Average amp hours per day produced under various conditions:
140 Watt, poly 160 Watt, mono 160 Watt, mono
2012 2013 2014
Overall average output per day 53 amp hours 48 amp hours 48 amp hours
Sunny days 69 71 69
Mostly sunny days 50 50 56
Mostly cloudy days 35 37 39
Cloudy days 32 28 20
Avg. Output on days at anchor 62 61 51
Avg. Output when engine was used 43 44 45
(We had more cloudy days at anchor this year)
Min amp hrs for a day 27 28 4
Max amp hrs for a day 74 77 76
Max amps output 10.5 amps 11.5 amps 11.4 amps
This data is intended to provide a general idea of what to expect from the solar panels under various conditions. The two primary variables are the amount of sunshine and the running of the engine (the alternator charges the batteries so the controller shuts the panels down).
The test boat was running a freezer/refrigerator drawing 5 amps running 6 hours a day, LED lighting, laptop computer drawing 4 amps running 3 hours a day, radios drawing 3 amps running 8 hours a day, and instruments and autopilot when under sail and power. When at anchor on a sunny to mostly sunny day our batteries were at full charge by 2 PM so we usually had excess power.