How much solar power needed for?

[icanon]

Hey everyone! I do a lot of astronomy and planning to go on the four day 'off grid' trip. I'm wondering how much solar power do I need? Basically just need to keep my 12V RV battery charged. I just need the battery to keep the propane fridge, water heater running and water pump to shower with (no microwave, a/c, or TV). So how much of a solar power kit do I need?

Thanks. 🙂

[EsoxLucius]

Not likely.

[icanon]

Again thanks for all the replies and info.

I'm going to add a second battery and (thanks to my neighbour) try the 40W solar and see how it works out. Should be OK?

[TucsonJim]

icanon wrote:
Thanks all for the quick replies! Thinking about adding a second battery and a solar portable.

Was just talking to my neighbour and mentioned I was thinking about solar power, next minute she goes in her garage and brings out a new 'in the box' 40w solar portable and hands it to me and says it's yours.

So Question: Can I 'chain' link a second 60w (or more)panel?

Thanks again for your replies.

It depends on how much the charge controller will handle. My son uses a 40 watt charger, and has similar usage to you. He can camp for a week or more and never needs to charge his batteries as long as he points the panel at the sun all day.

Jim

[MrWizard]

for twice a year ?
i would stick with a small generator and a good automotive battery charger
like the 40amp vector

[icanon]

Thanks all for the quick replies! Thinking about adding a second battery and a solar portable.

Was just talking to my neighbour and mentioned I was thinking about solar power, next minute she goes in her garage and brings out a new 'in the box' 40w solar portable and hands it to me and says it's yours.

So Question: Can I 'chain' link a second 60w (or more)panel?

Thanks again for your replies.

[MEXICOWANDERER]

Carry a couple extra batteries

WAY CHEAPER

Than panels, mounting, controller and wire. If this is a 1-shot deal recharge the batteries when you get home then sell them at a -25 dollar loss on Craigs List. Fifty bucks no hassles and you're home free.

[JiminDenver]

Just four days? You should be able to get through that with the use you describe on a decent, well charged battery. A extra battery and LED lighting would be a good start. Otherwise a 100w portable would easily keep up with the limited use.

[Helimech]

100 watts and keep it pointed to the sun and that should do the trick.

[TucsonJim]

I have two 100 watt panels and similar usage as you. The two panels are overkill. I'm usually fully charged in 3-4 hours of sunlight. For your use, I'd probably go with a single 100watt panel.

[fitznj]

I have a ~150W solar panel and 2 Walmart batteries; Keep me going almost indefinitely. I have not camped during the winter yet with this set up.

I have digital voltmeter hooked up to the battery and can keep a constant eye on the state of the batteries. My batteries charge even on an overcast day (like today in NJ) - but not as efficiently.

Gerry

[2oldman]

icanon wrote:
I want to go as cheap as possible.

Everyone does. One 120w panel will be fine.

Seriously, twice a year, 4 days.. go real cheap and just carry a spare battery. Your usage is close to nothing, unless it gets cold and you need furnace.

[icanon]

smkettner wrote:
Depends on conservation. You could make four days fine if you turn nothing on.
I will suggest two batteries and 200 watts to get started.
Will also depend on getting a sunny campsite.

I just need it to keep the propane fridge, water heater running and water pump to shower with.

[time2roll]

Depends on conservation. You could make four days fine if you turn nothing on.
I will suggest two batteries and 200 watts to get started.
Will also depend on getting a sunny campsite.

[icanon]

Happy Prospector wrote:
How much money do you have for this project?

I want to go as cheap as possible, it's only to be used maybe twice a year the rest of the time I'm camped with full service.

[Happy_Prospecto]

How much money do you have for this project?