Main Solar system upgrade

Alternative energy sources
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The usual. As I have two large solar PV systems here, and my lab assistant just put one in, and others are interested in things like this, here's where that stuff goes. This is mostly for things that work now, not "gee someday a fusor will do this" -- we know that, but it's not someday yet.
The hope is to save anyone embarking on this sort of thing a lot of wasted time and money, as at least I have been off the grid since 1980 and have had a lot of practice (and made mistakes you won't have to).

Main Solar system upgrade

Postby Doug Coulter » Mon Feb 13, 2012 11:33 am

I'm making some major improvements on what was already a pretty nice system. There'll be a lot more to come on this thread, but I've just bought another 2.5kw worth of panels that have to be mounted along with the other 2kw I've gotten recently that aren't mounted yet - but which work fairly well just leaned on the wall. This time, I've added some real charge controllers to replace the frankenstein knife switch I've been using manually, and another inverter, this one a new Schneider XW-4024. I'll have to add at least one more charge controller to what is shown here to actually get all the panels under control and logged, but you know how building a big system sometimes goes - you do some of it on the fly.

Here's some of the new electronics. I probably already had plenty of inverters, but this one integrates in the new data aq system and puts out 240v unlike the others. I had one SQ wave inverter (3524) driving my air compressor and used as a charger off a generator, and the main SW-4024 which will continue to run "everything else" for now. The new one is going to run my Volt charger (for quicker charges), the welders, the lathe, and the fusor, all of which like 240v - I was using a fairly cheezy autotransformer before on those, and it kind of stinks as a solution. Having a bunch of inverters is nice, actually, as they regulate better when one gets a huge load spike. The various electronics here, including a web gateway, all talk, and have a lot of nifty features indeed, like programmable logic outputs to control other stuff, the ability to grow almost without limit (though I think I'm probably near the limit of what I'll ever want, much less need, now) and just plain efficiency. These solar controllers can harvest about 30% more energy from the panels than a straight hookup to the batteries, by using a fancy switcher to "impedance match" the panel output at it's max power output voltage to whatever the batteries happen to be at the moment, for example - most "24V" panels for example might make peak power at something like 35v or more, while the batteries might be run down to 23V - there's a lot of extra energy to be had there by using a buck conveter that regulates its input voltage down the the panel array max power (panels act kind of like a constant current source up to a voltage that is determined by the temperature of the panels - they act like forward biased diodes when open circuited).

So, while wiring is almost as much fun as plumbing (not!), I'm enjoying doing this. Now I can run more nasty loads with less noise to the delicate ones, and charge my car faster too! It was already better than power company power in those regards, but there was a little more possible, so I'm going for it!
SolarElectronicsUpgrade.jpg
New stuff. Don't drop that inverter on your foot as I did. If not for a lucky chunk of 2x4 taking some of that hit, I'd be in the hospital now.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Main Solar system upgrade

Postby Doug Coulter » Tue Mar 06, 2012 6:54 pm

I've added another solar controller to the stuff on the board in the pic above, and now for the real important stuff:
SolarAdd.jpg
New panels - now to put them into the sky


This reminds me of a story of some good ol boys around here who needed work and applied at a chicken farm. They were loggers by trade, but there was no work doing that, but they figured they could do almost anything (largely true). So they show up at the farm, and say we want work, what's the job. They get taken into this many acre warehouse utterly full of chickens - pretty much all touching. The guy points at the chickens and says - put these in those trucks over there, and you can go home with a paycheck. Needless to say, they were real happy to quit at the end of the day!

Same here - take that solar garden and put it in the sky. Easily said. This will pretty much cover the whole roof - the plan is to have top racks going back past the peak, and front racks going down over the steep part of the roof, but levered out some, and hopefully, all strong enough to handle the odd hurricane that comes through, while no one gets hurt doing this. I'm sure there will be some amusing video to come of this.

All those panels are already lashed up electrically - why not? And today, I got a new first. I finshed up a charge on the car, then went out to vote in the primaries and pay the phone bill, in one town. I came back, plugged the car back in, and by 3:00 - it was fully charged and ready to go again, the house batteries haven gotten full while I was out. So, two charges a day on the Volt! And it's not even deep summer yet!

I am hoping that shading the roof better will also make my puny AC work better in the summer...we'll see, but I've been a few decades without indoor AC, and it would be nice to have again.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Main Solar system upgrade

Postby Doug Coulter » Wed Mar 07, 2012 1:23 pm

Here's a vid of some of the other stuff in action, cycling while charging the Volt in the driveway. This is gonna work out real fine!
http://youtu.be/mAmdiBoB_Es

Boring but educational. This will only get better (a lot if past experience is any guide) when I get those guys up in the sky, instead of down in the shade and pointed north...).

Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Main Solar system upgrade

Postby Jerry » Sun Mar 11, 2012 4:41 pm

Pretty neat. Are the inverters you are using true sine or modified square. I am trying to figure out what kind I want to get to run my telescope in the field with the computer and fancy camera. They both have to run off AC but everything else I can get to run on 12v through DC/DC converters. I got a 12v @ 100AH lithium iron phosphate pack from a friend.
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Re: Main Solar system upgrade

Postby Doug Coulter » Mon Mar 12, 2012 8:35 am

They're pretty close to pure sine. One of them is just a big power D/A converter with three "trits" - each "bit" has 3 levels, and its own transformer with the trasnsformer outputs seriesed up . The newest one appears to be pure PWM drive into a single transformer, instead. You can see little glitches on the waveform with a scope, but they're pretty good - things don't hum and buzz.

For motors, it seems that modified sq wave works best, actually, at least in terms of torque and how fast they spin up. That might be good, as at low powers, the mod sq is about the only kind I see out there - you have to get into the big stuff to get sines. For a fixed, small, load, you might design a bandpass or low pass filter off one of those to get to sines if you needed them. That becomes almost impossible to do with varying loads and still getting any kind of voltage regulation, though. I'm using a sq wave inverter to run a couple of the larger motors around here, it makes them start harder - nice for the big air compressor.

The big Xantrex inverters can be used in 3's for 3 phase, fwiw.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Main Solar system upgrade

Postby Doug Coulter » Wed Apr 04, 2012 9:16 pm

Just some pix of the work in progress. I decided (hopefully not-stupid) to make wood racks for all the panels. Nice and heavy (we get wind), treated wood, and a heck of a lot less expensive than aluminum ones, which these days are getting pretty flimsy to hold prices down. I can predict it's not going to be too much fun hoisting these up there with a winch, and going to the steep dropoffs to put in the roof bolts, but sigh, you gotta do it. Hopefully only the once.
PanelRack.jpg
Rack in process. I got stainless steel studs with lag threads on one end, 1/4-20 on the other to mount the panels with.

SolarGarden.jpg
One set on its half-rack. It will take two sets to complete one "bay" on the roof, one over the peak, the other down in front.

VoltStation.jpg
Where the energy goes. At least some of it.


More pretty soon, I hope. Getting this done means not much else is, but then, having it done will let me do a lot more than I was before. Already, my gasoline consumption from backup generators went to near-zero, along with that for automobiles. That feels really good.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Main Solar system upgrade

Postby Doug Coulter » Thu Apr 26, 2012 10:21 am

We're now getting serious. We dropped one of the existing racks without incident, using a 4 strand rope hoist to control the descent. Then we tried to use the same setup to raise one of the new racks. This failed, we think due to the intense friction between the rope strands and the roof, despite us having put up some flashing for the ropes to slide over. But here's what it looks like now.
http://www.youtube.com/watch?v=3wkAmDaw ... e=youtu.be
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Main Solar system upgrade

Postby Doug Coulter » Mon Apr 30, 2012 5:05 pm

Now we're really getting serious. Rented this cool electric/hydraulic lift for about $670/week at Sunbelt rentals and towed it in. What a neat toy! It's not in just the right spot, but as you can see, it was pretty amazing to get the truck through there at all, and once we've mounted a few of the new racks up on the roof, we'll be able to position it better. More to come, of course.
http://www.youtube.com/watch?v=DfRHljKd8-s
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Main Solar system upgrade

Postby Doug Coulter » Tue May 01, 2012 6:19 pm

Well, the thing wasn't stable enough to suit me hung out to the ends of its booms, so we moved it:
http://youtu.be/8XCRlMhUlU4



This was problematic. Had to drag off some racks with the tractor. Had to get the truck in there - never got it quite angled right, pulled the thing towards the east end of the house, tried to turn it tounge to south, and almost made it before the usually unstoppable Honda Ridgeline just couldn't do it - garden dirt. So, we chocked a wheel and pushed it the rest of the way straight with the lawn tractor (this one's real serious as those go, though, hydrostatic drive, fluid filled ag tires). Hope I can get it pulled to the next spot, which seems like the plan at the moment. And oh yes, back when the rental is up - I'd love to have one, but the terms probably wouldn't suit.

Then I attempted to run and vid the thing - so so results, nice view and color, though. I am soooooo tired. Remember we had to clean up the mess we made trying it another way first.
http://www.youtube.com/watch?v=pAfmMUpAUaU

Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Main Solar system upgrade

Postby Doug Coulter » Wed May 02, 2012 4:12 pm

A little more progress - one full rack, 720w x 2, now up and in place, all the bolts tight. I'll probably add some trussing to that bottom half rack to handle the odd hurricane, but it's pretty decent - you can stand on things and no wiggles. As soon as I finish this post, I get to go up on the roof and do a bit of wiring. Having this one done means I worry less about disconnecting the other panels while working, as this is 1440 w, and is replacing 4x120, or 480 watts that were in that slot. Looks like I got it a little crooked, sigh - may have to leave gaps between the racks anyhow to be able to get in there to put in bolts and such. Had a plan, but I'm not crazy enough to stick with a plan that is showing too many problems either. Pix:
100_2322.jpg

100_2323.jpg

100_2324.jpg

100_2325.jpg


Wish it was miller time already, and it is almost 5:30, but just a bit of wiring and I've got power tomorrow as soon as there's sun...and then it's really miller time.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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