2. Some university dormitories don't have air conditioning, because schools use electricity centrally. If you use high-power electrical appliances, it is easy to cause power outages and fires, which is very unsafe. However, with the heat in summer and the cold in winter, schools have begun to install air conditioners in dormitories, but using air conditioners may trip, because air conditioners are high-power appliances, and students may not use them often.