| Using an aircond has very poor power efficiency if you have only simple windows. You can notice this by cooling a room to e.g. +25'C, then switching the aircond off: in few minutes it's the hot air is back. Adding/changing to double windows can keep the cool inside and hot outside (or vice versa) a long time in the whole apartment. Thermodynamically, a single glass is almost as good as no glass at all. Double glazing pays itself back quite quickly, since you'll be saving in electricity.
Carsten wrote about double/triple glazing and insulation in north Europe. For exactly the same reasons it should be applied also here: keeping the inside temperature different from outside temperature. But of course, in a damp weather you must be ventilating the rooms once in a while, otherwise the walls and places may start growing stuff. In many "luxury apartments" built in 90's they have this problem: nice temperature but it's a moisture trap. |
Shanghai is Experiencing Energy Crisis