270w solar world panels

Yes, one can go for a week without any solar, if battery bank is big and daily energy needs are very low. You can even go for a month without any sources of power supply other than AA/AAA batteries. Did this a number of times myself. What the OP can or want do, - we don't know.

KNOW THY NEEDS.

BFL sure does - that is, he needs no solar ;) - because his energy needs, on one hand, and location, on the other hand, make living on solar very difficult.

Energy audit is the first step with any serious solar planning. What do you want from solar system? How much energy can you live on? Can solar reliably supply this, or you needs are so high and the weather is so dark that there is no chance to have a sustainable solar? And so on. To keep batteries charged between the trips a single 100W panel could be enough, or a 120V charger, or both.

Other things to consider are whether you want/need a permanent install, or a more portable one; do you park in the sun or the shade; do you require air conditioning, and other high draws? Lots to consider.

Check out the other solar threads here. Lots of good info.

Each battery will store about 1,000 watts if you plan on discharging them to less than 25%. As a practical measure, only discharging them to about 50%, then you will have only about 100 'useful' amp hours, or 1,200 watts total with only 2 batteries. 4 batteries is 2,400 watts. I had 4 batteries, but now only carry 2 - saving weight. I don't do as much dry camping and my 400 watt solar system fills it daily.

I used to use upwards of 120 amp hours each night, and still was able to recharge in the day. My RV uses 35 amp hours daily just to run the CO meter, propane detector and refrigerator. Anything else is lights, pump, and mostly TV set and Satellite receiver.

Good luck,

Fred.

You shouldn't buy them just because it's a good price but rather do you need/want them? I'm in the process of installing 3 250W panels that are the same dimensions. Plus MS MPPT 60 controller ($472), remote ($102) and other equipment. Many on these boards started with smaller systems and some keep expanding. But I researched and planed for some time and now I'm installing the system.

Make a cardboard pattern and see where it fits on the roof AND shadows on the panels are BIG power reducers.

A great many RVers can already go out for a week without any solar.
A week is no big deal. Let's tell the OP the truth and not spend all HIS money on OUR pet things.

BFL13 wrote:
The OP wants to stay out for a week, so all he needs is enough solar to help the batteries get by that long at his usage. Then he can go home and do a full recharge. IMO that would be say, a 130w panel...

Since they didn't specify their energy needs, we can only guess how much solar they need. They said "enough to run all my essentials", which can be anywhere from 20 to 200 AH a day.

A 130W panel on a dark day will collect 5 or 7 AH, it's difficult to keep batteries full with that little energy, even for a die-hard minimalist. So the charge will drop lower and lower every day if such a dark spell continues. Depending on their daily energy needs, with 2*6V they might be out of juice the very next day or 2 days later. Or batteries will be losing 5-10% every day, eventually reaching 40-50% by day 7 - you know well what this means for batteries.

A 2*270W will collect 30-35 AH under the same conditions, this is something that one could live on already.

500+ watt is not a "giant" anymore, get over it :)

The OP wants to stay out for a week, so all he needs is enough solar to help the batteries get by that long at his usage. Then he can go home and do a full recharge. IMO that would be say, a 130w panel and a $15 eBay PWM controller.

IMO forget the giant expensive solar set up unless staying off grid for weeks and weeks at a time.

Almot, the OP's daily needs may not even warrant an expensive 540w, 24v system.

Besides, I'm not out to confuse anyone, only make them aware of the questions they may have to ask themselves... just like I've had to do.

Brian, what do you figure will be your daily usage in Amp Hours? This is where you must start, when sizing a battery bank, as well as solar.

Do we really need to confuse the OP any more than he already is? :)

Mono vs poly is a minor difference, though poly is usually slightly better.

Advantages and disadvantages of PWM vs MPP become purely academic with installs over 500W since there are no PWM in this range.