Enough Solar for conservative boondocking?
Hey Guys, I looked for the "Dumb Questions" thread, but didn't see it, so I'll post my question here. I want to be able to boondock for 3-4 nights with my family of five on our 28 foot TT. I don't p...
Forum Discussion
The question is how much power will you get out of that 100 watt solar panel, particularly in the cooler months with shorter days. How many clouds will there be when you go camping, and will the rv site be shaded by trees, etc.
Under ideal conditions a fixed mount 100 watt solar panels will provide about 600 watts of total electricity per day. Given things are seldom ideal, charge losses, etc. you can expect a real world average output to be closer to 400 watts at the battery.
You don't specify your running loads, but lets assume the control circuit for your refrigerator uses 10 watts (about average for a Dometic refrigerator, though some have a defrost bypass switch that lets you cut that in half while dry camping) 10 watts x 24 hours per day is 240 watts just to run the refrigerator control board. LED lighting will be trivial in comparison (a 60 watt incandescent bulb LED equivalent will draw only 7 watts), assuming you run 1 of these 7 watt LED bulbs for 4 hours per day, that is only 28 watts. The water pump will be a similar low draw, due to its limited run time, and your limited amount of onboard water, a typical 3GPM water pump will draw about 7.5 amps running (90 watts) however it can also empty a 45 gallon water tank in 15 minutes, consuming less than 25 watts total to do so.
So far out of 400 watts available per day form a 100 watt solar panel we are at
Refrigerator 240 watts
LED lighting 28 watts
water pump 25 watts max
For the furnace, it depends what you have, the Suburban SFQ series draws about 7 amps while running, vs the NTQ series draws about half that. Lets assume you have an SFQ series, 7 amps at 12V is 84 watts. Assuming 15 minute per hour run time, and 10 hours per night of use, you are looking at needing 21 watts per hour or 210 watts per night for the furnace.
Putting your total at just over 500 watts per day with the propane refrigerator being the biggest power draw.
Now in practical terms, real world conditions (clouds), you really should consider a minimum of 250 watts of solar panels and 2 deep cycle batteries for extended dry camping. Since no matter what you do it is hard to shave much off of that refrigerator and furnace power draw.
Under ideal conditions a fixed mount 100 watt solar panels will provide about 600 watts of total electricity per day. Given things are seldom ideal, charge losses, etc. you can expect a real world average output to be closer to 400 watts at the battery.
You don't specify your running loads, but lets assume the control circuit for your refrigerator uses 10 watts (about average for a Dometic refrigerator, though some have a defrost bypass switch that lets you cut that in half while dry camping) 10 watts x 24 hours per day is 240 watts just to run the refrigerator control board. LED lighting will be trivial in comparison (a 60 watt incandescent bulb LED equivalent will draw only 7 watts), assuming you run 1 of these 7 watt LED bulbs for 4 hours per day, that is only 28 watts. The water pump will be a similar low draw, due to its limited run time, and your limited amount of onboard water, a typical 3GPM water pump will draw about 7.5 amps running (90 watts) however it can also empty a 45 gallon water tank in 15 minutes, consuming less than 25 watts total to do so.
So far out of 400 watts available per day form a 100 watt solar panel we are at
Refrigerator 240 watts
LED lighting 28 watts
water pump 25 watts max
For the furnace, it depends what you have, the Suburban SFQ series draws about 7 amps while running, vs the NTQ series draws about half that. Lets assume you have an SFQ series, 7 amps at 12V is 84 watts. Assuming 15 minute per hour run time, and 10 hours per night of use, you are looking at needing 21 watts per hour or 210 watts per night for the furnace.
Putting your total at just over 500 watts per day with the propane refrigerator being the biggest power draw.
Now in practical terms, real world conditions (clouds), you really should consider a minimum of 250 watts of solar panels and 2 deep cycle batteries for extended dry camping. Since no matter what you do it is hard to shave much off of that refrigerator and furnace power draw.
