Ergs per hour to milliwatts conversion calculator above calculates how many milliwatts are in 'X' ergs per hour (where 'X' is the number of ergs per hour to convert to milliwatts). In order to convert a value from ergs per hour to milliwatts (from erg/h to mW) just type the number of erg/h to be converted to mW and then click on the 'convert' button.