Electricity is still not a given in Cambodia. I think now the percentage of the population with access to electricity is about 34% and where it is available, it is quite expensive.
Cambodia is now buying more electricity from Vietnam and the supply is more reliable. Previously because the grid was so weak and the price so high, air conditioning was a luxury and was never part of the original design of a building. Now it is still a luxury but more and more people feel they can afford it so external air con units are appearing in more and more places. Here fifteen of them have been added to the top floor of a residential block. Individual units are now not such a rarity but it will still be a while before architects think of central air conditioning for a building here.