How we can minimize the electrical energy consumption in day to day use of electrical and HVAC equipment?

In electrical use capacitors in the main line, Also use capacitors in fluorescent lamps. Use LED lamps. Use proper size wire so that we can reduce voltage drop. Avoid loose connections. Switch off lights fan and other equipment when we are not required that. 

In HVAC keep all the ventilation and doors are closed always. Use curtains in the glass windows. Avoid heat producing lights inside AC rooms. Switch off the AC when we are not required.

By using capacitors ,energy efficient motor,

By using energy saver lamps, LED lamps & use of proper illumination

For HVAC Equipments proper design calculations & Power capacitors to be selected so that you can save energy consumption