Wireless sensors can help reduce energy bills by controlling electrical switches and devices without wiring. The sensors use wireless communication to transmit signals to actuator nodes behind switches. This allows single sensors to control multiple switches and devices located in different areas. Wireless sensors provide benefits like easy installation within an hour without disrupting operations, maintaining aesthetics by eliminating wires, and variable control of different devices. They are suited for situations with intermittent occupancy like offices, classrooms, and warehouses.