The Bureau of Energy Efficiency (BEE) has a grading system called Energy Efficiency Ratio (EER). This is meant for home appliances such as air conditioners, inverter air conditioners, RAC (Cassette, Floor Standing Tower, Ceiling, Corner AC), frost free and direct cool refrigerators and other electrical equipment. Air conditioners are rated in BTU (short for British Thermal Unit) regardless of their capacities and tonnage. BEE Registration at Corpseed ITES Pvt. Ltd.