Energy Efficiency is a large subject that is taken seriously by buildings especially where there many and large energy loads, electrical loads such as air conditioners, cold rooms, heaters, lighting loads, refrigerators and whole range of them. There are many choices in the market today, where each of these electric loads can consume very low energy (compared to earlier versions) and still provide comfort/service to end customers. For an air conditioner, one may choose 3/4/5/7 Energy Star rated models, and for lighting, one may choose LED/CFL types. When Energy Efficiency is a major goal, it start right from the building design, materials, construction, and insulation to efficient loads and active systems (such as BEMS to make the building “Grid Responsive”). Buildings may be rated as Platinum/Gold/Silver as per US Green Building Council, or simply work towards being “Net Zero” buildings by combining with rooftop-solar/wind.