Solar power Trailer

[suburbancowboy]

Several months ago there was a thread talking about solar power trailer.  It peaked my curiosity and so I started to research the possibility.  After some research I decided to build one.  I had a 800 dollar budget and started it in the late winter.  After a few starts and stops I completed my trailer a few weeks ago and got it hauled up to the cabin.  It works great and supplies all the power we need.  I run an extension cord from the trailer to the cabin.  I have a power strip in the cabin for everything that I need power for.  It works way better than my generator.  Here are a few images.

Frame


Platform




Panels


Internals

[firefox]

Looks good! Nice picture show and tell.
Bruce

[bayview]

  Fantastic!    

  Would you please take the time and post a wiring schematic.   With the various components you used . . .

  I am wanting to build a small self contained travel trailer with solar.   This might be just the "ticket".

  Thanks

/

[diyfrank]

Looks good. Can you break down your cost for the parts for us? 

[suburbancowboy]

Here is the cost breakdown.


Trailer                                150   \
3 solar panel kits @ 160           480   Harbor Freight
1500 watt inverter               100   /

3 batteries @ 55              165   Walmart

Lumber                               80   \
Hardware                            40   Home Depot
Paint                                  25   /
                    -----
Total                    1040

Habor Freight has been running 159 coupons for their solar panel kits for the last several months.  Get a coupon or it will cost you 249 regular price. 
The  trailer is on sale once a month for 150.  Get the one with the 12 inch wheels.  It will travel much easier with less bounce.  It is also the smaller
one, not the 4X8 one.

As far as wiring goes, the three batteries are wired in parallel.  The output stays at 12 volts but the amps are tripled.  I used a 12volt inverter.  It is very easy to hook up.  Pos to pos and neg to neg.  If you have access to a different inverter I would get it.  The cost for the habor freight one very good but it is very noisy.

I keep an extension cord and pair of jumper cables in the trailer just in case.

[Erin]

This is genius!   

[Tickhill]

I found this website a couple of weeks ago and my pioneer spirit has been refreshed! Great looking trailer setup, how do you store the panels for "transit". I got into solar panels last year at my father's shop. We did it as a learning hobby. My father was a hydro operator with TVA and COE, so he was all for the power generation aspect of solar and also wind. What are you powering with your setup?
thanks,

[325ABN]

How do you protect the panels when you are pulling the trailer down the road?

[suburbancowboy]

The panels are easy to slide in and out.  So when I travel I just unhook them from the charge controller, slide them out and put them in the back seat in the truck.  When I started the project I was going to build racks in the trailer to store them in, but decided to save the time and just put them in the truck.  I will probably still put in the rack inside but it will just be fore winter storage.

[Dave Sparks]

http://picasaweb.google.com/campososolar/MyPictures#5491951313601718626

Here is a nice one that OSU did. Nine Sanyo 215 watt panels on a wattsun tracker. The array goes horizontal for the road.


I thought I fixed it, dang not that good yet....

ED: fixed the link for ya' Dave    - MD

[suburbancowboy]

For those of you who are interested in duplicating this trailer harbor frieght in their sunday ad today has the 45 watt solar panel kit on sale for 139 with a coupon.  This is the lowest price I have ever seen.   

[Pritch]

Good for you!  I think this is the least expensive solar trailer I have seen to date!  These trailers make a lot of sense for seasonal cabins.     

I'm curious why you built the cargo box as big as you did.  Is the space necessary for venting the equipment or was that to accomodate panel storage?  Also, wouldn't a single high output panel cost less and take up less room?  (There is probably a good reason why this wouldn't work, but I'm pretty clueless about this stuff!) 

[MikeOnBike]

For those of you who are interested in duplicating this trailer harbor frieght in their sunday ad today has the 45 watt solar panel kit on sale for 139 with a coupon.  This is the lowest price I have ever seen.   

Thanks for the tip.  I mentioned this to my wife and she dug the coupon out of the recycling bin and said 'Happy Birthday'.  We are building a 'shed' on our mtn property this summer and this should be perfect for lights, music, etc.  The local Harbor Freight has 6 in stock.

I was looking at the online manual and I'm a little concerned with this statement:

Note: It is normal to see up to 20% degradation in amorphous silicon solar panel performance within the first 6 months before the amorphous coating stabilizes.

So I should expect to loose 9 watts of output? 

I still think it is a great price for a ~35-45 watt panel(s).  The price per watt for the smaller systems is often $5/watt or greater.

Very nice project.  Thanks for sharing!

[suburbancowboy]

The size of the box was sized to holding the panels that are hanging on the side.  If it had been shorter the side panel brackets would have been hitting the wheel well covers.

[MikeOnBike]

surburbancowboy,

Thank you very much for the coupon tip.  I picked up the solar kit last night and in the fading light hooked everything up and it all checked out.

Next week we are headed camping at a no utilities campground,  it will be very interesting to see how much the kit extends my run-time on the trailer batteries.  After that the kit will spend the rest of the year at our mtn. property supplying power for our 10x12 storage/sleeping shed.

http://countryplans.com/smf/index.php?topic=9024.msg118092#msg118092

[Solar Burrito]

I was looking at the online manual and I'm a little concerned with this statement:

Note: It is normal to see up to 20% degradation in amorphous silicon solar panel performance within the first 6 months before the amorphous coating stabilizes.

So I should expect to loose 9 watts of output? 

I still think it is a great price for a ~35-45 watt panel(s).  The price per watt for the smaller systems is often $5/watt or greater.

That's a great idea you have with the solar trailer, I love harbor freight for 1 time use tools but beware of Anamorphous Solar panels (black ones).

You get what you pay for. Amorphous solar panels give solar power a bad reputation in general. Harbor Freight selling them for that price is a major clue. While that's a great price you get what you pay for and highly doubt their package will produce anything close to 45 watts. They will only last 5 years max. The more expensive and much better Poly Crystalline and Mono Crystalline (blueish panels) will last for 30 years and give you the rated power longer into the solar day. Some built by Siemens in the 70's are still going. Don't hesitate to buy these used.

Experiment with your setup and look for some larger Mono Crystalline panels used in the mean time, you'll get far more power out for a much longer period of time. The rest of your system is totally interchangable which is cool. Also I'd beware of Harbor Freight's charge controller with the voltage readout, not sure why it's so big but test it to see if it's a power hog. Cheap Chinese electronics aren't known for efficiency. I'd buy one charge controller to feed all your panels into your battery. Fuse each panel.

That said this is a great idea and very cool so don't take any of these ramblings as criticism just to manage your expectations. Depending on your power needs this might fill them for many years. I can see a radio/speakers lights all kinds of things mounted to this trailer.

[suburbancowboy]

Currently I connect an extension cord to the inverter that goes into the bunkhouse.  I then plug a power strip into the cord.  What I run off it is a floor lamp with florescent light bulbs, a laptop, small surround sound system that plugs into the laptop, and a small 20" flat screen tv.  All the comforts of home.  I have a solar powered radio that sits in the window.  When I build the big cabin next spring I might upgrade the solar trailer with better panels.  I had to start somewhere and this is where I started.

[Solar Burrito]

It's an awesome start no doubt. Very creative, didn't meant to be critical just warning others to let their experience with amorphous panels taint their opinion on solar power. How long can you run this setup with the power use you describe?

If my place gets robbed like my neighbors did I may be doing a similar trailer or bunker.

[suburbancowboy]

I'm not sure how long this would run for.  I have had it up there the last three weekend and haven't run out yet.  Every other weekend I leave the charge contollers on all week.  The rest of the time they are only on while I am up there.  I guess I need to get some meters on it to find out what its capacity is.

[MikeOnBike]

Just got back from our camping trip.  I used the solar kit everyday and didn't have to borrow a genset from my camping buddies.  We didn't have a real heavy load on my camper batteries, just lights and water pump, no furnace, but generally we have to recharge them late into the week.  I was able to top them off every day with the solar kit.

The first day I hooked them up they were charging at 12.6v and 3.3 amps = 41.58 watts.  The meter on the charger matched my VOM.  I do think a three stage charge controller will be my next purchase so I can leave this unattended at our mountain site and not worry about overcharging.

Thanks again for the tip!

[suburbancowboy]

Just a quick update on usage.  This last weekend I was up at the lot doing some trim work on the bunk house.  During the evening I ran a floor lamp, laptop and sound system to watch a movie.  The next day I ran the air compressor for 4 house straight.  The whole setup handled it with no problems.  I love this thing.

[diyfrank]

I'm not sure how long this would run for.  I have had it up there the last three weekend and haven't run out yet.  Every other weekend I leave the charge contollers on all week.  The rest of the time they are only on while I am up there.  I guess I need to get some meters on it to find out what its capacity is.

I bought a 45 watt kit after reading this thread. I was wanting to have a small set up for lights.
I left the charge controller off when I left my cabin this week end but after rereading the manual it states,in the on position the regulator has over discharge protection, over charge protection and overload protection but will charge faster in the off position. charging in the off potion shuts off the 3 protections mention. The only way to stop from charging the battery's is to disconnect the panel at the controller.  Now I'm wondering if my battery is going to boil dry over the next couple weeks.