I would like to know which kind of cooling will be the most sustainable, that is, will use the least energy and cooling agents. I am considering summers with temperatures in the high 90's (35-37 Celsius), and about 800 square feet of apartment to cool, in two bedrooms and a large living room "slash" dining room and kitchen.
Would it be better to have a central unit cooling everything or 3 window A/C's for the large central room and bedrooms?