How do you house your setup? Help needed on a shed

cptdondo

I'm looking for ideas on a shed for my solar setup - 8 panels, 8 6-v batteries, inverter, MPPT controller.  

This is in the high desert in New Mexico, and it get HOT HOT HOT.  I will not be there during the hottest part of the year, so how do I house the equipment and keep it from baking into slag when the outside temps hit 100*++?  How do I keep the batteries from cooking and drying out?

The shed needs to be secure and solid.  The simplest is a 20' container, but I think that would be too hot during the summer.

706jim

Start by locating the shed in a shady area. Another idea might be to put the batteries below ground where the temperature is cooler and less variable. And possibly small fans to help with ventilation.

cptdondo

706jim said:

Start by locating the shed in a shady area. Another idea might be to put the batteries below ground where the temperature is cooler and less variable. And possibly small fans to help with ventilation.

The nearest shade is about 8 miles away.   But I like the idea of housing them below ground. I can excavate a hole cheap, and there's no rain to speak of.    

What about using concrete block for the walls?  Would that help?

706jim

Years ago the only refrigeration was a hole in the ground. Might be the way to go if there's no shade close by.

Photowhit

My power center and battery were going to live outside, so I put up a big wall of solar panels to shade them!

I would bury them or build a berm shelter. Use concrete blocks to build a smallish block room then push dirt/sand up and around it. It's a challenge, electronics don't like heat either!

Wheelman55

Two things. 

Concrete block transfers heat. Suggest you use a better insulator. Below ground is a good idea. 

Use LiFeP04 batteries and simply shut the system down when you aren’t there

mike95490

Use the panels to generate shade over the shed roof.   use tall standoffs to reduce heat buildup between panels & roof

Use timers and fans to pre-chill   the shed   interior at night, and leave the eve's blocking out, so that the top of the wall, is just a screened slot the entire length, lets hot air out, without letting cool air spill out .

mcgivor

Being a desert you might want to consider underground like they do in Australia 
https://youtu.be/-1XSKu3pK8A

littleharbor2

cptdondo said:

The nearest shade is about 8 miles away.   But I like the idea of housing them below ground. I can excavate a hole cheap, and there's no rain to speak of.    

How about making shade?  A basic Ramada could be built over the container. Make it with large enough overhangs to shade the sides and mount your panels on it.Too much work?

Wheelman55

Make sure to use a white roof with plenty of air circulation. Any other color roof will be at least 30 F degrees hotter. Same for the walls of a small shed if you can handle the Mediterranean look. 

Experiment with an IR heat gun. You will be astounded by the heat difference between white and any other color. 

I’ve personally had good results using “attic foil” beneath a white tin roof. Hang the foil so that it has a 1-1/2” or bigger belly under the tin. 

The foil reflects most of the radiant heat back through the tin roof. I got mine from a Texas mfg. Do not use the “insulated foil” as it breaks down. All you need is the radiant barrier. 

Best of luck. 

softdown

There is solar paint that keeps the sun from heating a structure significantly over ambient temperatures. It is about like aluminum in terms of heat absorption. Works well but takes a couple coats - there is no dark dye in it.

You said you can excavate - there you go. Should be cool enough when 6' deep or so. Avoiding heat is paramount.

Lot to be said for building partially underground. Nuke proof for one thing. Close to Los Alamos? Some big military complex down there seems to use a great deal of light - shows up in night pictures. Sandia Labs? The name escapes me at the moment.

mike95490

I put generator shed and inverter shed back to back, the high side of the roof is open screen for ventilation, generator shed has chainlink gate as a door for ventilation.

cptdondo

softdown Close to Los Alamos? Some big military complex down there seems to use a great deal of light - shows up in night pictures. Sandia Labs? The name escapes me at the moment. 

Close enough that my satellite and cell phone wig out at random times.

Just heard from the power company. Looks like I could have power for about $15k - which makes it very attractive compared to solar/wind.

softdown

Given the heat producing shortened lives of batteries and electronics - I'd go with grid power. I spent 20k on solar doing the work myself. One still has to be extremely vigilant about managing ones own power plant - so to speak. Your grid power should be a reasonable price I would think.

Dave Angelini

The OP should also just consider the batteries as expendable. They may only last 5 years and it is just the cost of doing a power system in a place that is not friendly.

If you can do power for 15K you would be pretty crazy not to solve this the easy way.

The best way I have found to do this challenge is build a ground floor garage and living upstairs. I think it is called a coachmen design to architects. A bit harder to cool the upstairs but guaranteed cool down stairs. Probably less than 78 down there and 105 outside. A split heat pump upstairs when you are there and you are in the catbird seat. Probably done this over 50 times now.

BB.

Check your minimum monthly billing... A few folks (in Canada?) had a weekend cabin, and a small solar power system + genset was a better deal that paying 12 months a year minimum bill (something like $48 to $96 a month or so at the time???).

-Bill