Some are more obvious than others,examples would be solar energy in newly built buildings (maximising the sun in relation to building design, heating and power supply).More efficient mining equipment(electric over diesel)Pressure sensitive pads in hall ways store rooms etc. to turn lights on for a certain amount of time,auto lights off after a certain time,computers turned off and not in hibernation when finishing of a day,energy efficient light bulbs,recycling of paper waste etc...Specific areas in fixed plant environments for lights on(major walkways and high traffic areas.)
Sorry I can keep going and going.The minesite I am on are currently doing this and much more