A roadway deicing system uses a pressurized gas stored in a high pressure tank to dispense a solid or liquid deicer onto a roadway. An electrically powered controller responds to control inputs to control valves, such as solenoid valves, to cause the deicer to be dispensed at appropriate times. Since electrical power is not used for propelling the deicer onto the roadway, conventional storage batteries can provide long service life for the system between maintenance intervals.