solar panels VS batteries

[dreadcptflint]

ok I 've been trying to understand the whole solar movement and I am wanting to know is it better to have more batteries so that you have a reserve supply of power or is it better to have more panels to meet the demands and have the batteries fully charged or is it better to have an equal amount of both?

It all depends on what your needs are. My wife prefers to have us camp in the trees which means big shadows on my panel. I went as big as I could fit on my roof for that reason. In almost every location and in every situation, I have gotten power from my panel to my battery.

Now the big factor that I practice is don't be a power hog. I don't try to run an AC unit or every piece of electronics known to man kind. I am reasonable, my CPAP, a few lights and a water pump. Most mornings I am charged before 11:00 am. This is an 4 year plus deep cycle battery.

I view electrical as an building with more stories equaling the more power that you want to use. A solar panel is like taking the stairs, it's good for you and as long as you don't climb too many then it is not too difficult. A gas generator is like taking an elevator, it can easily get you to the top of the building but sometimes there are strange smells involved.

[droid_ca]

so I checked out that site and it said under the rv section that there should be 85 watt panel and a 110 ah battery per person, just curious how many follow this rule or is it a gimmick to sell more?

[Ratkity]

so I checked out that site and it said under the rv section that there should be 85 watt panel and a 110 ah battery per person, just curious how many follow this rule or is it a gimmick to sell more?

Interesting that the site said that. I've never read it before. Just added up needs and then figured the 60W diy panel of bruce's was probably my minimum (and was about to do this setup). The prices dropped significantly on 85W panels at u-solar and I opted for one of those.

I guess I just fit da profile!

Hugs,
Ratkity

[bdosborn]

so I checked out that site and it said under the rv section that there should be 85 watt panel and a 110 ah battery per person, just curious how many follow this rule or is it a gimmick to sell more?

That applies to a full size RV rather than a tear. Start adding in inverter use for a microwave, full size TV, stereo, etc. and your energy usage skyrockets. That's why its important to do an inventory of your devices. What did you end up with for your usage?

Bruce

[droid_ca]

with all the bells and whistles 912

[bdosborn]

with all the bells and whistles 912

Hmm, are you sure you got that number right ? Your battery is going to weigh more than your trailer. I would expect something like this:

LED Lights 0.5A X 4 hours
Water Pump 5A X .25 hrs
DVD player 5A X 2 hours
Stereo 2A X 2 hrs

Total=17.5 amp-hrs

3 days would be 52 amp-hrs so a group 27 at 105 amp-hrs should be about right. I use 3 days for battery capacity because that's a Friday, Saturday and Sunday; which is what most of our camping is.

Group 27 Linky
Bruce

[droid_ca]

so my second guess is 192.8

[bdosborn]

I wouldn't bother with a PV panel and a battery with that kind of usage. Either plug in to shore power or buy a generator...

Bruce

[droid_ca]

I still must be adding wrong

[droid_ca]

hahaha I figured what I was doing wrong my old calculations I had pumps and lights going for 24 hours OOPS so the corect numbers now would be 36 per day so over a three day stretch 108 now thats better

[bdosborn]

I still think that's high but its manageable with 2 golf cart batteries and 220 watts worth of PV panels. That's the size of my system but I typically only use around 20 amp-hrs in a night.





Bruce