Solar?

[action]

Looking for pics of your solar set-up.....And any info you would like to share about it. I am thinking about it to keep my battery charged up.
Thanks
Jack

[NYCgrrl]

Re: Solar?

Not 'xactly what you are asking for but still on target sorta kinda...

Flexible 136 Watts Solar Panels.

• 68 Watts single model available.
• Green and renewable form of energy.
• Supplies the trailer with a good electrical autonomy.
• Maximises the durability of the battery by contributing to maintain its charge.

Still, still, I say, researching if this factory installed solar system will do all I want. 'Course the fact that the man is having 2nd thoughts between a travel trailer and this manufacturers' line of motorhomes:

http://www.safaricondo.com/en/motorises

gets in my way a bit.

[MacGyver]

Re: Solar?



This is my much coveted 100 watt Renogy solar panel. It's hooked to a small PWM controller which in turn is connected to one of several AGM batteries that I own. In full sunlight, it puts out about 5 amps which easily keeps the battery topped off if I'm not running heavy draw loads like power inverters all day and night. As I mentioned in another thread, I'm in the process of doubling the panels so I can run pretty much anything I want for as long as I want.

[Happy Joe]

Re: Solar?

You are starting on a slippery slope; the typical sequence is to start small and inevitably it grows... and grows (like MacG above)...
Here is my current one, consisting of a couple of trickle charge panels hinged together, a 35 amp hour deep discharge AGM battery and a modified inverter, its made to be easily portable (carryable) while providing limited power for LED lighting and some music.

What would you like to power for how long?

Enjoy!


edit; Version 3 or 4 will use 2, far less portable, 50 watt panels and a minimum of a 100 amp hour (not easy to carry far) battery. I would like a small MPPT controller but will likely have to settle for a PWM controller or cobble up something custom...

[action]

Re: Solar?

Thanks everyone.....I have an agm battery,inverter....Am mostly looking to keep a charged battery for emergency as I camp with me and my dog If my battery in my old Bronco fails I would be able to jump it. May also try a heating pad in cold weather.
Thanks
Jack

[MacGyver]

Re: Solar?

Thanks everyone.....I have an agm battery,inverter....Am mostly looking to keep a charged battery for emergency as I camp with me and my dog If my battery in my old Bronco fails I would be able to jump it. May also try a heating pad in cold weather.
Thanks
Jack

You could easily keep a reserve battery topped off with any decent panel. The more wattage, the better I think would be obvious. But when you talk about running a heating pad from a battery/inverter setup, then you're into some serious power consumption. Heating pads use resistance heat which is basically a controlled short circuit, as in, huge draw from your reserve.

[action]

Re: Solar?

Yea...just kind of thinking out load....I will try a heating pad at home to to see how it goes.
Thanks
Jack

[toedtoes]

Re: Solar?

As MacGyver mentions, the heating pad will change things. If you're just looking for an emergency jumpstart and maybe re-charging a phone, etc., you might just go for something like this:

http://www.amazon.com/gp/product/B01...ilpage_o01_s00

[Happy Joe]

Re: Solar?

Yep! its all about load (and use time)... small load and short times (me) = small set up; bigger load and or longer time = (MacG.) bigger setup.


A heating pad will probably be a large load.


The size of the panel will be greatly influenced by the desired charge rate or interval, the battery capacity and the depth of discharge; remembering that there is a charging inefficiency of up to 30% or more. (I charge (babysit) at 150% of use time, minimum in bright sunlight, since my total panel output closely matches my small load; ~0.67 amps @ ~12 volts).
As the panel size (output) becomes large enough that the panel is no longer trickle charging the battery; using a charge controller is way better than trying to babysit the charge cycle to prevent over charging and possibly damaging the battery (especially sealed batteries, where water cannot be added/replenished) IMO.


Enjoy!

[MacGyver]

Re: Solar?

...using a charge controller is way better than trying to babysit the charge cycle to prevent over charging and possibly damaging the battery...

When you get into panels that are bigger than small trickle chargers, a controller is a must. Larger so-called 12 volt panels put out somewhere around 17 to 20 some volts and that extra voltage could easily damage a battery. Although it's almost counter-intuitive, a panel that heats up in the sun actually loses some efficiency so they're made to put out a bit more juice. If they didn't do that, and just made the panels to peak at 12 volts, they'd never get up enough voltage when they're hot to properly charge a battery.

[Happy Joe]

Re: Solar?

Yep! I agree. Which is why I recommended a charge controller... the cheapies on amazon are quite inexpensive.
Baby sitting a charging battery can be done, but its a PITA... and if a person messes up it could damage the battery, a controller is cheap insurance, IMO.


Enjoy!

[terasec]

Re: Solar?

You could easily keep a reserve battery topped off with any decent panel. The more wattage, the better I think would be obvious. But when you talk about running a heating pad from a battery/inverter setup, then you're into some serious power consumption. Heating pads use resistance heat which is basically a controlled short circuit, as in, huge draw from your reserve.

quick look
appears heating pad doesnt draw that much
.5 amps on 110V
couple heating pads i looked up are 60-65 Watts

[MacGyver]

Re: Solar?

quick look
appears heating pad doesnt draw that much
.5 amps on 110V
couple heating pads i looked up are 60-65 Watts

I think you'd be surprised how quickly a 1/2 amp load can sap a battery, especially since the inverter itself is consuming power and running around 90% efficiency. That and they usually cut out when the voltage drops to somewhere around 10 volts. This is all about why I've gone to two 100-watt panels.

[Happy Joe]

Re: Solar?

For a quick and dirty approximation of the 12 volt amp draw of a 120 volt item multiply the 120 volt amperage by 10 (its not exact and completely ignores the effects of capacitive and inductive loading but like I said its quick). Note; some (especially chinese) specification are heavily fudged/very inaccurate.
... so not including the inverter expect the amp draw to be a bit larger than 5 amps (0.5 x 10).
Over an 8 hour night (5 x 8) this amounts to 40 amp hours.
In order not draw the, hopefully fully charged, battery below 50% (shortens the life) you should have a battery that has a capacity larger than 80 amp hours (100 amp hours would be even better). just for one night.


A first pass approximation of the panel size; over a 8 hour day in full/not cloudy, unobstructed/unshaded with the panel pointed directly at the sun and tracking it;
5 amps (load) times 14 volts (lead acid batteries, charging theory and controllers vary a bit but this is a fair approximate charging voltage) times 150% (for charging inefficiencies)= ~105 watts
So it is possible that a 100 watt panel in sunny (not partly cloudy), completely unshaded conditions could charge your battery (if its 100 amp hour or bigger) enough to keep your pad warm, although this does not allow for a couple of cloudy or partly cloudy days.


I would, in your place actually measure the combined; inverter plus heating pad's amperage draw, refigure based on real world numbers and then go bigger on both the panel and the battery to give yourself a cloudy day cushion... and carry extra blankets.


Experience has shown me that some campsites just do not work with solar (too shady) and that every 45 minutes or hour turning the panel to follow track the sun helps.
I found that my chinese 10 watt panels only really put out about 4 watts (the specs are both heavily fudged and chinese); be careful and investigate the panel in depth before/if/when you buy.
I purchase Renogy panels for my next upgrade, in part due to their customer ratings and have heard good things about Grape Solar, although I haven't tried them.


Enjoy!

[wecamp04]

Re: Solar?

I tried solar but found 95% my camping is in wooded areas ant it was a pain trying to keep finding the sun every little bit so I got a 1200 amp portable power station works for me