An access control system having an energy-saving optical presence sensor system is provided. The access control system includes a relatively lower operating power object presence sensor system for optically sensing the presence of a token as well in addition to a relatively higher operating power token reader for reading the token. The token reader remains unpowered until a token is detected by the object presence sensor system, which is preferably always powered. Once an object is detected by the object presence sensor system, power is supplied to the token reader and the token is read. After the token has been read, power ceases to be applied to the token reader, although the object presence sensor remains powered.