What is "add noise" also on the hydrogen load screen?

I'm using the same window for the hydrogen load that we use for the primary electrical load and the thermal load.  In all cases, to synthesize an hourly data set you define one or more daily load profiles and then specify how much "noise" or randomness you want HOMER to add to those load profiles.  If you add no noise, then the hourly data set will consist of the daily profile repeated over and over, with no difference from day to day.  With noise, their is some random variation from hour to hour and day to day.  There's more info in the HOMER help file -- look up "noise in load data" in the index.