How much solar do I need.

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BruceP

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We plan on full timing starting next spring. We are currently searching for a 40+ 5th wheel but haven't found what we want yet. Since we like getting away from people I was wondering if I can set up a solar power system that will run everything in the 5th wheel. I see lots of talk about running enough for the tv, but I haven't seen any info on setting up to be completely electrically independent for extended time periods. We will also have a back up generator but I would like to avoid using it as much as possible.
 
BruceP said:
Since we like getting away from people I was wondering if I can set up a solar power system that will run everything in the 5th wheel.
What is "everything"? But I think of solar as a way to recharge the house batteries, reduce the 12 volt load a bit during day light, but not really "run" much of anything.

But IAC, the more the better, with a solar controller. How much solar you really need depends on how fast you discharge your house batteries as well as how much sunlight you get into them for the batteries to recharge. But it's still your house batteries that are running your 12 volt house stuff.

-Don-  SSF, CA
 
Howdy BruceP, Don is right, you need to think of your batteries as a fuel tank from which all your electrical items run (except air conditioning).  You have a couple options for filling that fuel tank - generator, solar, wind, shore power, ???

If solar is your choice (it was my choice), you need to perform an energy audit or budget.  That means figuring out how much power you use so how much you need to be able to supply.  Here is my budget, for use as an example:
http://jdfinley.com/energy-audit-dutch-star/

Once you know how much power you need, it is all downhill!! :)

Some solar panels on the roof, a charge controller, a good battery monitor (get this now to help you figure out what you use/need), and you are in business!!

Here's where I am this week http://jdfinley.com/peace-quiet-gunnison-national-forest/- haven't fired up the generator all year (except to circulate the oil).

Edit: Also, I've been amazed to hear recently that many large trailers don't come with batteries or an inverter.  You will need both, obviously.  So, be sure to get an RV that either has them or plenty of space to add (at least 4 big batteries, maybe more).
 
Well since I haven't bought my RV yet, I don't know what everything is. I guess what I'm asking is if I can configure enough solar panels that I can live 'normally' without shore power. I know 'normally' is subjective but lights and tv on demand are something that is important to the War Dept.I guess a residential refer would be out of the question for boondocking, or will they run off the batteries. I know that once I get closer to the purchase we will be able to pin down how much power it will take.

How does one run the AC while boondocking? Is that one of the things that must be sacrificed when away from shore power.?

I want to have all the solar panels installed when I make the purchase and do not want to rely on the sales guy or the seller for advice on what I will need.
 
If you want to make sure you know and understand solar power systems read these two blogs, and reread them until you fully understand them, then you will know what you want and need.

https://handybobsolar.wordpress.com/

http://www.jackdanmayer.com/rv_electrical_and_solar.htm
 
BruceP said:
Well since I haven't bought my RV yet, I don't know what everything is. I guess what I'm asking is if I can configure enough solar panels that I can live 'normally' without shore power.

Yes, it is possible.  Read at the energy budget link I sent and you will see what I run (and how I live) using solar.  I am a full-timer and solar provides all my power.

BruceP said:
I guess a residential refer would be out of the question for boondocking, or will they run off the batteries.

That is possible as well. Several guys here are doing it.  A residential refrigerator requires 120 VAC power.  An inverter "changes" 12 VDC power to 120 VAC power.  You just need an appropriate inverter and sufficient battery bank capacity to make it work.

BruceP said:
How does one run the AC while boondocking? Is that one of the things that must be sacrificed when away from shore power.?

You either run the generator or you install a sufficiently sized battery bank and inverter.  This is really not "reasonable" (size and weight) with lead acid batteries.  I know a few of the folks running lithium batteries are able to run the air conditioning.  However; the lithium investment is large (think $10k).  If that doesn't shock you, the lithium world is very interesting and worth exploring.
 
BruceP said:
How does one run the AC while boondocking? Is that one of the things that must be sacrificed when away from shore power.?
You will have to run the generator, making sure the exhaust from it cannot get inside where there is anything living. There are extender pipes you can buy to bring the generator exhaust to above your roof.

When you main vehicle fuel tank gets down to around a quarter full, the generator will run out of gas.

-Don-  SSF, CA
 
How much solar and battery capacity you'll need will depend on your usage, and when and where you camp. Our coach is as power-hungry as they come. With a large residential fridge, three entertainment centers, a 12 cup A/C coffee maker and large microwave oven, all of which operate off the 2800 watt inverter, we consume a relatively high amount of power. We love to boondock, so we wanted to determine if we could install enough solar to replenish all the power we use in a 24 hour period.

I ended up buying a Kill-O-Watt meter to measure our coach's AC power consumption, and a Trimetric battery-monitor that measures exactly how many amps are going into, or out of, the house-batteries at any given time. I won't bore you with all the numbers, but in the end, we needed 800 Amp Hours of battery capacity, and 900 watts of flat-mounted solar panels to fully recharge our batteries on a sunny, winter So Cal day. We ended up with 970 watts of solar and 840 AH of battery capacity, but even so - if it's a cloudy day, we're going to have to run the generator.

As long as the sun shines, we don't need to run our generator at all... unless... we want to run an air conditioner. It's just not practical to run a 13000/15000 btu AC unit off battery power. Fortunately, in the winter, we usually don't need air conditioning. Keep this in mind about boondocking - power is just one limiting factor, holding tank capacities are another. Most people fill up their gray water tank first. Running out of fresh water usually means breaking camp, and as I've always said, "The party is over when the black tank is full."

Kev
 
Kevin has given you great solar info, as he always does. So I will just say that our setup is just about exactly the same as his and works very well.
 
Paul & Ann said:
If you want to make sure you know and understand solar power systems read these two blogs, and reread them until you fully understand them, then you will know what you want and need.

https://handybobsolar.wordpress.com/

http://www.jackdanmayer.com/rv_electrical_and_solar.htm

Yelp, read the bibles a few times.  Don't spend any money on solar until you've camped enough to understand your needs. 

Joel
 
Yes you can live normally for extended periods and not be connected to shore power.

This summer we boondocked and dry camped for 139 days (4 1/2 months) on our Alaska trip and only ran our generator for about 1.5 hours to charge our batteries. We had 3 days of very cloudy weather.  We did exercise the generator once a month as required for generator maintenance but that was not needed to recharge the batteries. 

This is our daily energy comsumption:
-- A TV (flat panel LED) and a satellite TV receiver for several hours each day
-- Microwave as needed up to 15-30 minutes usage each day.  We did not attempt to use the microwave/convection oven to cook for hours as that is like trying to run the AC.  You need far to much battery and solar capacity for that.
-- 2 laptops for several hours a day. 
-- My wife's CPAP (breathing machine) every night
-- Lights in the evening (all lights that we have on for any long period of time have been switched to LED)
-- Recharging my wife's electric scooter and/or power wheel chair as needed. 
-- toaster at breakfast
-- a 12V chair lift to get my wife in and out of the RV. 

We use about 100-150 AH (Amp Hours) each day.

We have 650 watts of solar in two large panels, 400 AH of lithium battery which gives us over 300AH of usable capacity, a 2000 watt inverter to operate all the 120V appliances and a solar controller to control the charging of the batteries from the solar panels.

We use lithium because of weight and increased usable capacity for the size.  To use AGM batteries and get the extended life from the AGM batteries we would need about 800AH of AGM.  That would be 8 batteries with a total weight of about 640 pounds.  Our lithium batteries weight 130 pounds.
 
Here is a list of links for more reading about RV power and Solar:

http://www.rv-dreams.com/rv-electrical.html
http://www.jackdanmayer.com/rv_electrical_and_solar.htm
http://www.jackdanmayer.com/Batteries_and_charging.html
http://www.marxrv.com/12volt/12volt.htm
http://www.marxrv.com/12volt/12volta.htm
http://www.wholesalesolar.com/deep-cycle-battery-info.html
http://www.batteryfaq.org/
http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/
 

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