Megawatt hours to terajoules conversion calculator above calculates how many terajoules are in 'X' megawatt hours (where 'X' is the number of megawatt hours to convert to terajoules). In order to convert a value from megawatt hours to terajoules (from MWh to TJ) type the number of MWh to be converted to TJ and then click on the 'convert' button.