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Solar panel questions

smokeyyank

NAXJA Forum User
Howdy all,

I've been searching and haven't been able to come up with a whole lot so I'm hoping someone can point me in the right direction. In my scramble to get some last minute stuff in place before camping and wheeling season I was wondering about adding a solar panel to my rig. Basically what I am looking for is having the ability to charge a cell phone, my blue tooth speaker and possibly power tools if needed when I’m offroad . Would I just be able to use a trickle charger hooked up the battery when the rig is off the not drain the battery or is there another way? Also I’m pretty sure I would need a power inverter any suggestions on that? Thanks again.
 
You can get a solar trickle charger, in the RV department of your local ACE hardware for about $25. This kind is portable and if you're parked in a campground you just plop it on your hood, hook it to your battery, and charge your phone through a power outlet, also available at ACE, hard wired to the battery with a USB charger port. With the combo of the charger and a power out let, you don't have to turn on the Jeep. The sun does all the work. Really no need to "mount" it to your Jeep. The $25 type are NOT weather proof

Disclaimer: I do not work at or have any financial interest in ACE hardware.
 
You can attach the trickle charger directly to the battery. They are designed and built that way. But don't expect to get enough power from it. That's why it's called a trickle charger.

If you want a true solar package, you will need a battery, a solar panel, and a charge controller.

The battery: Most likely the battery you already have in your rig. A lot of off roaders who spend extended times off grid will have at least one more battery hooked into the system.

Solar Panel: Solar panels come in a HUGE assortment of sizes, configurations, and output. My only advice is buy mono-chrystaline panels not poly. Buy the largest output panel that you can afford and are willing to cart around with you. Like most things, the more power you expect from it, the larger it will be physically. I have 3 (older) 15 watt panels equalling 45 watts on my RV. With a wife, 2 kids, and 2 house (marine) batteries, it's barely half of what I need. Maybe a third. It's almost impossible to get TOO much power from a mobile set-up. And remember the numbers the manufacturers give you for their panels is under IDEAL conditions. Things like clouds, shade, indirect sunlight, even too much dust will reduce the efficiency of the panel. My 45 watt panels on a good day will be lucky to produce 30 watts on average.

Charge Controller: I know very little about these. I just bought one and stuck it in. They are there to prevent overcharging (hah!), and I believe, prevent back flow of electricity once the sun drops.

A word about power inverters... I have heard (not confirmed it myself), that for every 4 watts of power being consumed, the inverter uses 1 watt to power itself. Something to ponder if you are getting up to the 1200+ watt inverters...

Check here if you have some time to kill... http://www.expeditionportal.com/forum/threads/60087-Solar-Power-FAQ
 
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Alright, thanks for the reply's. That was what I was looking for. I had thought about doing the extra battery thing or just upgrading the electrical system but I think that will have to wait a while. I more so just wanted a easy system for interim use right now.
 
You can attach the trickle charger directly to the battery. They are designed and built that way. But don't expect to get enough power from it. That's why it's called a trickle charger.

If you want a true solar package, you will need a battery, a solar panel, and a charge controller.

The battery: Most likely the battery you already have in your rig. A lot of off roaders who spend extended times off grid will have at least one more battery hooked into the system.

Solar Panel: Solar panels come in a HUGE assortment of sizes, configurations, and output. My only advice is buy mono-chrystaline panels not poly. Buy the largest output panel that you can afford and are willing to cart around with you. Like most things, the more power you expect from it, the larger it will be physically. I have 3 (older) 15 watt panels equalling 45 watts on my RV. With a wife, 2 kids, and 2 house (marine) batteries, it's barely half of what I need. Maybe a third. It's almost impossible to get TOO much power from a mobile set-up. And remember the numbers the manufacturers give you for their panels is under IDEAL conditions. Things like clouds, shade, indirect sunlight, even too much dust will reduce the efficiency of the panel. My 45 watt panels on a good day will be lucky to produce 30 watts on average.

Charge Controller: I know very little about these. I just bought one and stuck it in. They are there to prevent overcharging (hah!), and I believe, prevent back flow of electricity once the sun drops.

A word about power inverters... I have heard (not confirmed it myself), that for every 4 watts of power being consumed, the inverter uses 1 watt to power itself. Something to ponder if you are getting up to the 1200+ watt inverters...

Check here if you have some time to kill... http://www.expeditionportal.com/forum/threads/60087-Solar-Power-FAQ

Every thing said here is absolutely correct. One thing to remember,....Solar panels are not an efficient way to produce electricity. Remember the millions if not billions of dollars spent by the green energy crowd to develop solar panels and then the research is a largely abandoned. Too many panels, too many square feet of real estate and too many standby batteries are needed to make this a viable alternative.

Having said all this, I have a 15 watt unit connected directly to my XJ batteries (2 900+ AMP) without a charge controller. With only one battery I would need a controller to prevent over charging of the battery in the South Florida summer.

A 15 watt solar charger at 100% put out only 1.15 AMP. Assuming a 12 volt battery requires 13 volts to charge it properly is about 15 (watts) divided by 13 (the required voltage of the battery) gives 1.15 AMP which is hardly usable in the real world to power anything.

I have to echo the above suggestion,...get as much solar chargers as you can afford, a charge controller and as much backup/storage batteries as you can afford. They could be made to work for you if the initial investment is large enough.
 
Thanks techno1154, without getting things too complicated right now. Could I simply do this. Add a inverter to the cigarette lighter that would give me a plug or two and then add a trickle charger to just use so I'm not completely draining the battery? The trickle charger I wouldn't want to mount but just use it as needed. I know it may not be the prettiest of most effective but if I could have something that works decently for under $50 that would be a win for me right now. My biggest concern would just be my speaker and phone. Thanks
 
Thanks techno1154, without getting things too complicated right now. Could I simply do this. Add a inverter to the cigarette lighter that would give me a plug or two and then add a trickle charger to just use so I'm not completely draining the battery? The trickle charger I wouldn't want to mount but just use it as needed. I know it may not be the prettiest of most effective but if I could have something that works decently for under $50 that would be a win for me right now. My biggest concern would just be my speaker and phone. Thanks

When I am out working (cellular RF Engineer) I use an inverter to power my laptop and other test equipment. The second battery in my XJ is to have a starting battery when it is time to go home. Driving up to 100 miles one away from home or my hotel do not allow me to carry my solar panel. Also quite often an AC outlet in not available.

The answer is yes you can use an inverter. You could use a charger with enough output to reduce or prevent the battery from draining.
 
Alright, thanks again for the info!
 
Nearly everything I power is ran by 12V or 5V USB so I've basically eliminated the need to cart along a large power inverter. I've got a small 400 watt inverter that i use to air up my air mattress with a 110 powered air pump that's built into the mattress. Or to power other small items like the battery charger for my saw.

I built a solar generator but rarely bring the panel along for it. I've made a few small changes since this video (such as removal of the HAM radio) but this box will pretty much power everything I want for a multi day trip. If I go over a 5 days or so I'll bring the panel but even then it's not typically needed since I can hook i into the Jeep's rear power outlet and charge it when I'm driving to the next camp site.

I have kicked around the idea of temp mounting my 100 watt panel on the roof rails for longer trips but.....eh.

 
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Solar panels are the revolutionary "tools" of nowadays...People are fond of eco-energy.. it's a good thing although some disadvantages of solar panels exist. It's more important for people to save money not the environment. I was thinking about this these days because my energy bills are outrageous. My decision was to get a quote on http://usave.co.uk/ and find another energy and gas supplier to save money was the best decision. Although, my wife always tells me to be eco and save energy.
 
does anybody can tell e how much a solar battery costs?

You need solar panels, PV (charge regulator) and batteries depending on your needs. Add in an assortment of wires and wire connectors.

You did not say what you are trying to accomplish.
 
if a solar panel provided 1 amp as suggested, and I assume that can only happen near high noon on a clear day, near the equator, then you might be better off simply running your Jeep alternator to keep your cell phone battery topped off. A car alternator can put out a lot more power than 1 amp, and gasoline is cheap, and the alternator can run day or night, sunny or cloudy. plus with an alternator you dont have to find a place to store the panel both when in use and when traveling, our XJs are tight on space. let the jeep alternator keep your jeep battery charged, and use that to charge your cell phone battery.

you can also buy an external battery pack for some cell phones, thus giving days of use. then when you drive, charge that up with your jeep alternator. your jeep alternator can make plenty of excess power to charge an extra battery that can he dedicated to phone charging.

simplicity sometimes wins.
 
This is a 100w setup I added about three years ago. I think it was under $200 for the kit including panel, cables, charge controller AND the aluminum to attach it under the roof rails. It works great. I don't think at all about leaving the inverter on to charge phones/laptops. If I park in the sun, the fridge stays cold for days.
The charge controller feeds the dual-battery setup I had already installed. The HellRoaring controller charges the aux battery once the main battery is full. I think it is worth it.
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