In an effort to save money and energy, many homeowners are purchasing AC units with programmable thermostats. Energy Star provides a savings calculator to determine how much money you can save by owning a programmable thermostat with your air conditioning system.
The calculator asks about the number of units in your home, 24 hour typical usage patterns, annual and life cycle costs for 1 programmable thermostat, and it gives you a summary of benefits which includes the initial cost difference, life cycle savings, air pollution reduction equivalence, as well as savings as a percent of retail price.