2 way styles for dispenser: Electric and air pump without using electricity;Choices of Energy saving modes: VE mode & Energy Saving Mode;VE Mode is when the water boils, heater shuts off automatically and uses Stainless Steel Vacuum Insulation to keep warm;Energy Saving Mode applies after 2 houes not in use; It reduces approximately 9F from regualr setting temperature;Auto lock system after dispensing for safety