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rocktot
07-31-2012, 15:40
Anyone have a good recommend for a (cheap) but functional solar setup with LED lights or something of that nature? (For travel trailer)

Omicron
08-01-2012, 00:13
I'd start with replacing the lights in the RV with LED versions thereof. Or even cheaper, you can certainly get LED bulb replacements for the 12V bulbs that are in there now. Once that's done, I'd look at solar panels that wire in and charge your 12V battery system. I know there are kits out there to do this, and having the battery in place and everything already designed to run 12V is more than 3/4 of the battle.

Hope this helps.

jerrymrc
08-01-2012, 19:55
You can take a look here at what I did. Do understand your inverter needs to be up to snuff to use them full time. http://www.falfiles.com/forums/showthread.php?t=255553

And solar panels. http://www.falfiles.com/forums/showthread.php?t=215773

We have gone over this here but this is the easy way since back then we did not have a S&P forum. I asked and look what it got me. :)

HoneyBadger
08-01-2012, 21:01
You can take a look here at what I did. Do understand your inverter needs to be up to snuff to use them full time. http://www.falfiles.com/forums/showthread.php?t=255553

And solar panels. http://www.falfiles.com/forums/showthread.php?t=215773

We have gone over this here but this is the easy way since back then we did not have a S&P forum. I asked and look what it got me. :)

Jerry, is this process any different than say, wiring a cabin for 12V and solar?

rocktot
08-01-2012, 21:43
Hey, thanks- looks like solar panels got cheaper since 2007!

jerrymrc
08-02-2012, 18:41
Jerry, is this process any different than say, wiring a cabin for 12V and solar?

The things I have done work with the 12V system. I do have two 12V systems in my trailer. One runs most of the normal built in stuff and has solar charging and the other runs the entertainment stuff.

I used to dry camp for 4-7 days at a time. My trailer does not know what hook-ups are. Power wise I can go forever but since we just camp the fridge runs on propane and we carry 50gal of water. After 7 days we always had 1/2 the water and 3/4 propane.

This was never a test to see how far we could go but many times it was just to get comfortable with the tools we had. I always took my sat system and the SW. I used to joke that I watched more TV camping than at home just because I could in the middle of nowhere. Second system has 200AH of AGM batteries and 100W of panels. main system has 300AH of wet cells and 100W of panels.

I have enough cells to build another 200W of panels and also have another 400+AH of AGM batteries on hand. Used AGM batteries are easy for me to come by at the moment since we have equipment that has to have them changed out every 36 months. All are around 30AH.[Flower]

I use them many places like my battery backup for the pellet stove that will run 6 hours after the power goes out.[Beer]

rocktot
08-02-2012, 21:23
So, can you compress, what would you need to run say up to 8 LED lights in a camper, 10 hours a day (max)? What would be the safe minimum batter size, controller, solar cell size??

rocktot
08-03-2012, 18:18
Ok, what about these solar deals? They look like they could power some LEDs for a long time, yet only 15-30 watt solar panel? Does this look like it will work, and can you show your math on this???

http://www.goalzero.com/shop/p/60/Escape-150-Adventure-Kit/1:2

jerrymrc
08-03-2012, 22:31
Ok, what about these solar deals? They look like they could power some LEDs for a long time, yet only 15-30 watt solar panel? Does this look like it will work, and can you show your math on this???

http://www.goalzero.com/shop/p/60/Escape-150-Adventure-Kit/1:2

It is late but some of the basics. 200 ah battery. 10 -5 Watt led's. 50W panel.

For the sake of simplicity the lights. We have 50 watts of lights. 50 divided by 12= 4.16 amps. 4.16 x 10 hours= 41.6 AH.

So for this we have taken 41.6 out of the battery.

So now we have the panel. 50 watt panel. Under the best conditions it puts out 4.16 amps @ 12V. we took 41.6 out of the battery so we need it to provide 10 hours of light to put it back (10X4.16) = 41.6

So lets get a 100W panel. 100W panel puts out 8.32A so doing the math 8.32A X 5 hours puts back 41.6 AH.

Always better to have too much storage and more panel. With a good controller one can never have enough PV's. Now I am in the camp that I would rather have 4-50W panels than one 200. Batteries as well.

And when it comes to actual power draw you need to be able to use a meter to check. My lights that used 6-.5W led's draw 5.2W and that is with the two resistors that do get warm so anything that gets warm is drawing power.[Flower]

Just some thoughts for now. I did go back and look at my old thread and much of the math has been done there as well.

In the end lighting the camper used 1/3 the power of regular bulbs.[Beer] I am a goofball. Let me look at it tomorrow to answer your real question but most that I have seen do not live up to the hype.[Shock] I looked.[Puke]Will explain later but if you do some math on that from the numbers I posted above......... The battery alone is the size in my UPS that keeps my puter alive for 15 min. [Bang]

offgrid
08-06-2012, 15:53
It is late but some of the basics. 200 ah battery. 10 -5 Watt led's. 50W panel.

For the sake of simplicity the lights. We have 50 watts of lights. 50 divided by 12= 4.16 amps. 4.16 x 10 hours= 41.6 AH.

So for this we have taken 41.6 out of the battery.

So now we have the panel. 50 watt panel. Under the best conditions it puts out 4.16 amps @ 12V. we took 41.6 out of the battery so we need it to provide 10 hours of light to put it back (10X4.16) = 41.6

So lets get a 100W panel. 100W panel puts out 8.32A so doing the math 8.32A X 5 hours puts back 41.6 AH.

Always better to have too much storage and more panel. With a good controller one can never have enough PV's. Now I am in the camp that I would rather have 4-50W panels than one 200. Batteries as well.

And when it comes to actual power draw you need to be able to use a meter to check. My lights that used 6-.5W led's draw 5.2W and that is with the two resistors that do get warm so anything that gets warm is drawing power.[Flower]

Just some thoughts for now. I did go back and look at my old thread and much of the math has been done there as well.

In the end lighting the camper used 1/3 the power of regular bulbs.[Beer] I am a goofball. Let me look at it tomorrow to answer your real question but most that I have seen do not live up to the hype.[Shock] I looked.[Puke]Will explain later but if you do some math on that from the numbers I posted above......... The battery alone is the size in my UPS that keeps my puter alive for 15 min. [Bang]


A few things to add to the above.

Battery capacity, 3-4 day battery (bank) not going below 50% state of charge is ideal.

Charging current, 1/20th (c/20) of battery capacity is ideal.

With the above example, 41.6 amp hrs used in 24hrs suggest a battery bank of 41.6 x 4 = 166.4 x 2 = 332 AH battery bank. For a c/20 charging current, 16.6 amps of charging source.

Max current output of a nominal 12 volt panel is usually based on 17 volts +/-. So for example a 100 watt panel/17 = 5.88 max current output. Would suggest 3-100 watt panels (17.64 amps) for the system example.

HoneyBadger, if you are wiring a cabin for 12V's, simply wire it as if it's 120VAC, small breaker panel.... Only difference use DC rated light switches. An maybe DC outlets, they have a different plug/lug pattern, so a 120VAC device can't accidentally plugged into them.

HoneyBadger
08-06-2012, 17:52
Thanks for the tip Offgrid. In your opinion, would it be easier to set up a cabin in 110VAC or 12VDC? The plan is to be 100% self-sufficient. Mostly solar and maybe some wind turbines depending on the area.

I would want enough power to run basic appliances like fridge and freezer, etc. Is that reasonable? I know fridge and freezer draw lots of current.

Thanks

offgrid
08-06-2012, 20:09
Thanks for the tip Offgrid. In your opinion, would it be easier to set up a cabin in 110VAC or 12VDC? The plan is to be 100% self-sufficient. Mostly solar and maybe some wind turbines depending on the area.

I would want enough power to run basic appliances like fridge and freezer, etc. Is that reasonable? I know fridge and freezer draw lots of current.

Thanks

If you are planning to run a fridge, freezer... set it up for 120/240vac.

Our offgrid home is wired 120/240vac.

100% self-sufficient would be tough, I'm married! Use about 300 gallons of propane a year for cooking, dryer, and radiant heat (boiler). Have solar hot water collectors for domestic hot water, works well, covers about 90% of our hot water needs. If I were to build again, would use solar hot water collectors for heating as well.

HoneyBadger
08-06-2012, 20:41
If you are planning to run a fridge, freezer... set it up for 120/240vac.

Our offgrid home is wired 120/240vac.

100% self-sufficient would be tough, I'm married! Use about 300 gallons of propane a year for cooking, dryer, and radiant heat (boiler). Have solar hot water collectors for domestic hot water, works well, covers about 90% of our hot water needs. If I were to build again, would use solar hot water collectors for heating as well.

How well do the solar water heaters work? My wife takes EXTREMELY hot showers... the water temp is too hot for me.. But she can't seem to shake this "necessity". Could you run your water line through a solar heater before running it through a standard hot water heater (like a 20gal tank) to save on gas?

offgrid
08-07-2012, 14:16
How well do the solar water heaters work? My wife takes EXTREMELY hot showers... the water temp is too hot for me.. But she can't seem to shake this "necessity". Could you run your water line through a solar heater before running it through a standard hot water heater (like a 20gal tank) to save on gas?

Weekend cabin or full-time?

HoneyBadger
08-07-2012, 15:50
Weekend cabin or full-time?

Weekend cabin, hunting trips, etc unless the SHTF. Then full time [Tooth]