Annual energy consumption X price of 1kWh = cost
freezer: -18 ～-22C
As a Japanese, I would like to say that Uchimizu is one of good practices to get our surrounding cool without using energy. Uchimizu is sprinkling of water in gardens and streets. There are certain ways to do. When you do Uchimizu, you use recycle water (water was used in kitchen washing foods and so on). It is Japanese traditional practice.
Another way to save energy, is to sleep early and wake up early. Let's try ecological and economical way to survive this heat :)