Looking for a 40 amp MPPT solar charge controller

Hi Niner,

You have not allowed for the greater atmospheric path. On December 21st, in perfect solar conditions, I get 17 amp hours from 256 watts of panels during 8 hours of sunlight. In June I get over 100 amp-hours. My guess is that I'd need 5X the panel wattage for my location which is about 51 degrees latitude.

NinerBikes wrote:
with short days and northern lattitudes, you may need a factor of 2 or 3x the watts to amp hour ratio that most consider normal, ie 1 watt of panel to 1 amp hr of battery.