Wednesday, February 08, 2006

More Good News

The sweaty citizens of Dubai (completely inaccurate - the runny residents would be more like it) are soon to enjoy the benefits of air-conditioned bus shelters. An advertising company - of course, what other organisation could do such a thing - has been given a 10-year Build/Operate/Transfer contract to provide this facility (Emirates Today). They will initially be managing 500 out of Dubai's 1,500 bus stops. Locations are not yet decided, but if it's advertising-driven you can bet that Sonapur / Al Quoz / Al Ghusais won't be on the list.

It's all very fine, very high-tech. But I was thinking a while ago, when this concept was first mooted. Air-conditioning only really works in closed environments. The flimsy, uninsulated glass and metal structures that we use for bus shelters now (and that the new operators are proposing) are not really suitable - the energy cost will be very high.

So why not have a look at the traditional architecture of the region. Wind towers should work superbly well. You need some solid mass in the structure (absorbs the coolness of the night and slowly radiates it during the day, thereby offsetting the solar heat gain), but the wind towers deflect any breeze downwards and get the air moving. Operational energy cost: nil.

Or have a look at other alternative cooling methods (evaporative cooling is an excellent one). Combine that with solar power and you might be able to provide cool bus stops that do not require the construction of a new power station (exaggeration!). Operational energy costs: a fraction of air-conditioning.

Either way, it troubles me that the ad company are saying they'll have stuff like recycling bins at these shelters, implying that they have some interest in the environment, when their actual solution is such a serious energy guzzler - and it's actually completely the wrong solution.