Ergs per second to nanowatts conversion calculator shown above calculates how many nanowatts are in 'X' ergs per second (where 'X' is the number of ergs per second to convert to nanowatts). In order to convert a value from ergs per second to nanowatts (from erg/s to nW) simply type the number of erg/s to be converted to nW and then click on the 'convert' button.