We tested our new 150 watt polycrystalline solar panel on a 35 day cruise in the North Channel area of Northern Lake Huron. This panel was equipped with the prototype of our solar water heating system which will be addressed in another blog entry. The solar panel was mounted on our pole mounting system and was rotated toward the sun The boat equipment and cruising pattern was essentially the same as last year (See prior blog entries). We were powering a freezer/refrigeration system, instruments, laptop computer, radios, autopilot, windlass and LED lights. Data was gathered using the remote display on our EP 10 amp dual output solar controller. The solar panel performance met our expectations. Our house battery bank consists of three 120 amp hour flooded batteries.
Both battery banks were usually fully charged by 2 PM when at anchor and on mostly sunny days so we often had excess power.
Data comparing the performance of the 150 watt solar panel with our 140 and 160 watt panels is presented below.
Average amp hours per day produced under various conditions:
150 Watt poly 140 Watt, poly 160 Watt, mono 160 Watt, mono
2015 2012 2013 2014
Overall average output per day 49 amp hours 53 amp hours 48 amp hours 48 amp hours
Sunny days 60 69 71 69
Mostly sunny days 56 50 50 56
Mostly cloudy days 36 35 37 39
Cloudy days 22 32 28 20
Avg. Output on days at anchor 60 62 61 51
Avg. Output when engine was used 42 43 44 45
Min amp hrs for a day 4 27 28 4
Max amp hrs for a day 84 74 77 76
Max amps output 11.8 amps 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 off power from the panels). Because the panel was equipped with a water heat collector on the back, it may have run hotter on sunny days when the water circulation pump wasn't run thus degrading the performance by up to 10%.The average panel output on sunny days at anchor with no motoring was 67 amp hours.
Thomas Trimmer has been cruising with his Ericson 38 sailboat on the Great Lakes for over 20 years. He has pioneered the use of solar energy for wilderness cruising. He is continually designing and building equipment to simplify and enhance the cruising experience.