diy solar

diy solar

Planning a grid-tie system

Excellent observations and advice. I will brace the EMT as suggested. I didn't even know about IMT. Home Depot lists it, but says it's unavailable. Is it rare or something? Western Tube in Long Beach has it, but I have a feeling they sell only to the trade. I'll ask though.
 
Generally EMT is used as conduit for many indoor applications. If improperly used underground it rusts through quickly. For your outdoor use it should be reasonably durable. The thin zinc "pre-galvanized" or "electro galvanized" protects against rust for a few years. Same for U-channel with such coating, I've read 5 years. Heavy coating of hot-dip galvanized is supposed to last 20 years. That's not available on EMT.

Rigid or IMT is thick, uses threaded fittings. When I was looking for 1" rigid, my local Home Depot didn't stock it but then I realized they had IMT so used that.



Custom threading conduit takes the right tools, which can be expensive but I have them. Harbor Freight has a cheapie set, much less than "Rigid" brand. I also have a motorized power head which make work faster and is about the only way I can do 2" sizes.

Making ground mounts for panels required several fittings ("T" and adjustable angles) that would bolt on instead of threading. I bought most of those from unirac, but I also saw a variety pipe hardware like you're using. I made a few things cutting/drilling, and welding in the case if steel.
 
That is helpful information. I wouldn't have thought of using EMT underground, for very good reasons it turns out! My system will be seasonal, but still, it'll be in a little weather, though, not much! Portability is important. Oh, and Home Depot doesn't sell IMT anywhere near me. Bah!
 
That is helpful information. I wouldn't have thought of using EMT underground, for very good reasons it turns out! My system will be seasonal, but still, it'll be in a little weather, though, not much! Portability is important. Oh, and Home Depot doesn't sell IMT anywhere near me. Bah!
Rigid conduit then? Steel water or gas pipe, for sure. Maybe some sizes but not others.
Lowes, ACE, many vendors.

Steel gets heavy when thick wall material is used. There is even aluminum conduit, but harder to come by.

EMT should be fine for a small array so long as you design triangles, loaded only at the corners so tubes see only tension/compression.
It's straight runs with distributed load (several PV panels) where avoiding torsional load is difficult.
 
Good. It will be thinwall with triangles. And I will consider having each panel supported by it's own, independent structure. Thanks for the help!
 
Here are a couple of panels on an easel that was available. They power some DC fans.
Tethered to stakes so it doesn't blow over and break the gas meter. Again.

panels easle.jpg

You might be able to make swing-out legs, possibly two panels hinged to fold together, wheels to move easily. Sandbags to secure?

Or, hooks to hang off the eaves, struts to the wall. Couple different points on the wall and you have seasonal tilt.
 
Yes. The easel is actually mason's scaffolding, if I'm not mistaken. I have two of them, maybe four. With this set up, you would change the angle by a simple adjusting of the lines. Brilliant! Oh, I like this. So, at my cabin, I could take full advantage of the sun, by placing them in just such an apparatus as this on the ground. I'll first see how rooftop mounting works out, but then try this and compare the results. My cabin is in Canada, so I'll need every watt I can get. Very excellent! Thank you.

Your note, "break the gas meter. Again," sounds bad! Was it? And yes, it needs to be super anchored to the ground!
 
Your note, "break the gas meter. Again," sounds bad! Was it? And yes, it needs to be super anchored to the ground!

The gas kept flowing. The dials stopped turning. :)

When I finally realized what was going on with the bills (not just zero due to credits they sometimes issue) I notified PG&E, expecting it to be fixed in the summer. But they responded something like they couldn't verify I was the customer at the specified site.
They replaced it some months later. But wouldn't turn it on until they and I were present at the same time. They've got some hidden control, so I couldn't just turn on the main valve and light my pilots.
Previous 3 months bill was corrected, estimating by the next months bill. Which was very low, of course. Even though it was the middle of winter. :)
 
Well now, that's not bad at all. Last summer, or rather, the summer before, I felled a seventy foot tree at my cabin property. It was very close to the power lines. I got the cut right, it just wouldn't fall. So, I pushed it and it fell back toward the power lines. It stopped on the closed cut. Turns out that a tree grows a lot more weight on its south side. So, I hooked up a come-a-long and pulled it over. It was the biggest tree I ever felled! Eighty years old and heavy. Scared the daylights out of my wife and kid, and me! Oh the mess it would have gotten me into if it took out the power! Lesson learned.
 
As I have been planning my system I found ten 240 watt panels for $38 each, instead of the new ones for $110. I'll get 'em, but the thought suddenly occurred to me, since I am a newbie, do solar panels need to be rule 24 compliant? I figure the answer is no. Solar panels that have several years use are OK in regard to regulations, right?
 
For grid-tie and inspected system, PV panels should have UL labels. Some panels on the market had labels stripped.

What do you mean by "rule 24 compliant"?

Title 24 is energy efficiency.
Rule 21 is a California rule for inverters to help prevent grid instability.

I read from a forum member in Australia that perfectly good PV panels are required to be replaced when an inverter is replaced, but nothing like that in the U.S. Used panels should be fine.
 
As I have been planning my system I found ten 240 watt panels for $38 each, instead of the new ones for $110.

Check here for comparison:


One of his listings is $0.36/W with manufacturer's warranty


Yes, that's over twice the price you're looking at. But you were only going to pay $380 for PV panels; balance of system may be much more, so cheapest panels is diminishing returns. I would want to over-panel, get more Wh from the system if possible.
 
Excellent and thanks for your quick advice. These panels are sort of starter panels, enough to get my feet wet. My wife likes the idea of starting at a low price and moving up as my competence increases. With all that I am doing, I know that I won't have a grid tie system in place for years. I will have off grid systems in months on the side of my house and when I am allowed to go to my place in Canada - a remote cabin which sits idle for months and is exposed to theft (and expensive solar panels are quite attractive up there)! So, I'll go with these and look toward the mono solar panels for my planned grid tie system. My wife is on board with this plan. And that's worth a lot. Plus, I had no idea that mono solar panels were so affordable. This is a good time to go solar!
 
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