First Published: January 23, 2010 | Last Updated:January 23, 2010
Its a measure of Heat Energy. One British Thermal Unit or BTU is a traditional unit of energy equal to about 1.06 kilojoules. One MBTU is 1000 BTU. One MMBTU is 1 million BTU i.e. 1000 X 1000 BTU. 1 MMBTU is called a Therm.