(1) By using led or low energy consumption lights.
(2) By using centralised cooling systems .
(3) Teaching students about energy conservation
(4) Minimum usage of artificial cooling methods by using natural sources like winds sunlight etc..
Turn off lights when not in use—lighting accounts for nearly 50% of the electric bill in most schools.  There’s no reason to leave lights on if a room is empty for more than one minute.  (And, yes, this applies to the new energy-efficient fluorescent lights.)Form a student energy patrol to ensure lights are out when rooms are empty (check classrooms, the cafeteria, the auditorium, etc.).Have students make signs and stickers to remind people to turn off the lights when they leave a room.Put light switches where people can find and operate them.Remove unneeded light fixtures near windows, especially in unused corners or along banks of windows.Have students conduct an experiment in classrooms by turning off selected banks of lights and surveying occupancy comfort at different lighting levels (often, occupants prefer working under natural light).Use energy efficient compact fluorescent light bulbs (CFLs) and light-emitting diode (LED) bulbs.Have students calculate the energy savings achieved by:Replacing incandescent light bulbs with CFLsChanging incandescent lights in Exit Signs to light-emitting diode (LED) bulbs