Gigawatts to BTU (IT) per hour conversion calculator shown above calculates how many BTU (IT) per hour are in 'X' gigawatts (where 'X' is the number of gigawatts to convert to BTU (IT) per hour). In order to convert a value from gigawatts to BTU (IT) per hour (from GW to BTU/h) just type the number of GW to be converted to BTU/h and then click on the 'convert' button.