Megawatts to BTU (IT) per second conversion calculator shown above calculates how many BTU (IT) per second are in 'X' megawatts (where 'X' is the number of megawatts to convert to BTU (IT) per second). In order to convert a value from megawatts to BTU (IT) per second (from MW to BTU/s) type the number of MW to be converted to BTU/s and then click on the 'convert' button.