The Most Expensive AC Setting to Use During a Heat Wave, Experts Say - marthastewart.com

Trying to stay cool during a heat wave? Experts reveal the AC setting that can drive up energy costs the most—and what to use instead to save money.

Running your AC during the warmest days of summer offers a reprieve from the heat, but you may be worried about the energy costs of keeping your home cool for weeks at a time. If your energy bill sky…