diy solar

diy solar

Solar Panels?

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Just make sure the panels fit your application legality wise. Sounds like you are off grid hobby, so it doesn't matter, but the dirt cheap panels have the labels stripped so they are not UL so you can't tie them into the grid.
We already have grid-tied solar for the house -- a 5kW system installed by Sunrun. This project is nothing but a small-scale effort to basically build my own solar generator for emergency use - SHTF stuff. It's nothing exotic -- but I'm trying to do this right from the start. If the power goes out, the panels on our roof are useless because they're dedicated to grid-tie and the system shuts completely down by design in the event of a power outage. It sure would be nice if the solar companies offered a connection off of the grid-tie inverter that I could tap into and use to charge up batteries if the power was out -- I could do a helluva lot with 4 - 5kW of solar power.
 
I "hate" to suggest these panels, because if Will mentions them, they will sell out like SOK batteries did.

330 Watts for just over $200. (5% discount for first order.) Blows the doors off the silly 100 W panels that I was buying when I first got into solar.

I've seen two produce 687 Watts this month on a partly cloudy day (so they had cooled down before the sun come again) in Phoenx, AZ.

I've seen them produce 450 Watts on a cloudy day here!


No sales tax. (Something about Arizona not taxing solar stuff.)

The only "down" side, is that they are expensive to ship ($120 for the first) because they have to go by truck.

But if you live in AZ (or nearby) just drive up to Flagstaff to get them.

(@AZRoadrunner : If you drive up there, I would like to buy two more. I'm near I-17.)
 
I "hate" to suggest these panels, because if Will mentions them, they will sell out like SOK batteries did.

330 Watts for just over $200. (5% discount for first order.) Blows the doors off the silly 100 W panels that I was buying when I first got into solar.

I've seen two produce 687 Watts this month on a partly cloudy day (so they had cooled down before the sun come again) in Phoenx, AZ.

I've seen them produce 450 Watts on a cloudy day here!


No sales tax. (Something about Arizona not taxing solar stuff.)

The only "down" side, is that they are expensive to ship ($120 for the first) because they have to go by truck.

But if you live in AZ (or nearby) just drive up to Flagstaff to get them.

(@AZRoadrunner : If you drive up there, I would like to buy two more. I'm near I-17.)
Thanks, pmikep. I'm all the way down southeast of Tucson -- even Phoenix is an all-day adventure. ;)?
 
OK -- so it's solar noon here in the Tucson area, totally clear and sunny. I took the one good panel I just bought from Eco-Worthy and ran the Voc and Isc tests. Voc is rated at 21.6, I'm measuring 24.5. Above the rating on that. Isc is measuring 10.02 amps, the rating is 11.89 amps. Is that slightly lower Isc of any concern?
 
We already have grid-tied solar for the house -- a 5kW system installed by Sunrun. This project is nothing but a small-scale effort to basically build my own solar generator for emergency use - SHTF stuff. It's nothing exotic -- but I'm trying to do this right from the start. If the power goes out, the panels on our roof are useless because they're dedicated to grid-tie and the system shuts completely down by design in the event of a power outage. It sure would be nice if the solar companies offered a connection off of the grid-tie inverter that I could tap into and use to charge up batteries if the power was out -- I could do a helluva lot with 4 - 5kW of solar power.
Yeah, that is definitely a short coming of grid tie systems. I didn't feel like paying $5k to hook into the grid so I ended up spending about $3k on solar. 2.25kw in panels, 6kw in LiFePo batteries and a controller. I estimate it generates about 8wk a day (maybe more), but since it is currently charging a 18v ryobi battery the rest goes into the ground :(
 
OK -- so it's solar noon here in the Tucson area, totally clear and sunny. I took the one good panel I just bought from Eco-Worthy and ran the Voc and Isc tests. Voc is rated at 21.6, I'm measuring 24.5. Above the rating on that. Isc is measuring 10.02 amps, the rating is 11.89 amps. Is that slightly lower Isc of any concern?
Maybe adjust the angle a bit and see if it goes up. That's 245w, no? I thought they were 195w panels?
 
If you buy a Victon Multiplus, you can set it to charge your batteries based on voltage or SOC settings. I use a timer to limit when the Mulitplus gets AC power in. So basically, I'm "time shifting." The timer disconnects the Mutiliplus in the morning, and reconnects it after peak APS hours. (8 o'clock pm.) This way, the solar panels run my equipment and charge up my batteries during the day, and if there's a need to top the batteries off at night, then the Multiplus kicks in.

Mine is only a 3 kW inverter (not 5 kW). Unless you buy their 48 V inverter. (But then it's only 230VAC out.)
 
I don't think that you can really know how a panel is performing until you hook it up to a (good) mppt and load it. For whatever reasons, I rarely see Vmp on my REC's. Nevertheless, as I posted above, they have produced more than their rated 330 W. (And that was without them being aimed at the sun! (Roof limitations.))
 
If you buy a Victon Multiplus, you can set it to charge your batteries based on voltage or SOC settings. I use a timer to limit when the Mulitplus gets AC power in. So basically, I'm "time shifting." The timer disconnects the Mutiliplus in the morning, and reconnects it after peak APS hours. (8 o'clock pm.) This way, the solar panels run my equipment and charge up my batteries during the day, and if there's a need to top the batteries off at night, then the Multiplus kicks in. It's only a 3KW inverter... unless you buy their 48 V inverter. (But then it's only 230VAC out.)
I am doing the same thing with mine. It has had to charge from the grid 2 times the last 7 or 8 days because of low sun.
 
So, based on the posts here, I just checked SanTan's website.

Wow, 335 W for $135? That's half of what I paid for REC's n half cells.

This deal seems too good to be true. Anyone?

 
So, based on the posts here, I just checked SanTan's website.

Wow, 335 W for $135? That's half of what I paid for REC's n half cells.

This deal seems too good to be true. Anyone?

I'm not merely going to make a trip to Santan. It's going to be a friggin' pilgrimage. Just two panels like that would be more than what I really need for my project. Which is why I might consider buying four and upping the game.
 
One thing that I noticed is the difference in the frame. The REC's have two cross bars for stability. Whereas the Hansol have none. And since the Hansol's weigh more, might twist more during installation. (And break?)

And they're not half-cuts, which I'm finding makes a big difference if any shading.

And the output isn't going to hold as long over time. Although since I'm 65, I won't be around to see 80%. So that doesn't really matter.

For the price, if one fails early, it's not much of a loss.

It's a closer drive than Flag. I might pick one up for grins.
 
We already have grid-tied solar for the house -- a 5kW system installed by Sunrun.......... If the power goes out, the panels on our roof are useless because they're dedicated to grid-tie and the system shuts completely down by design in the event of a power outage.

Where you live, have you ever suffered from a power outage? In the Phoenix Valley with APS, I don't even remember power flickering once in the 10 years I've lived here. Not so in any other place I've moved.

I wonder how much longer that can last as the state continues to shut down non-green coal burning plants without opening up equivalent "green energy" replacements, with the population growing so much.
 
Yes. The power went out for about two hours yesterday. (APS said a "major" powerline. Perhaps a traffic accident, since I don't think a construction company would be digging on a Sunday. Or the wind, since it was gusty yesterday.) I was mentally preparing to roll out the Solar Cart to power up the freezer and fridge if it persisted.

Last year, the power went out in the late summer for about 5 hours. Lightning. I did use the power cart for that.

After that, I upped to a Mutliplus, because, at the time, I was using the Giandel 2 KW (24 V) pure sine wave inverter that Will was recommending. But, to my surprise, the Giandel's cooling fans were coming on - for only a 240 W load, since it was our summer. (About 100 degrees in the garage.) I didn't have any confidence that the Giandel would be able to handle much more in the heat. Update: I should add that the Multiplus derates from 3000 W Continuous to 2400 W in heat. But at least they tell you that in their spec sheet. And even derated, it's more than the Giandel puts out. (Anyone looking for a barely used Giandel?)

And since then, I bought very quiet window AC to cool down one room in the house should the power go out in our 115 degree heat. (t's a 5000 BTU/5 Amp unit. (600 W) A reasonable load for my system. It's quiet enough that we could sleep through the night with a power failure if we have to.

Before that, about two years ago, we had an outage for two days. A substation went out. We had to drive 10 miles to another grocery store to buy dry ice to keep our food cold.

As our infrastructure ages, as the economy and politics become crazier, as our foreign enemies continue to try to hack our grid, and domestic enemies riot and break things, I think it's wise to have a smallish solar station for back up purposes. (I need to buy more panels next.)
 
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Where you live, have you ever suffered from a power outage? In the Phoenix Valley with APS, I don't even remember power flickering once in the 10 years I've lived here. Not so in any other place I've moved.

I wonder how much longer that can last as the state continues to shut down non-green coal burning plants without opening up equivalent "green energy" replacements, with the population growing so much.
Power outages are rare here in the Tucson area -- for now. However, I work in the power industry and behind the scenes it's overall nothing short of a volcano waiting to erupt. My consulting work takes me to power utilities all across the country and into generation plants, substations, and control centers. There are influential people and organizations in our country who seemingly have no clue what it actually takes to generate reliable, affordable electric power. They don't understand the physics or the logistics involved and they think the electric grid can run off of pink unicorn farts. As a result we, as a country, are walking on a tightrope with no more safety net and evil leprechauns are shaking the wire, trying to make us fall. I wouldn't classify myself as a "prepper"; rather, more of a realist. I'm all for "green" energy, by the way -- but the way the activists and politicians are trying to implement it is positively insane and will lead to rolling blackouts -- or worse. And on top of all that are the growing cyber security threats (that's my direct line of work) that our power utilities are having an enormous amount of difficulty keeping up with. It's a bad scene that's only masked by the fact that the lights are still on.
 
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Another plug for SanTan solar. I have used him and had no problems with a small order of 5 panels I placed a year ago or so.
 
Good to hear that I'm not crazy.

Yeah, we have let our guard down, since the electrical system has worked for so well for so long. I'm not so much worried about a huge CME taking the grid down - although that's a real possibility - as I am with all the other things that you mentioned.

I don't expect to survive long term when the stuff hits the fan. (And I expect that the plan is to have it all hit the fan at the same time.) I just want to buy time. I take care of an elderly widow, and she wouldn't be able to survive more than a day or two in the Phx summer heat without air conditioning. Without power, I can boil water in the sun for preparing food. But I can't make a room cooler without solar.

If we can get buy for three weeks (and fend off raiders), the situation will change drastically after that, and we'll have to re-evaluate the situation then.
 
I estimate it generates about 8wk a day (maybe more),
FYI, I harvested 3.7 kWh yesterday during the equinox in sunny Phoenix. That's using two 330 W panels, baking a bit in the sun (80 degrees F outside) and not aimed correctly. (Peak power yesterday only 530 W. (Continuous sun.))

Using my figures and mutliplying up for your array, I calculate you would be making 12 kW a day if you are similarly situated. More if aimed correctly.
 
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