10 Best Energy Efficient Air Conditioners to Keep You Cool Without Raising Your Bill

6. Koldfront WAC12001W -- The Two-in-One Powerhouse

Need both cooling and heating? The Koldfront WAC12001W is your all-season MVP. With 12,000 BTUs of cooling power and 11,000 BTUs of heat, this beast is made for larger spaces. It's Energy Star rated, and despite the size, it manages energy usage surprisingly well. Great for year-round use in bigger rooms or basements.