Treehouse power

Hello all! I am planning to power my kid's treehouse with all 12v stuff. Actually I already am with an extension chord and an ac/dc 30 amp power supply. I currently have a 50w GMRS radio and an old car stereo with a couple of 6 1/2" speakers. Planning to add some led lighting and maybe a small fan. I have read some of the build guides and have an idea of what I'll need. Planning a 20 amp MPPT controller and 100 Ah AGM battery unless the SOK ones come back in stock.

The big question I have is, there is nowhere good to mount panels on the treehouse, but I have a shed with a southerly facing roof about 50'-60' away. Would it be practical to mount the panel(s) there and run lines to the treehouse where the controller and battery would be stored? Any other suggestions in general would be appreciated. Thanks!

I will also add it would be sweet to power some led lighting in said shed but I'm guessing that might be best having a separate system with co-located panels?

"my kid's treehouse"

You can be straight with us. It's your treehouse.


I'd keep the controller and battery in the shed and run a line from the shed to the treehouse and see how it goes.

There's a table around here that will explain the voltage drop you can expect for the line based on gauge and distance.

When you start to plan that wire run, higher voltages, which will probably require an MPPT controller will do amazing things to minimize voltage loss. THis is my favorite calculator:


After doing some calculations and looked at connectors and amperage, saw that sticking to 10 AWG made the build much easier.

Before I knew about voltage loss, I simply spliced a 25 foot wire into a solar panel. There was so much voltage loss, the panel did not generate enough charge to trickle charge a battery. That was probably a 18 volt, 5 watt panel.

Thanks for the input gents! And yes, guilty as charged. I built the treehouse (or house in a tree as my wife calls it) for the kids but I'm living out all my childhood visions of grandeur through it lol.

I am familiar with voltage drop especially for 12v but after looking at that calculator, my feelings got hurt by just how much their would be. Clearly higher voltage is required. I guess that's why i was thinking about panels on the shed and the controller and battery in the treehouse--I thought maybe I could wire the panels in series and up the voltage to the controller? Should I consider an inverter and running 120v from the shed to the treehouse, then converting it back?

I love the idea of the controller and batteries living in the shed for several reasons, not least of which is it would make shed lighting easy, but power to the treehouse is ironically the priority. Safety and weight are other reasons. I'm attaching a not great photo of said treehouse and you can see the shed in the background. Treehouse roof faces E/W and will be shaded in the summer. Shed roof faces S/N and has an unobstructed view of the sky.

SkylinesSuck said:

I am familiar with voltage drop especially for 12v but after looking at that calculator, my feelings got hurt by just how much their would be. Clearly higher voltage is required. I guess that's why i was thinking about panels on the shed and the controller and battery in the treehouse--I thought maybe I could wire the panels in series and up the voltage to the controller? Should I consider an inverter and running 120v from the shed to the treehouse, then converting it back?

I love the idea of the controller and batteries living in the shed for several reasons, not least of which is it would make shed lighting easy, but power to the treehouse is ironically the priority. Safety and weight are other reasons. I'm attaching a not great photo of said treehouse and you can see the shed in the background. Treehouse roof faces E/W and will be shaded in the summer. Shed roof faces S/N and has an unobstructed view of the sky.

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If you gave us a hint of what panels you were using the voltage drop mystery could be solved.
Did you have the panels?
Specs?

No panels. I'll buy what you guys tell me

SkylinesSuck said:

No panels. I'll buy what you guys tell me

Click to expand...

Buying cheap panels locally saves on shipping so where is you at?
20A SCC at 12V is good for 240 watts of panels.

I'm in northern VA not far outside DC. And according to the power supply I currently have getting 12v from the extension cord, it says I'm currently using 10-15amps with both the stereo playing music and the GMRS radio transmitting which it does rarely. I'd like plenty of overhead though.

What is SCC?

Ahh, just figured it out. Solar charge controller. Maybe 40 amp and more panels is better?

SkylinesSuck said:

I'm in northern VA not far outside DC. And according to the power supply I currently have getting 12v from the extension cord, it says I'm currently using 10-15amps with both the stereo playing music and the GMRS radio transmitting which it does rarely. I'd like plenty of overhead though.

What is SCC?

Click to expand...

First do a power audit to figure out how many watt hours a day.
The beer fridge will be the biggest consumer.

Then see how many sun hours you get a day.


60 feet is no problem for voltage drop with a couple of panels in series for higher voltage and low amps.

How do I do a power audit?

Okay, I realized I have a smart plug that measures power on the extension cord now. It has other things on it like patio lights and a small space heater at the moment that I won't expect the solar setup to run. That being said, it looks like I fluctuate from .01 (most days) to 5KW.h (occasionally when we run the heater and have the patio lights on which again, I don't plan to put on solar unless I could?).

I also measured and it is exactly 60' from shed to treehouse. Add another 20' for routing up and into the structures and call it an 80' run I need. I do not mind filling up the roof of that shed with panels.

SkylinesSuck said:

Thanks for the input gents! And yes, guilty as charged. I built the treehouse (or house in a tree as my wife calls it) for the kids but I'm living out all my childhood visions of grandeur through it lol.

I am familiar with voltage drop especially for 12v but after looking at that calculator, my feelings got hurt by just how much their would be. Clearly higher voltage is required. I guess that's why i was thinking about panels on the shed and the controller and battery in the treehouse--I thought maybe I could wire the panels in series and up the voltage to the controller? Should I consider an inverter and running 120v from the shed to the treehouse, then converting it back?

I love the idea of the controller and batteries living in the shed for several reasons, not least of which is it would make shed lighting easy, but power to the treehouse is ironically the priority. Safety and weight are other reasons. I'm attaching a not great photo of said treehouse and you can see the shed in the background. Treehouse roof faces E/W and will be shaded in the summer. Shed roof faces S/N and has an unobstructed view of the sky.

Click to expand...

I found my new home! Complete with rock wall.

Why not have everything in the shed and just run a 120 volt line to the tree house? What are we looking at running in the tree house and shed - just a couple of basic lights, maybe a small tv and DVD player; central air, future power needs?

Based on what you listed that doesn't seem to be much. You can get a 5 watt LED USB light with switch that provides a lot of light with little power. You will want a battery monitor - with AGM you don't want to go below 50%. I just picked up a Harbor Freight 4' LED light $29.99 (??) on sale and that uses 56 watts

Thanks! Come on over, I won't charge much for rent ?

I am not at all against running 120 to the treehouse from the shed. One thing to keep in mind though is I'll need to convert it back to 12v again for at least the car stereo and GMRS radio. I'd like to do the led lighting in 12v also because the kids picked out some crazy color changing ones for the second floor/loft area. I'm actually having fun digging out old car electronics and installing it up there with them, plus I can use some of the junk I have sitting around. Taught my 8 yr old how to solder when we were wiring up the stereo ? I don't think those use much power (especially just on standby/RX). I could see adding a small TV/DVD and fan in the future if power allowed. If I could have enough to run the patio lights and space heater, that would be a great bonus and I'd be willing to drop a little more coin on that but I realize those are big power eaters though. I don't mind occasionally dragging an extension cord out there for the rare times we "camp" up there in the winter.

We will probably only live here another 4-5 years so long term battery life isn't crucial to me, but I'm interested in LiFEPO4 if the cost is right.

SkylinesSuck said:

I also measured and it is exactly 60' from shed to treehouse. Add another 20' for routing up and into the structures and call it an 80' run I need. I do not mind filling up the roof of that shed with panels.

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As I look at the shed, looks like the shed could get quite a bit of shade.

I have four 100 watt panels that are putting out 6 amps each in full sun. These panels are about 48" X 21". When I walk past the panel and only my head is blocking the sun, output drops to 1 amp.

If shade is the case, some thought needs to go into placing the panels and production could be much lower than what a program like PV watts gives you.

It does catch shadows in the morning and evening, yes. From maybe 1000-1600 it's getting unshaded sun though. Give or take. Are you saying some shade should make me look more at wiring the panels in parellel?

Forbisher said:

Buying cheap panels locally saves on shipping so where is you at?
20A SCC at 12V is good for 240 watts of panels.

Click to expand...

Any tips on places to look for local panels and maybe batteries as well?

SkylinesSuck said:

It does catch shadows in the morning and evening, yes. From maybe 1000-1600 it's getting unshaded sun though. Give or take. Are you saying some shade should make me look more at wiring the panels in parellel?

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I think as many in parallel as practical is good.

I wanted all parallel with my RV build and my six - 100 watt roof panels. Because of voltage loss, I had to do 3S2P.

I have never tested the results of shade in my 3S2P roof panels like I did with my four - 100 watt portable ground panels in parallel on the ground. Someday I'll climb up on the ladder and see how output is effected.

SkylinesSuck said:

Any tips on places to look for local panels and maybe batteries as well?

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Craigslist
OfferUp
Local solar companies.
Local eBay sales.
I would not buy used lead acid batteries but you might find a almost new LFP battery.