Group 1 - The article discusses the energy-saving strategies for air conditioning usage when leaving home for a short period, specifically comparing fixed-frequency and variable-frequency air conditioners [3][7]. - Fixed-frequency air conditioners consume a constant amount of energy, and it is more economical to turn them off when leaving for a few hours [3][5]. - Variable-frequency air conditioners are more efficient when left on for short periods, as they consume less energy during operation compared to the energy required to restart [3][7]. Group 2 - The lifespan of air conditioners is primarily determined by the compressor, and minimizing the frequency of on-off cycles can extend the life of fixed-frequency models [7]. - Variable-frequency air conditioners operate at lower power levels, which can help prolong their lifespan if not frequently turned off and on [7]. - Safety concerns are raised regarding leaving air conditioners running while away from home, particularly if the unit is old or improperly installed, which could lead to fire hazards [8][9].

以下文章来源于果壳 ，作者蓝巾 而且，听说短时间反复开关空调更费电！ 不关吧，家里没人还开着空调，多少是有点浪费钱了！ 果壳 . 科学和技术，是我们和这个世界对话所用的语言。 出门一小会儿，关不关空调？ 文 ｜ 蓝巾 编辑 ｜ 李小葵 来源｜ 果壳（ID： Guokr42） 封面来源 ｜ 视觉中国 你瘫在家里，舒服地吹着空调，突然得出门一会儿。掐指一算： 就出门两三个小时，这空调，关还是不关？ 关吧，那回来后家里很热哎！ 所以，到底怎样做才省钱啊？！ 先算算电费吧 以下结论建立在这些前提下： 离家时间为两三个小时左右； 房间保温效果较好； 室内外温差不太大。 空调可以分为定频空调和变频空调 。 定频空调，它的压缩机一会儿开、一会儿关，所以运行功率是一会儿低到可以忽略，一会儿稳定地高，一段时间内的耗电量是恒定的，功率曲线像城墙垛 子。 所以， 你离家开着定频空调，它运行模式不变 ； 你出门关了定频空调、回家后又打开，它运行模式还是一排城墙垛子，额外耗电不会增加太多。 一句话，为了省电费，定频空调，出门就关 。 变频空调，压缩机的功率是可以改变的，是一根曲线：刚启动时耗电多，是一根陡峭向上的曲线；运行一会儿后耗电 ...