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Topic: Solar Panel Education 101- Question (Read 12 times) previous topic - next topic
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Solar Panel Education 101- Question
Yahoo Message Number: 157923
The two (2) factory installed 100 watt solar panels on our LD are the first time we have had solar power anything (at least as far as I can remember).  I've done some online reading, but after a short time I get a little lost.  At any rate, how much energy should we expect from 200 watts of solar power on a clear and sunny day? We still need to study our daily boondocking power usage, which is my homework sometime next week.  At any rate, thanks in advance for this help

Ed & Margee Fort Worth
Re: Solar Panel Education 101- Question
Reply #2 –
Yahoo Message Number: 157925
Thank you Chris.  That was a nice summary.  So it looks like each 100 Watt panel could produce ...  "an average of about 6 amps per peak sun hour, or about 30 amp-hours per day."  So we'd be looking at 60 amp-hours more or less on a sunny day.  I'm guessing we'd use more than 60 amp-hours especially if we use the propane heater on really cold days and nights.

Ed & Margee Fort Worth
Re: Solar Panel Education 101- Question
Reply #3 –
Yahoo Message Number: 157926
You are welcome. Yes, the propane heater (furnace) is an amp hog. As you probably have read here many times, a catalytic heater is a welcome addition to boondocking and seriously reduces use of the propane heater.

Chris
Formerly: 2002 30' IB
Re: Solar Panel Education 101- Question
Reply #4 –
Yahoo Message Number: 157927
Remember that, in addition to how many panels you have, the time of year has everything to do with it. I can only give you performance from our home system here in north/central Arizona. The peak months of the year are April, May and June. The months before and after show a steep incline or decline. Our 4,000 KW system can only produce that in those three months. Here at the start of the new year 2,500 watts is about the best we can do. And that's on a clear, sunny day. So figure about a 35% reduction in power if you are camping in the winter. When it clouds up it's over. I have seen our 4,000 watt system producing only 60 watts.

Dick
 
Re: Solar Panel Education 101- Question
Reply #5 –
Yahoo Message Number: 157928
" So it looks like each 100 Watt panel could produce ... "an average of about 6 amps per peak sun hour, or about 30 amp-hours per day."

You might get that much in the middle the summer but expect half that much in mid-December.
Shadows get long in the winter and keeping out of them can be difficult.

Without a battery capacity meter, you have no idea if the battery is being charged or discharged or what the present charge level is. It is very important not to use more the 50% of the battery's capacity regularly.
With the stock battery, about 110-amps hours is available for use.

If you boon dock in cold places, where the furnace is used a lot, you will probably need to supplement the  solar with the generator, for battery charging.  If your LD is more than a year or two old, better converters are available that can significantly reduce generator run times.

Most LD roof's have room for 400-watts of solar or more.
If you have room, add two more AGM batteries (assuming the Factory batterie are AGMs).
Either way, it requires buying four new batteries. It does double the amount of useable amp-hours and prolong the times between generator runs. It also allow the use of the largest chargers available, when the wiring is upgraded.

Efficient use of 12-volt power is as important as solar.
Save your battery and propane by getting a Wave heater, for daytime use.
Get a thick comforter for cold nights.
Electronics can use a lot of power, make sure your's are not power hogs and are turned off when not in use.
12-volt chargers are usually more efficient than using an inverter and 120-VAC chargers.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze