in 1980s, he visited one of hist college friends in beijing. his father was a minister (can't remember which ministry though). it was really hot summer and my friend just asked his friend why don't turn on the AC. back then AC was something almost unheard of for most of chinese people. his friend's brother was a ph.d student in japan and bought one for his parents. to my friend's surprise, his friend said it was too expensive to use it, they can't afford to pay the electricity. they spent most of their time in the building of the ministry to escape the unbearable heat during the summer time.