Most Trane air conditioning systems are energy efficient. As of February 2015, 12 out of 13 of Trane's air conditioners qualify for the Energy Star program, which requires air conditioners to meet energy-efficiency standards put in place by the U.S. Environmental Protection Agency.
Air conditioners have a Seasonal Energy Efficiency Rating, or SEER, that indicates how efficient the unit is. A SEER of 14.5 or higher qualifies a unit for the Energy Star program. Trane's most inexpensive air conditioner, the XB300, has a SEER of up to 13. Every other Trane air conditioner has at least a 14.5, and the XV20i Variable Speed has a SEER of up to 21. The XV20i is one of the most efficient air conditioners available as of 2015 and can reduce annual power costs by up to 60 percent, depending on the system it is replacing. Trane also offers programmable thermostats that reduce energy usage by accurately controlling the temperature.
SEERs are listed as "up to" a specific number because external factors can affect the unit's efficiency after installation. Issues that can lower a unit's efficiency include improper air flow and leaking air ducts. Correct installation of the air conditioner minimizes these issues. Certain Trane products are equipped with the Trane ComfortLink Communicating System, which allows components of the air conditioning system to communicate with each other and self diagnose issues to maintain efficiency.