Want to install solar, questions
We recently got our new 2017 Nexus Ghost and I had it pre wired for solar. Nexus provided (in a box) a Zamp 30 amp Digital Controller with the pre wire. My question is how many 100watt paneles well...
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roof panels have one downside for most uses. the optimum tilt angle for getting rated power needs to be about the latitude your at plus solar declination. That means something around 45-60 degrees tilt. depending on location and time of year. If they are If they are laying flat and you need 45 degrees tilt, max power out of the panel is about 70 percent of the panel rating, at 60 degrees, max power is around 50 percent of panel rating.
the derating is the cosine of the angle error you have.
Now if the panels are portable and you can adjust the angle, 500 watts in parallel should get you close to 30A.
But then how many amps hours do you need to replenish each day. assuming 6 hours of sun, and 20 amps average output you'd put 120AH back into the batteries. That's a pretty healthy amount.
We dry camp a lot, use a cpap, furnace, fans etc and my typical daily use is at most 100 AH out of a 500AH bank. A 15A MPPT controller with 240 Watts of portable panels will keep me charged up if I have good sun for about 8 hours during the day with the panels angled correctly and pointed south.
So, for roof mount with a 30A controller you may need 500 or more watts to get what you need.
but the downside to portable panels is storage and the opportunity for them to gain legs.
But then we often camp in the shade and one of my favorite spots needs about 100 ft of cable to get the panels in the sun. That pretty much dictates series panels to keep IR loss down and MPPT controller.
the derating is the cosine of the angle error you have.
Now if the panels are portable and you can adjust the angle, 500 watts in parallel should get you close to 30A.
But then how many amps hours do you need to replenish each day. assuming 6 hours of sun, and 20 amps average output you'd put 120AH back into the batteries. That's a pretty healthy amount.
We dry camp a lot, use a cpap, furnace, fans etc and my typical daily use is at most 100 AH out of a 500AH bank. A 15A MPPT controller with 240 Watts of portable panels will keep me charged up if I have good sun for about 8 hours during the day with the panels angled correctly and pointed south.
So, for roof mount with a 30A controller you may need 500 or more watts to get what you need.
but the downside to portable panels is storage and the opportunity for them to gain legs.
But then we often camp in the shade and one of my favorite spots needs about 100 ft of cable to get the panels in the sun. That pretty much dictates series panels to keep IR loss down and MPPT controller.
