, but it's not going to offset a quadrupling of the world's car fleet.

Actually, I think this is where car design should be going. Currently, cars are getting bigger and heavier, tyres are getting wider and engine power is increasing, which is largely offsetting improvements in engine efficiency. As a result, with a few exceptions, vehicles are on average scarcely more efficient than they were 10 years ago. That's because car manufacturers market bigger, heavier cars because they're more profitable, while governments repeatedly fail to force fuel economy targets on the manufacturers.
Designing cars with efficiency in mind is an imperative, but it does not mean car-dependency can continue to increase without limit.

1 comment:

  1. 1.3 metres is definitely still too wide to reduce or get past congestion. A bicycle or motorcycle will have a handlebar width of about half that. And width truly matters, or else why would couriers have cut down handlebars? 1.3 metre wide cars might be easier to filter past, but they are also more likely to double up when queuing up in places where lanes are wider than the 3m minimum, which won't help cyclists. Also, the more irresponsible drivers may use cycle lanes to undertake...