Solar Stuff...

[Grant H.]

So, I got asked by a good friend to look at a couple "pre-made" solar solutions that he had found (apparently being sold at a "prepper" store here in CO), so he sent me the following link...

http://frontrangere.com/

For the love of all that is good and decent in this world, don't buy this crap.

Since he brought this up, and he really had no idea how crappy these were, I figured I would share here as well. I think most that are interested in solar on here have a better understanding that this, but maybe there are some that have questions.

Part of my job, industrial communications, involves sizing, designing, building, and using solar solutions that simply have to work. We have done everything from small 240W systems, all the way up to 15KW solar solutions for major comm towers.

After my discussion with him, I want to use what I know to help people that might want to setup partial backup systems, or even full off-grid solutions.

If I am off base here, and people don't have unanswered questions about solar, then this post will go away, but if people have questions, then I am happy to share what I know.

Not really prep/house oriented, but one of the smaller solar skids we have used a lot of - 270W at 12VDC, with 1290AH of battery backup. Provides 10 days autonomy for the tower without dropping below 60% charged on the battery bank.
https://c7.staticflickr.com/8/7635/27412539526_e193d5522c_z.jpg (https://flic.kr/p/HLmqXQ)0819142055 (https://flic.kr/p/HLmqXQ) by ARNEWB (https://www.flickr.com/photos/61071044@N08/), on Flickr

We have also done propane and diesel backup generators with ATS systems, so I can answer some questions there too.

[Blowby]

Thanks for providing technical information. I know a lot of members will appreciate this post. BTW, what is the cost of something of this size?

[ray1970]

I rigged up a small solar panel to charge my phone when I'm out camping. That's about the extent of my solar knowledge.

Pretty sure my company doesn't have any more solar stuff at any of our meter stations or microwave towers any more. Too hard to keep the hillbilly inbreds from shooting them up.

[Robb]

Post up a pic of your camping/solar charger.
Us hillbilly inbreds would like to see how that stuff is done.

[gnihcraes]

Interested in anything solar. I have panels on the house and a portable/panel setup.

[Grant H.]

Thanks for providing technical information. I know a lot of members will appreciate this post. BTW, what is the cost of something of this size?

This one in particular is C1D2 rated for hazardous locations in the oilfield which makes it more expensive (rated parts are pricey).

One that isn't C1D2 could be built for:
1x - 275 Watt Panel - $200 + shipping
12x - 215AH 6VDC Batteries - $1400 + freight, unless you buy local.
1x - Charge Controller - Anywhere from $50 (chitty) to $1500 (fantastic) - Don't buy the cheapest, Morningstar gear (PS-30, $125 on amazon, depending on your panel voltage and how many) works pretty well. Outback gear is my choice for home systems.
1x Battery box - The one pictured is $400, rubbermaid trunks work pretty dang well actually, and aren't that expensive.
1x Rack of some sort - could be built by ones-self for less than $100.

Total: $2000 assuming a rubbermaid trunk runs $150 (probably high), $100 for a rack solution, and expensive shipping for the panel and charge controller.

Given only 275W of solar, the 1290AH battery bank is a bit ridiculous. As I said that situation required that the batteries could last, and recover easily, through 10 days of no sun. If I were building it as a temporary power solution for preparedness, I would half the battery bank. That would save you $700 odd dollars.

[ray1970]

Post up a pic of your camping/solar charger.
Us hillbilly inbreds would like to see how that stuff is done.

Not going to happen. Sorry. The garage is a disaster right now and I honestly doubt I could find it. Too much going on in my life over the next several weeks.

[DFBrews]

I don't do anything with Pv
but my side gig is install and servicing of the hydronic liquid radiant heating side of solar and can offer some insite as well

[gnihcraes]

My portable panel is the Renogy 100watt one. Eventually I'll get a couple more, mount them to the camper most likely.

http://smile.amazon.com/Renogy-Watts-Volts-Monocrystalline-Solar/dp/B009Z6CW7O/ref=pd_sim_328_4?ie=UTF8&dpID=41rOZxjogoL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=0M57TSHBHSZP1P03SC6W

[Grant H.]

My portable panel is the Renogy 100watt one. Eventually I'll get a couple more, mount them to the camper most likely.

http://smile.amazon.com/Renogy-Watts-Volts-Monocrystalline-Solar/dp/B009Z6CW7O/ref=pd_sim_328_4?ie=UTF8&dpID=41rOZxjogoL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=0M57TSHBHSZP1P03SC6W

Before you buy more, at $1.4/watt, look at these guys. (http://sunelec.com/home/solar-panels/) Mono/Polycrystaline panels can be had for much less than that.

[Great-Kazoo]

This one in particular is C1D2 rated for hazardous locations in the oilfield which makes it more expensive (rated parts are pricey).

One that isn't C1D2 could be built for:
1x - 275 Watt Panel - $200 + shipping
12x - 215AH 6VDC Batteries - $1400 + freight, unless you buy local.
1x - Charge Controller - Anywhere from $50 (chitty) to $1500 (fantastic) - Don't buy the cheapest, Morningstar gear (PS-30, $125 on amazon, depending on your panel voltage and how many) works pretty well. Outback gear is my choice for home systems.
1x Battery box - The one pictured is $400, rubbermaid trunks work pretty dang well actually, and aren't that expensive.
1x Rack of some sort - could be built by ones-self for less than $100.

Total: $2000 assuming a rubbermaid trunk runs $150 (probably high), $100 for a rack solution, and expensive shipping for the panel and charge controller.

Given only 275W of solar, the 1290AH battery bank is a bit ridiculous. As I said that situation required that the batteries could last, and recover easily, through 10 days of no sun. If I were building it as a temporary power solution for preparedness, I would half the battery bank. That would save you $700 odd dollars.


Before you buy more, at $1.4/watt, look at these guys. (http://sunelec.com/home/solar-panels/) Mono/Polycrystaline panels can be had for much less than that.

So i see numbers like yours only higher, much higher thrown around. Exactly what would my $2K get me storage wise IF and when power goes down . The generators are out of gas and propane back up runs out?

We've had an interest in solar as secondary supply. Unfortunately, when the monthly cost is more than our mortgage and something we'd never recoup savings wise. It's hard to justify spending anything.

Would it be nice for our next home, sure. Again cost are still higher than the results.

Please enlighten me, and others here.

[HoneyBadger]

Grant, thanks for sharing the good info and links. [Beer]

[gnihcraes]

my homemade junk;

https://lh3.googleusercontent.com/El2xY4TUbnl7lLUgTTFKTsccXMNvnZJ6evbtJ9DorIOoRId7yh x3bW1x62pXIQkXRBrdwZp0ivCu2iPJj35mj7vCYRgiKU3XBPQ6 dz3LXNkFPegtKqM9Q-jO-X47fwplaNtHrKh_8A-NqFXJh9IGYrlKUj9r_Zwa5gazLdWxQArXB1t_ZOvGcr3T44gIN nZxQcMqDcIYxBuwf3cSaUmvbgxT7cGFhr73MoHbOFZPh8kqJRX yfT6Ok6DvlMnuwdWtHF9vZCHb5xbhhIwJt2ityL1tEKiSkftd8 g586cNNlhzSRSpPvOfTNW7uM7_AAI0jvZnw7CLIBax2fLvXpzF fDMkFpU46MjosCQTDE0ws3TdWGCHfMUjKI-GcD0L6SeEBAETX5o73uD-cJNNK38j5kkpwRQSnNHpsHFtye88LmsyLcPKVT5jQh31NoY8qB 1beAmF_mS7WtT_EcV5yKdtLIsSg03xwt1kivCzhMhr9RlnOnCB DIS3jjUrY2MnyFPrLMSUmehDoiOe_1qPPW3NnGb76gh3l2KUvh HOK3KvIZDfwE1bwAbq608DGbFJMXy0Af77vblfmMnCpv7steVZ tkC6KQsWDEkZw=w1769-h995-no


Installed into a Rigid portable toolbox setup. A work still in progress.

88ah battery.


https://lh3.googleusercontent.com/wdWTkyYtFLNNfhD_D-9SMEXj7-2mclQ37IPtvhFKlXYxWj3tv4-clskbMnXnk9b6jv_3sf3LbERihWDK9R0E5Gerk4R7TMSHJgRPA 5oZ_z3D9vFLbkpcevZf7VbkMseM1I9a5WSn5rIjLKYPBQ7gEMl JFXh6B6xD72JPFTND6Vd0KId2_pq-lfWgTYTGqeH7PW3nJl_kp3Gl9HI7S3jf9O67s-9If0suoOm1bFCKo2PPG-HVCoVUYpV9suTjUaOy7RyqagYO43sYA-wy88dOMfE_YZIqFbyHkPh7lis7I5s5RCoDJ13o2eOO6MmKc1zI cRXU8y2y3LmVcGb-OH2WsdHAAb5K18bfXMlzgxLNiAY30b-ZjHkTsNzGuccV1yaLqVJmeCtWl1Ypi7-_G4psxnZZIvfttf1KFQJMiEyLNyobYT6TBr926Li_2VmrTsecS zfkkDmE9XzF5VG7TdzQh-CEVUoyc4CDEFZkN4hksDLrP3DjXn2_QtNbOFRR13N6myCBhCK_ ALZdx9p1EBQxUYxIcPDYdC8pRQX1zSJqAvURgXi3HGAvPHsOQu 3o3SP23ABSdlgxi_3VPnmsoazVEDqeTh44c6S-=w1769-h995-no


controller is cheapo, but will upgrade sometime. Still looking for a reasonable cost pure sine wave inverter.

[killianak9]

Following

[Grant H.]

So i see numbers like yours only higher, much higher thrown around. Exactly what would my $2K get me storage wise IF and when power goes down . The generators are out of gas and propane back up runs out?

We've had an interest in solar as secondary supply. Unfortunately, when the monthly cost is more than our mortgage and something we'd never recoup savings wise. It's hard to justify spending anything.

Would it be nice for our next home, sure. Again cost are still higher than the results.

Please enlighten me, and others here.

If you are talking about what I will call "retail solar", then I completely understand how you were getting numbers much higher than what I am talking about.

It depends on the type of system you are looking at:
1. Grid Tie
2. Off Grid
3. Emergency

1. Grid Tie:
Generally, these are the most expensive, even though they may not have a battery back up. The cost comes from permits, dealing with the Electric Power provider, carrying grid tie insurance, etc... As mentioned before, lots of current grid tie solutions (Solar City and the like) don't include battery backups, so they do you absolutely no good when the power is out. Some will actually power your house during the day, but if it's cloudy/snowy/dark/etc... You get no power.
Depending on the provider you can add a battery backup, but the batteries are the most expensive part of a solar solution any more.

2. Off Grid:
These are done one of two ways... With Permits, and without. Permits for off grid systems aren't hard to get, but they add to the cost.
Off grid can be done pretty inexpensively, and if planned out right, can be done in phases when money is available. For my brothers house, we did 6KW of panels to start, but we only had a 1000AH battery bank to start. He has since grown that, and is looking at some other options, but only as money is available. What we did was hang a second breaker box next to his existing breaker box and move certain circuits (based off of load requirements) to the new box and then tied that box to the inverters from the battery bank. As the batteries have been added, we have moved more circuits to his solar. At this point, a few of the larger 220V items stay on grid power (welders, mill, lathe, CNC router, etc...), but the rest of the house is on solar.

3. Emergency:
This would be more like the skid I posted a picture of, when thought of from a prepping standpoint. It's mobile, depending on size/batteries it can power critical items like comms, food storage, and others for several days without sun, and given the appropriate panel sizing, can then recharge quickly when set into the sun.

For that skid, a standard deep freeze will pull 5-6A (@120VAC) when running. Since you will have to have an inverter to get 120, lets assume it pulls another 2-3A for inefficiencies (high, but I always tend to make my assumptions high for a margin of error). So that means it will pull 9A while it is running, which means that if it runs for 24 hours, we will have a total draw of 216AH. So, a 1290AH battery bank, without breaking the 50% discharge point, could run your deep freeze for 3 days, without any sun. A more reasonable battery bank, at 645AH, would only run it for 1.5 days without harming the batteries.

Now, you figure in the panels, which 270-275W of panels (@12VDC) will provide 22.5A for every hour they are in the sun. I usually build my solar calculations off of 4 hours of sun for this area, which is low, but it leaves another margin of error built in. Obviously, 4 hours at 22.5A won't replenish 216A, so we would need a larger panel array. An additional 275W would add $225 (assuming shipped) to the cost. That means you would get 45A for every hour of sun, which means 4 hours would replenish the current used.

So, for $2225 (or roughly that), you can have an entire deep freeze of food that will stay frozen, even if the power is out for weeks.

[jerrymrc]

My second garage is now solar but on a smaller scale. I used to build my own panels 10-12 years ago and did nothing but dry camp. Just a game of adding it all up and learning to use it wisely. My Camper was set up with just a little over 100W of panels but carried 570AH or so of batteries. Built my own LED lighting as well. Never ran out of power. Nice update on the current situation Grant.[Beer] I am also a fan of having at least a 20A charge controller put away along with some other items just in case.[Flower]

[offgrid]

Given only 275W of solar, the 1290AH battery bank is a bit ridiculous. As I said that situation required that the batteries could last, and recover easily, through 10 days of no sun. If I were building it as a temporary power solution for preparedness, I would half the battery bank. That would save you $700 odd dollars.

Ya, a single 275W panel with a 1290AH battery bank is silly ridiculous for preparedness. For a small solar solution for preparedness , I too would half the battery bank, also add another panel and a inverter. If someone was to put together a system like this, no reason not to use that available power every day.

[tbetty]

was looking at this for sometime in the future in order to possibly power an off grid cabin, thoughts?
http://www.earthtechproducts.com/xantrex-powerhub-1800-with-3-panels.html
doesn't look too bad, but then again I know little about this stuff!

[Irving]

Like most retail products, you can build your own, specialized for your specific needs, for probably a quarter of that price. Think of it like building a junkyard turbokit for Civic compared to buying a full kit from a speed shop, only without the junkyard parts.

[Wulf202]

You could piece together twice the system for half the price by sourcing each component separately.

Or some kind of car analogy.

[Grant H.]

was looking at this for sometime in the future in order to possibly power an off grid cabin, thoughts?
http://www.earthtechproducts.com/xantrex-powerhub-1800-with-3-panels.html
doesn't look too bad, but then again I know little about this stuff!

That wouldn't be a bad little system to run a few small things with, my only complaint with that source of it is that I can buy the same parts (different but similar panels) for $1600 on Amazon right now, no shopping around to bring the price down.

That price can be brought down by sourcing some of the parts differently.

1. Instead of 2 12VDC 100AH batteries, get 2 6VDC 215AH batteries for just over the cost of 1 12V/100AH battery at Batteries Plus. They are golf cart batteries. Better life cycle expectancy, more storage (marginally), and cheaper.
2. The Xantrex name isn't bad, but there are equally good and better items out there for the same money.
2a. The Powerhub thing? Fancy replacement for an inverter. I can get a Bestek (reasonable quality, use one in my work truck everyday) 2000 Watt inverter for $180 on Amazon.
2b. Charger. Their chargers are fine, they work. I see them used frequently in the O/G world for AC charging of LARGE battery backups. The price point for this one ($100) is pretty hard to beat.
3. Shopping around for 300 watts of panels may very well yield a significantly better price. $.50/watt isn't unheard of right now.

So, built quickly as I would do it?
$330 - Panels: https://www.amazon.com/ECO-WORTHY-Polycrystalline-Photovoltaic-Battery-Charging/dp/B016EQFD8W/ref=sr_1_4?s=automotive&ie=UTF8&qid=1477455440&sr=1-4&keywords=100%2Bwatt%2Bsolar%2Bpanel&th=1
$100 - Charger: https://www.amazon.com/Xantrex-C35-CHARGE-CONTROLLER-35AMPS/dp/B000OYZE58/ref=sr_1_1?s=automotive&ie=UTF8&qid=1477455141&sr=1-1&keywords=xantrex+35+amp+charge+controller
$180 - Inverter: https://www.amazon.com/BESTEK-2000W-Power-Inverter-Outlets/dp/B00T93K9KU/ref=sr_1_4?s=automotive&ie=UTF8&qid=1477455566&sr=1-4&keywords=2000%2Bwatt%2Binverter&th=1
$200 - Batteries: https://www.batteriesplus.com/productdetails/sligc110

Total: $810+tax/shipping depending on where/when you buy. So around 35% of their price!
Just my thoughts!

[Fentonite]

Reviving the old solar thread. I have a tiny cabin (ok, a tuffshed) on a mining claim in the mountains. I just finished putting in an equally tiny solar power system to run multiple 12V LED lights, a fan, and a charging station for portable devices. Two marine batteries in parallel, a 30W solar panel, cheap charge controller, automotive fuse block, and a homemade switch panel. Seems to be working just fine so far for my needs, time will tell if it holds up. I really know nothing about this stuff, just winging it, so I'm sure I did some things wrong. Fun project, either way.

http://i841.photobucket.com/albums/zz339/fentonite/ADB75350-5C1C-4F0B-A949-754A5EF8245D.jpg (http://s841.photobucket.com/user/fentonite/media/ADB75350-5C1C-4F0B-A949-754A5EF8245D.jpg.html)

[Grant H.]

Doesn't look like you did anything wrong to me.

If you find yourself looking at a slightly bigger panel, look at an MPPT controller first. For a little additional cost, I saw a 25% improvement in solar production when using small 10W rated panels (went from 8 watts with a non-MPPT to 10.5 watts with the MPPT).

Some people forget that small solar installs can be just as good/beneficial as big ones. I have LED lights in my backyard shed that I did with just a small solar setup, and it's great. I didn't have to trench and pull power, and being low voltage no permit was required!

[Fentonite]

Googling "MPPT controller"...

[Grant H.]

Lol.

Sorry, Maximum Power Point Tracking Solar controllers.

Basically they hold the solar panel to a lower voltage (a 12v panel is around 18v open circuit) and convert that extra power to current instead of peak voltage. Essentially just more efficient.

[Fentonite]

Thanks - that's makes more sense than what I was finding online. So, could I use a 24V, 30A panel with my 12V setup, if I had an MPPT controller? I have a 24V panel just sitting there, could swap if it would be more efficient and not fry my batteries.

[Grant H.]

Thanks - that's makes more sense than what I was finding online. So, could I use a 24V, 30A panel with my 12V setup, if I had an MPPT controller? I have a 24V panel just sitting there, could swap if it would be more efficient and not fry my batteries.

I'm guessing you mean 24V 30W, not 30A. Otherwise that's a big damn panel...

Yes, a 24V panel can be fed into a 12V battery bank with an MPPT controller.

As far as running both into the same battery bank, yes you can, run the panels and controllers in parallel.

[Fentonite]

Yes, 30W, sorry. Cool, thanks for your advice! Much appreciated.

[Grant H.]

No need to apologize.

Happy to help. Like I said when I started this thread, I've done a lot of solar, for work and for fun, and I'm happy to share information and suggestions.

[Grant H.]

So, I got bored today. Couldn't be climbing towers or pouring concrete, so I started on a few little solar projects that I've been planning and collecting for.

1. Portable solar electronics charging box.
A couple weeks ago, we had a power outage, and my wife called me while sitting in her car to charge the phone. So, I built this as a first round of a portable solar solution. I still need to add the 12VDC to 5VDC USB charging port, but that's on the way via Amazon.

I also have some supercaps coming from china, and I will play with using them and a buck/boost converter to replace the batteries. Supercaps can be drained to zero and brought back many thousands/millions of times, so they will will always work. They can't be killed by draining them too far. They also allow me to eliminate the solar controller, which makes it all the better. Once they all show up, I'll update this project to show what I'm planning.

This is a 10W 12VDC panel, and 2x 7.5AH 12VDC batteries with a Morningstar Sunsaver PWM controller.

https://c1.staticflickr.com/5/4166/33937658873_8d9842fbed_c.jpg (https://flic.kr/p/TGXnBx)0517171909 (https://flic.kr/p/TGXnBx) by ARNEWB (https://www.flickr.com/photos/61071044@N08/), on Flickr

[Irving]

Can you direct me to a place to get a box to hold the battery for my solar project? I'm putting a panel on the roof of my van. I thought the best place to mount the battery would be under the hood, so I don't have to worry about venting it. It'd be a lot easier to do if I could mount it inside the cabin though. Any thoughts on the importance of the venting on a small battery? It's an 18AH battery.

Also, I came across this video the other day and I thought it was interesting.

https://www.youtube.com/watch?v=eJ1OztoGprU

[Irving]

Never mind about the battery thing. I just realized how stupid easy it would be to mount inside a box and vent to the outside. This may change my whole plan...

However, I'm pretty shaky on running the numbers to make sure that everything is compatible with each other as far as size of battery vs size of panel.

Can you talk a little bit more about what you expect to be able to charge with your system? I've got a 50W panel and an 18AH battery and I have no idea how long it would take to recharge the battery, or how many devices I could charge at the same time.

[Grant H.]

2. Solar Power solution for network gear in my house.

A friend of mine called and offered me 26 7.5AH 12VDC batteries for a great deal, since he got them as scrap when he refreshed a set of UPS's for one of his customers. They all tested at 12.3VDC or higher, so they are all good.

My plan is to move my fiber modem, router, switch, and access points to solar. The fiber network is all on emergency backups, so it all stays up/functional even when the power is out. So, if I keep all my gear powered up, I end up with internet access even with power outages.

Pointless? Sort of, but I couldn't pass up the deal on the batteries, and I don't have a better use for them right now.

So, with 26 batteries, I used 2 in the previous project, and used the other 24 for this. I wired them into 6x 48VDC cells, and will then use a collection of smaller solar panels wired into 48VDC arrays. I spotted an auction on eBay the other day for 48V specific controllers, and gave $15/ea for them, hence my 48V plan currently.

Morningstar PS-15M-48V - Used, but cheap/functional on eBay, so why not???
https://c1.staticflickr.com/5/4187/33904415814_eab61baccb_c.jpg (https://flic.kr/p/TE1ZBm)0518171949 (https://flic.kr/p/TE1ZBm) by ARNEWB (https://www.flickr.com/photos/61071044@N08/), on Flickr

Batteries placed into boxes temporarily, wired together to put on a trickle charger till I get it all finished...
https://c1.staticflickr.com/5/4165/33937659173_55524703e8_c.jpg (https://flic.kr/p/TGXnGH)0518171932 (https://flic.kr/p/TGXnGH) by ARNEWB (https://www.flickr.com/photos/61071044@N08/), on Flickr
https://c1.staticflickr.com/5/4267/33937659703_0991735664_c.jpg (https://flic.kr/p/TGXnRR)0518171937 (https://flic.kr/p/TGXnRR) by ARNEWB (https://www.flickr.com/photos/61071044@N08/), on Flickr

The cabinets were free to me when I replaced them with metal boxes for a customer, so that's why I used two to start, but when I get them mounted in the backyard, I will condense them down and have the controller and the inverter mounted in one of them.

I'll keep this one updated as well in case people are interested.

[Grant H.]

Can you direct me to a place to get a box to hold the battery for my solar project? I'm putting a panel on the roof of my van. I thought the best place to mount the battery would be under the hood, so I don't have to worry about venting it. It'd be a lot easier to do if I could mount it inside the cabin though. Any thoughts on the importance of the venting on a small battery? It's an 18AH battery.

Also, I came across this video the other day and I thought it was interesting.

https://www.youtube.com/watch?v=eJ1OztoGprU

These guys would be a place to start looking for enclosures for in your car. https://store.solutionsdirectonline.com/storefront.aspx

What dimensions do you need? I may have used ones that I would sell cheap.

The video is similar to what I want to do with the supercaps in my solar usb charging setup. His solar controller makes the supercap pack very limited, and he acknowledges that in a different video. If you size the supercap pack to accommodate the VoC (Voltage, Open Circuit) of the solar panel (will be ~17-18VDC on a 12VDC panel), then you can eliminate the solar controller (less cost, less current draw), and it starts charging as soon as sun hits the panel. The use of a buck/boost DC-DC converter allows one to extract a lot more of the energy stored in super caps because it allows you to use 3VDC to 20+VDC out of the pack.

[Irving]

I find all this super capacitor stuff very interesting, and wish I understood it all better.

Thanks for the link to the enclosures. I think I may have to post up what I want to do in the DIY forum and make sure I have a system with compatible components before I move forward with anything, just in case I decide to go with a different sized battery, panel, or both.

[Great-Kazoo]

Grant, thanks for the nice write up. This project seems more reasonable for the entry level person.
Knowing you barter or buy used when possible. What price point for those who don't know how to barter [Beer] would one be looking at for your finished project ?

Then there's weight of unit vs portability, or will this be a stationary one ?

Of course the final item would be footprint. Working with limited space could be (for some) a deal breaker.

[jerrymrc]

I used cast-off AGM batteries as well. Portable X-ray machines use a bunch and they have a mandatory replacement of 24-36 months. The ones I got were 29Ah each and I used a bank of 10 for 290Ah of capacity. 100 watt panel and a charge controller are used in the second garage. I have 3 strings of LED's that light it all up. Under normal conditions the panel put out around 4A and the lights draw about 5A.

[gnihcraes]

@ Grant H,

any recommendations of DC/AC Inverters? I need a good pure sine wave one. Difficult to find anything that seems decent yet reasonable in cost.

800 watts minimum, yet I don't need much over that. (startup requirement is 800 watts of a device, run time is much less than that I believe)

[Grant H.]

Never mind about the battery thing. I just realized how stupid easy it would be to mount inside a box and vent to the outside. This may change my whole plan...

However, I'm pretty shaky on running the numbers to make sure that everything is compatible with each other as far as size of battery vs size of panel.

Can you talk a little bit more about what you expect to be able to charge with your system? I've got a 50W panel and an 18AH battery and I have no idea how long it would take to recharge the battery, or how many devices I could charge at the same time.

Sure. I'll run the calculations for my internet gear as an example.

Currently, (I have new gear on the way that is more power efficient/better technology anyway) I have 2 devices that I want to power to keep my internet service up during a black out:
1: Fiber Modem
2: Asus Wireless Router

Start with looking at the devices to see what they require as power input on the back/bottom:
1: Fiber Modem - 12VDC @ .4A
2: Router - 19VDC @ 1.58A

These numbers are usually, 99% of the time, the "worst case" numbers for those devices. If you want to, you can get a power meter and plug them in and see how much they actually draw on average and build against that. I don't like that method, so I always use the "worst case scenario" and pad that just a little.

Convert them to watts: VDC*A=Watts
1: Fiber Modem - 12*.4= 4.8W - I rounded this up to 5 Watts for my calculations
2: Router - 19*1.58= 30.02W - 31 watts - Power hungry little bastard...

Add them together, 36 watts, and multiply by 24 to get the total number of watts you will use in 1 day. 36*24= 864 watt hours per day.

So, the total consumption that I need to offset with panels and sun is 864 watts per day. If we assume we only get 4 hours of "full" sun in the winter, again the worst case scenario, that means we need 216 watts of panels to provide each day worth of usage. Now, that number has to be larger, because if you go days with less sun, the batteries will get pulled down to make up for the lack of solar. For my own non-critical projects like these, I tend to use 125%, so it would take 4 days of full sun to make up for 1 day of no sun (black blanket over the panel type of no sun). Even on really bad days, the panel will still generate some power, so I build on the smaller size. When I am building for a customer, and it's critical, I usually use 150-200% on the panels to make the system recover as quickly as possible.

So, 216*1.25= 270 watts of panels for this system. Part of the reason I am getting much more power friendly, albeit better network gear!

On to the batteries:

We know we are using 864 watts per day, so we can divide that by the voltage of the battery bank we are using to find out how many amp hours we need in a day. Since I decided to screw around with 48V on this system, we divide by 48.

864/48= 18AH per 24 hour day. Now, we have to account for batteries inability to drain to 100% and recover, so I multiply that by 2 so we only reach a 50% discharge level. Less discharge is better for lead acid, but 50% is safe.

So now we know that I need 36+AH of batteries to run my internet gear for 1 day on batteries alone.

Multiply that by the number of days you want to be able to use the gear without sun (autonomy), I said 3 days in my case, so 36*3= 108AH. I didn't get anywhere near that in the cheap UPS batteries, which also drove my decision to get new/better/less power hungry network gear.

So, that's kind of a rambling explanation of how I calculate solar numbers.

As for your 50W panel and 18AH battery, your 50W panel will provide just over 4 amps with full sun. Now, mounted flat on the roof of your van, it will have full sun for a short period each day during the summer, but significantly less during the winter. It will still likely be plenty to make up for a 50% discharge of your battery on any day.

As for how many devices you can charge, if you figure you have 9AH to use out of the battery, then with no sun you can charge up to 9AH worth of devices, and the battery will still recover when the sun comes up. I know it sounds dumb to say that that way, but you can usually find out how many mAH's your phone/tablet/etc battery actually holds. My LG G3 has a 3000mAH battery, that's only 3AH. You can probably safely plan on a full recharge of your phone being less than the actual battery rating, but for the margin of error, I just use the full capacity. But you could charge 3 phones from dead to full without hurting your 18AH battery. As for how many devices you can charge at one time, that is more a function of the 12VDC-5VDC charger that you choose. Your standard 2.1A USB charger is going to be 2.1A @ 5.1-5.4VDC so worst case, that's 11.34W, which on the 12V side is only .945A. Most batteries have a spec for max discharge current, but its usually in the dozens to hundreds of amps.

If the sun is up, then the solar controller should charge the battery to max capacity, then shunt any solar current to the load output of the controller, which is what you would want to wire your charging ports to, so then you can charge even more devices because you aren't pulling on the battery.

Hopefully my rambling helps.

[Irving]

Very helpful, thank you. I'll expand on where I get confused later when I have time.

[Grant H.]

Grant, thanks for the nice write up. This project seems more reasonable for the entry level person.
Knowing you barter or buy used when possible. What price point for those who don't know how to barter [Beer] would one be looking at for your finished project ?

Then there's weight of unit vs portability, or will this be a stationary one ?

Of course the final item would be footprint. Working with limited space could be (for some) a deal breaker.

I'll have to pull a few things together for pricing, but size is pretty easy for me to get you. Weight will be something I can get later today. The box and panel are on the roof to charge with what sun is available today.

The end game with this as a portable unit, will be to put a bracket on the solar panel and lid of the box that allows the solar panel to fold down flat when stored, and then hinge up, and have a prop/support to hold it at a 45° angle when in use, thus making the foot print of the whole system smaller and one unit when in storage.

The box is 13"x11", and with the unistrut on the back is 7.5" tall. The panel that I have is 16"x10.5"x.75", so it's not terribly large. As you can see in the previous photo, there is plenty of room for more batteries to make it a larger capacity, but this was just to keep these batteries tended for now, and proof of the concept.

Weight will be 2 very different numbers between the lead acid batteries, and the super caps once I try them. Super caps are significantly lighter than normal SLA batteries.

This picture is sort of my concept of the hinged panel, but this is just temporarily set on the roof.
https://c1.staticflickr.com/5/4192/34756908125_3b15d0fce1_c.jpg (https://flic.kr/p/UXmeSD)0519171039 (https://flic.kr/p/UXmeSD) by ARNEWB (https://www.flickr.com/photos/61071044@N08/), on Flickr

[Erni]

If you make it portable I would suggest 2 panels so that when you fold them the glass is protected. You may need to add another cover on the back of the out facing panel to protect whatever is back there. (Diodes, wiring, whatnot)

Very nice.

[Grant H.]

@ Grant H,

any recommendations of DC/AC Inverters? I need a good pure sine wave one. Difficult to find anything that seems decent yet reasonable in cost.

800 watts minimum, yet I don't need much over that. (startup requirement is 800 watts of a device, run time is much less than that I believe)

I've been doing a lot of poking around and reading about reasonable chinese inverters, and it seems like a lot of them are decent machines, but they are less efficient than high end gear (Outback Power for instance).

I don't know if you want the hassle of creating 220V then using a breaker panel to drop to 110, but the EPEVER inverters actually seem to be pretty decent from the reviews that I have been seeing/reading.

I know that the EPEVER MPPT solar controller is actually a good value if it supports the battery voltage you are running.

Samlex and Aims are also relatively decent as per the reviews I have been finding, and they have a lot of different models that should fill what you need.

[gnihcraes]

I've been doing a lot of poking around and reading about reasonable chinese inverters, and it seems like a lot of them are decent machines, but they are less efficient than high end gear (Outback Power for instance).

I don't know if you want the hassle of creating 220V then using a breaker panel to drop to 110, but the EPEVER inverters actually seem to be pretty decent from the reviews that I have been seeing/reading.

I know that the EPEVER MPPT solar controller is actually a good value if it supports the battery voltage you are running.

Samlex and Aims are also relatively decent as per the reviews I have been finding, and they have a lot of different models that should fill what you need.

Thanks. Not looking for a panel, just a portable inverter large enough to run the wood pellet stove and a 12 volt deep cycle shown in my previous build^. More of an experiment to see how long it will last. Might build up a battery bank to support it for a longer duration.

[Grant H.]

Thanks. Not looking for a panel, just a portable inverter large enough to run the wood pellet stove and a 12 volt deep cycle shown in my previous build^. More of an experiment to see how long it will last. Might build up a battery bank to support it for a longer duration.

Makes sense. I would go browse through Samlex and Aims offerings and shop the part number you want around for the best price.

Side note, do you actually need pure sine?

What, I suppose the pellet stove needs pure sine wave for timing purposes?

[gnihcraes]

Makes sense. I would go browse through Samlex and Aims offerings and shop the part number you want around for the best price.

Side note, do you actually need pure sine?

What, I suppose the pellet stove needs pure sine wave for timing purposes?

Not sure it needs pure sine, but it does have some control boards that I'd rather not fry. Auger motor and blower motor can't take much power, it's the igniter that chews up the initial load. thus why it says 800 watts required.

Looks like there might be some Aims on amazon used for reasonable price.

[jerrymrc]

Not sure it needs pure sine, but it does have some control boards that I'd rather not fry. Auger motor and blower motor can't take much power, it's the igniter that chews up the initial load. thus why it says 800 watts required.

Looks like there might be some Aims on amazon used for reasonable price.

My backup for my pellet stove had 240 Ah of AGM batteries tied into a 700 watt UPS. the load running the blower and auger was 120W running the blower and another 55 or so for the auger. I ran it once for 5+ hours on battery and it was above 50%.

[gnihcraes]

My backup for my pellet stove had 240 Ah of AGM batteries tied into a 700 watt UPS. the load running the blower and auger was 120W running the blower and another 55 or so for the auger. I ran it once for 5+ hours on battery and it was above 50%.

awesome. good to know. Someday I'll quit being lazy and measure it all while running. :)

[Irving]

Saw some solar shingles for the first time today. Snapped some pictures for you guys. This is over in the new Midtown development over at 60th-ish and Pecos-ish. Special note: That is about 1" hail spatter you see. Totally destroyed the roof (mostly) but the solar shingles looked perfectly intact.
https://lh3.googleusercontent.com/tX6NsCobwy252X09htpcwth30opPDWb9ZM_PpqOM9Rc2RGe5u6 oUy2JJBluaImCl1UZ4BJzxhhRwzddJKzJhXhvnU7VhDfMmHTrQ F9OhrVZ3bNT7MAd-yqDIzRMdG9ToIU8eoe8CDZX51uL4aX-PF7OzgfFffD7PVFhF2jRu-TJU6h5BdBaCz9_deOx-FCmnoiurL_02hFjmase8aUqGXQ1n7SWfdo_6gIU0tCXvCcVqYa yTpYr3vtMSNdgMQWXZLXbJHA_T2-SCLObmiwsF73iUA6yUV0K4W8ZqUQhGmAfkp18ngqXf8pXj_R2V Sdyta5PZQ2jtUINnyb0aaFcmnkZ8aTEyxr1F7jvl_WLf6-nNO6pIXcKdKv4bma009nptSV1MsO-7a8Lkfw1BDH6_Hpx7Hlf_0rRmKJsP_9y6voC46Ld1AMyS_ysCk DdqhxiNYMFbBYbbJJGRWBnKTfJyPbnLAvXp5mBBxL0sNrTbjYj SiqL_oN83ofu0l-RI3xCmFtBb2xQ3ML1DpswTxuO7nAKZyKpE6-MnAXAejizmZWcRk-i2cbOsZ0U7uPW3tYk5SIrfDy6LoVF269LRZe6PUTX7MVkvYD_g 55Exwh6BjOdq1mCBDwwJsU0zLWJYpVEsvbqVA4mFPFkp2li07r fj2Yr6l7hUDDdwW5b-lKdO6xg=w1634-h919-no
https://lh3.googleusercontent.com/eJVgAYSm8LeudbyeanfhcEkjxWKw-LWHFwvp2bgR5ZQp60s28mqfY0vu1RD5Yekop_87XOLAOvvn3PN b3odp5mpGR6G-SduqAHpS8CO0EMvh8jfSq1OW1fSAy55cYsnceiUWeAcCcGPt8W gEbbfpbDRlQwhVStxItxrJQrV659j7j_zzip7OqPyMkHUPPEiR JiPKHF5hnGCKWU0BgF_gxH6DE4zMMqeVkCMK1Xij85hQY2fyJp Ca_jfJbYO6NgaLvpbZdaJIJSUWvgswT5h0opjbIFOTc1ABcG08 8JMSlYOrDt_46OOdbGmoA5vufGsWtsyxK-KirPQyvAz-YE1Ak6aC4UVZLpjffoKX4G2wUWUZyxK-qf5zwKtCaLQWQQnbCbwYHjBuhx7XHXc_wVcdtMEq0wn0RN4ocO uXlvG20o1hWcpo9obfM0eG_13E_W5rX3Dl62-Igj6Y0VHIGTAqWbwQnqEs5kCDOzTVKEhEY06Z7MRyTcLgKqQoC Q6vFw6WOO-FWAtDAJ7vDRz-8UhHC1_7ZkqxnCspIRA91i6pOfcJqgcFPrcbxZDnkEYe-N4hJh9G80E9jWpr4OHBRuXGnRQCXIYRltelqhhYySwmJehHHt5 d6RXuFGtsEjwh9QGCHZvQqHC2s2LigRFnnuBsMu51JEulxZxB4 JQg6ENZzzs=w1634-h919-no
https://lh3.googleusercontent.com/OsYIoCwCqgSWTeibFV9UzAp-ukmSC1bMmUOxPL9G8fi0J4KfpFJJ6TRmyHFCp_j8zeGqkJdEry yNNTeUADNo959iiD3CAT-rYnJpomVAb9mOAVuhoc9uiG_O7w3EGkMkEARaWj8osBmxBpAbz 9bgtN9cZkzhmcGVxm8R5DFGbH8xPf4MmMxPjaNAwufoHdboCRX fWjcO8ssqOL7fUDHmcyeSwvZgHW7gP0QH0xebQtBRktM2RHD3N 8Kl-WvytkwVWFQSKuljhM03bzY3hmY4dwNjUu81uy_vKp_71G-Vrn39P9h4iNl1qKanWDPtD_y9IDpF3P4nZiudWgQLoEm0EgGJH 9jWncvMy7vFn7NQQPvdzVsrLCvr76k1ftegcHFUA9xSFwAQfXp 05eWcNKMORgX1q9gnp3dmGeWWxEbe6bIE9SYL18FutmIUJwL7c iesf5fZ__8TOudqhm2VJ2UynSKaXrILNTsd3QaOFq54kgn2ruz ghj7Uc8oE9WAF42Dws-XuG1NDnMwdNqyLK5i6mRZkpf8SdXfVAJOjrZ5hiKnX3QR-RE0LDucL-E3wzImRBrE_n6yLa4Ew_R_2BYFFGHzW3UUHdHRxR8H9gMmXxyY wE-aNh2ow9qKEDz0TCl0erhGTF_Zec8tl7-wGDDMtP5G4p6EWvf-X82l_xXgghUM=w1634-h919-no
https://lh3.googleusercontent.com/5o2e_FPSMGrjbcEHwk8Z1dUQbQsyN2q9wvuwnvLZ30Khla-xrfkBZKVod4KQU2pwAsESnNOto3IXIaN7hQ4Rt8Eq3rg04Mzfu v3DIVthMgeZSZRltZdvdMmvxcxytbMbLzu4BQ2JEhDsplAfwIX ENESSFleT6GIozjb9qav2PPDzMfOidYgSx8-NofXDcPTahvdpKcpkJtwsTUUXGZUzIioEzTy-Xo-4YgsuATOxbMeLZzeSBl91KWL_9KwnN0yE42ZaypsAWZNSsKQYA 45BHP9Wf_mEqHDyzqvpiVXYznbvZIt0qBd4lj8ygaUFZ8Peshn P0qxEcv8zFZvKFdAD4GFb4zWp8cX_od_rNoDxo4YFF5q3LY2_h oVEVRiKhE4VDz93ECDWjEqBOs_lWnv1eDmCZ4JxLXvr8ZCr0av OpKGFRdCOjDRUG-xdIp3tUXq7fW7hZY87U1OzRO4lTpIedTqn8nf2O3Zl4-YjlMAPXH8v5imRzsCMh4277a0cpvV2Yl2M1J9tzg3eDXZhxd8R P6djdyFzgctvP5KRjALmlOdEkfccvgEwMIHHTSdH970Am3zSAI 84yuDAAQCdH2x_m_k20SuDC-9ayMmQvJoU1KNKvhc_YgqNzOQ4pSvn3eNgy1eWaxDsvsaCv3ZK SP0G-py3SeLEsF2CX7fzoKFKrpc=w1634-h919-no
https://lh3.googleusercontent.com/cS45HVYkPExIyXkX7AfRknzXrmgzw0nLs5GTHs72Xr5MUE7p1U ePJP3zKyrHVuFBNW66Ozzz3LV5HcFQhfXhUdCb3NSv0XGKfsdB ujNXC-ISKRA-yl_T_ATIJEcKObmSRPPaBvukW5a4Gcrp5en6ccqWD-TbgsJxodcq4MQgs_KKT80DAncELVtb71YLXppnh-nrN3sCrx3cn0NWFtqtgoTyykhjGm2tEzpJY0SPCdnyEuSG2xup GeW4DWlkqShohcOBeUFjTrdb8diD4KDA-wbhT9ONtKDKdFk1UbXvzy1SRaYeHRkzAETEDEJhKCWjuPjVlLi yFa2RMSi8K2m327qQmjtTuIyFSUqmiDjnKe2vCPgNjRX3Jlev0 Dhy4LppgX770FnUHVNEcBWLdyW7IIiNdaqrHe17d2Ult41AS05 Z7ihhe6ka1kINBP4RGyaqL4Yzw5d1xrjI8EgEv71k87dK8UoFU DwKM7kpD8_YyWPzKscoTeAdRTROr_09wKQhOkM9txt-rhoQDm4RfGjVi02SWZ4iep7duvanrYotIlQx2_TN1lI27g-yNHNrsAnHyykX5YGwimM5t9BHgibxDmuMabyzz6B1Tlx_3SWWT QodMJqgryY_UUu8SzxM3pJ8VIH_D1DZJhrVbo1tvN6nfjo6cHg wciEgAygzmhTSoPs=w1634-h919-no

[ray1970]

You'll need to be Spider-Man to walk on those roofs. Looks slicker than owl poop on a wet rock.

[Irving]

Yeah those were installed on a 10/12, so you'd need some sort of safety restraint. I didn't even try to walk on them though, no idea if those are even load bearing at all.

[gnihcraes]

interesting setup. thanks for the photos of them.

[Grant H.]

I'd seen the press release on them, but I haven't followed up on how they solved the thermal efficiency problem.

Solar panels get less efficient when they get hot. If they don't have air flow behind them, why they are usually mounted on an open air rack, they produce less energy.

It's cool to see them installed though, Thanks!

[Irving]

I guess there were more than one in that neighborhood.

I also took a photo of the dumbest solar panel install I've seen (allegedly Solar City) but it's not on my phone anymore. :(

[Irving]

I only had a few minutes to mount this panel today, and once I started, something came up and I had to cut it short. I'll have to relocate the front driver side bolt so I can straighten that rail back out, but I'll have to do that later.
After eyeballing what I had to work with, I realized that if I cut out the bottom of the L bracket on each side, I won't have to cover any of the panel. It's already going to be below optimal as it is, so I thought I'd remove as much material as I could to give it the best exposure to the sun. I knew I was going to loose all the rigidity of the rack when I cut it, but since it only really provides lateral support for an occasional ladder, it's not that important. Adding the panel strengthens everything up, and if I really need to I can just bolt another bracket on the outside to regain that rigidity. I fully realize that this is another Irving Hackjob, but it's mostly experimental anyway, and no one will ever see it. In case you haven't realized it yet, the panel is mounted under so that I can still hold a ladder on that side. Most of the time it will be as pictured though. If it works out well and I do a decent install with the rest, I'll probably post up a write up. My next challenge is to figure out the best way to get the power wires into the cabin in the least stupid way possible.

Panel is an AcoPower 50W I got off Amazon. I don't know if it's any good or not, but it's the one I bought.
https://www.amazon.com/ACOPOWER-Black-Solar-Battery-Charging/dp/B01G53TUCE/ref=sr_1_3?s=lawn-garden&ie=UTF8&qid=1495425513&sr=1-3&keywords=Acopower+50w

https://lh3.googleusercontent.com/p4nt9dCiFor7Sw7YPl4Uq_uBrlvgn-JZ7u9Ho6pYkHWWS6lg0QS2PaTq-MkOpUW1GrlvfIh7OLJs26dapgl09_VOrdwkCtK6lN7CT8GyOyc TcDRxNVK5DgJ8E_9_1mGxbZ_csiaq0lLRe09HFJ9ta7q_b1m95 9YJQpO1aJ0VMYY2lF3NiQzjlqrbfH8LTCh10f5h9gAuGAlUJew nhVfEiIqFZtPrwIFI5cvn6wuJg4JRlHFhsiG_KRbDOyQRvtR15 dUk6WU7LEdoyTIhr-IYu4CUYfCLzdaQbe7TTyAmtS2TYv3Iq3L0y0mt44xS3Hol7Rnm LxEJ-eD1Pljz-cJOGq_TPDEoo6dErb3r013h9bRDmsE4Kzj87OoR8Lj78Y2k_Va KBOs8Ct2mdgZZIwiDZJrMubl4EvxVZwn7FEbuYmLVQ5XKR4BWs OhLH2s85D3u6BHEzBljfqMhnp0PnSqHLwehIZmbGBoWVQpsuqV Jp_w57W-hEczILaKNLqNd7cObpLtPzWrDoFoMclmxHuK98s8SOPYLIQLl1 g_nL8JtDyzDOpMb9n9sgbu0tMAxqLas9Wq3SB_HuYDUt7tSKSx QQmbfRTKgE4wYjx0wJp2LOfaESbV2j6AbDIzeHof_HrkYzma1l QUb85n2myB7h24Akxl_cK_GrJHj1vophzRy8yw=w1634-h919-no
https://lh3.googleusercontent.com/tdPuCP0mCFgVvBcn6E9jtaxOlW4uSDUOqSF2jLRmhFN3Mg_Y8-j_AGV0sODW015EilihX_hcE2btlYDo1Pm8UcP8i9YOU53pZ4Di dFIvSrJKOUmELIbnUKQ4hVVl17ys_faUzjlJq_iplxNEhuTDFx v9XswO37u76pArYV7RW3IjaVemddZ2FMl9w6laBv4_kWrQEN_9 9jQmDjWo8OHUNS7PdEwGzCKErDWaKkWY8CbJQoMUNG44CiO66j IFvq123eRbakBPSROnK5zqRwfkzfSwJn74UO8HVav-efj3sHIA-kUOTfZUlchjJ5Z2ru_1SmWgGFEktR9bROusGD8mYi943F07IFo dhSm7rI3_wQ1EWNDawcdBgr2b_lVOQLfx47oycgvujFgeLYmq6 wJRnp7aN3Q-NPLaEbpEPvVQbGFIlo10QNpr7pQ4VtGcHhXZORUlnfcJHMbl-mHg-bJcdpK-wdOHgxnVqzltcVto7Keb6wJKyo83JPsWyHY-ojK_YUB_3evMmjXu64tBrP-yzr1lPlbj5toVuwnI3VDe7ILYYtBvztXSu5XgNY-NUKaC_3buulydjZ8SN70Ntatzv5heVMWFKmzlZcHFD_kqoqZl_ AxDCGL4gtIgrgYlMmTedbFNYe6_lTjanLMc8VBRmblPOrPBznM o3L2ZQ0iE8dM=w1045-h588-no

[Great-Kazoo]

You want to mount that a little better, i have a few feet of unistrut you can have.

[Irving]

Once I redrill the one hole I need, it will straighten out that kink. Everything is fasten down with Nylocks, and the rack has been on the van for maybe 30,000 miles now (with no loose nuts when I checked the other day), so it should be fine until I have the time to straighten it out (hopefully tomorrow night). Thank you though.

[Irving]

Best solar install ever? Keep up the great work Solar City.

https://lh3.googleusercontent.com/gDbTLR_Gp2dy9MTf0VbmQ0rpf4UsJw0cf1brKxfn7GoGbshVvs LkiXWVHmFcGyDsI630m5d67oEIgTtLKkAZB8P4uapnh9HLMZv3 mAr_bNrXcCGtPDeI31Al9rw2CmBSobj7XU_fhEnoEbZFeaqovU vTur8jW0v2s4uENhbSODGFwGqv3eMMhlwtgS_7HN4DplnvMSJy YWAbtMGcJ9Qo5Wgb7DBYIMLRPOp1nmfTjSEzWU_qVWXjStk7_d BCn_KpNqeEj1IYa6uYbiXgUFkvRlBBdOQTwBGMYGfv-O4pcY0MsxwaSO1bPhT_BStVqIKlWVg4XPTaiumuC1dcS4DUqXh miaaeB2vFfiqOcB2thHS8527-NmzD0ywScC9OG-2mNxqZnBmnxn3pY9YS2HOnHKR3sJIWZmLJNkJxGBeUAJ3irgX2 ReYb67VO0Qr2UcFK9vePLUaoWR6NNzmSY-lbzhDdjBTqM_wA1iC-xZAFK0aLYLwJiGeNVb7UphG-H3eexuSbV0KzEKD8ex6aqSbAe7sQssGArc_sSNe72g1cHkjSOv D6orlysYx2kWhYg_vcdxy6-Ompgya2rS9LjkaTZkjlO-mv2U0_DxLk3IWEKjJVHNAxeKeNKFu42hsYitKZ-SR4UW0xHi6-e0xpiqJOwf0m-EkKGdRKjKofOvW8U9s=w1634-h919-no

[gnihcraes]

Update on my solar city situation. I was under the belief that when and if my roof needed a replacement, they Solar City, would come remove the panels for the roofing work. Then put them back on.

I've inquired and they send a cost estimate to me of $1,638.17. Uh, wait a second...

I guess I can hope that state farm picks up this cost. shit. Got to go look at my contract...

[gnihcraes]

4. SYSTEM REPAIR, RELOCATION OR REMOVAL

(a) You agree that if (i) the System needs any repairs that are not the responsibility of SolarCity under this Limited
Warranty, (ii) the system needs to be removed and reinstalled to facilitate remodeling of your Home or (iii) the
system is being relocated to another home you own pursuant to the Power Purchase Agreement, you will have
SolarCity, or another similarly qualified service provider, at your expense, perform such repairs, removal and
reinstallation, or relocation on a time and materials basis.

[Irving]

State Farm should pick up the tab. Let the adjuster know that Solar City won't be picking it up. State Farm will probably make you pay for it out of pocket first though.

[Irving]

This is what hail damaged solar panels look like; some pretty serious spangle going on there. Sorry the pictures aren't better, I was on a boom lift and the guy using it was just learning. Better than any amusement park ride I've ever been on, that's for sure.

https://lh3.googleusercontent.com/eIO-zJJP96A6wco6WCvmzWWm7c_ryItjjwBxt1umkJ4HveQpdqkv--AIBX080SN6sNH-hc9W0PwmMBwbwVSZgXarNqSLlzvUi6abqVePZCAN9B33EK2ppI 1p2H_tlbAmUkS3Z8vfi8tb8KvDLOvCmsIfDp1UNr6Xmbi588Gc Ghe4tmBfMXGXej2pU-5wDOmM0lxMQladgjf7DAB0BG8oj8O9iJoHTybetevKURhjD8p8 GSAr8WbOrYuY3ujFKD8CxKeUjpYnaJwC9Tn3OtHZBses2iCTRf XCJEwycepG3PwoDylRaJj4jtMAnlu0HF6fq91WIksqLSaRrMzO 3oVX5VEV5R7-mYRO6vRPG0Cq43c5KEzMVpPv1xq7OpSdwl-9n7bpL00tPEuMoWtIiRXkyPQfPU-M9w8qRyXcrdCS-8c2FXfKcJIPjzRsXFiseTLqXcZ--J9vj8aOypMi9E-528xadw-uD3UhXmuevOz7Z6WfwzDhTUJJHV5573QwuTZgHh2nFLwyzW7_2 ddoz8657tvPMwTj8BjtHsOEJcM8q0KredSji61__b9KF3PIvW5 CTdfUQrWfpMOzQKLWfWcfaJcsITmk8dp0t37T0m5ZdxIFhDWPA NAhInSpEKNZjUt7J2ZNqGMOw3hNzFrahOPHmPBlejQXLPkvgZT HjFtWCnQ=w1634-h919-no
https://lh3.googleusercontent.com/D9XsNhdiW5hS5HXEgAa-nqlY1tcdAyeB5alJ_pAbpX68f6WhhTqbzR6_gTvoZlJMbJtaMk cMtcjF1bLg8g5a3tWwSKe9-3QojxYiU_P4cMDF4MVQdUgQxVVKNBNq3xDi4c0tGEENduM7MLS 0PUT0Qui83IgyR9nhHDK0ZYMcFe822_rYxYyrQHFxnFPL_qZP3 VdIi7j8r4ymkc5C71f1HbLVO1jdow3IzF-FPYyH6Dppp8QvP3LlLheTcdDd33VHdcsjXV69QxSXN-x2WGwbEAi0wmYdJ0gl6JSmSp-VNFouqpfzS4MA2-vt1vvao75fa9nreM-3pG30eW0taxezPwWvFLC7F8VuFwxU_mCge3lqFo8EJGFrkbyjh 7wsFgNAEN7zYbpsBB8WxWIEcEr-H5BRXcgraZOyMw3ljLRoVr0PFd-f0OomLfpTou7kF9nQxGTX7K2qKkz4IW7bZXFOx_ZS5iVm6hjuB 3vR0vHsgB0u7y-ilfOyM-1a5ZX2KBD1o6L1iK1AVA4rnlQXjzCiqK3h3HfEtcnfwThniZ01 2k8je35c8jiGr0NQmEGcZyzjCJRzqD2jvE4it3fNS5K34tltyJ G7fE64pFCQJGnSQZk4yWz8lS0GowXIHcMCKFIsjEO5OR1BDUkS IRF3FUcO9j6M3Zm-NxoOMfa44-fbFFs=w1634-h919-no

[Irving]

Now that I had the time to look at that picture better, that is A LOT of solar panels. If my count is correct, I'm getting 49 panels. I want to say that is all one house. I wonder how much power that set-up generates.

[gnihcraes]

Now that I had the time to look at that picture better, that is A LOT of solar panels. If my count is correct, I'm getting 49 panels. I want to say that is all one house. I wonder how much power that set-up generates.


rough estimate 12,250 watts. (DC) assuming a 250 watt panel.

[Irving]

That's a lot more than most, isn't it? Aren't a lot like 4kW?

[Grant H.]

Now that I had the time to look at that picture better, that is A LOT of solar panels. If my count is correct, I'm getting 49 panels. I want to say that is all one house. I wonder how much power that set-up generates.

More than that. There are some on the face of the roof aimed away from you. Above the air conditioner.

Panels are roughly 30"x66", so gnihcraes is probably accurate in the 200-250W panels. 10.6-13.25KW based off that. I'd actually guess that that is an off-grid solution having that many panels. No guarantee, but that's a LOT of panels.

[Irving]

I see the other panels you're taking about now, behind the BreezeAir (been seeing a lot of those lately as well). This was an HOA community where most of the buildings are joined condos. Pictured is the single family home section. A lot of these newer communities that I'm seeing have a very heavy solar presence. I'm interested to know what percentage of people with panels have any sort of battery bank at all. I imagine the number is in the single digits.

[Grant H.]

I see the other panels you're taking about now, behind the BreezeAir (been seeing a lot of those lately as well). This was an HOA community where most of the buildings are joined condos. Pictured is the single family home section. A lot of these newer communities that I'm seeing have a very heavy solar presence. I'm interested to know what percentage of people with panels have any sort of battery bank at all. I imagine the number is in the single digits.

Agreed. The percentage that have any battery bank probably starts with 0. IE 0.1-0.9%.

The leased/purchased solar plan is almost entirely about generation and sale, not energy independence.

[Irving]

Here is an article about a solar neighborhood in Arvada.

https://www.csindy.com/coloradosprings/colorados-first-geosolar-development-in-arvada-is-a-model-for-any-city/Content?oid=10942887

[Irving]

Grant, would it be feasible to use a solar set-up with both capacitors and a battery bank? I'm thinking that the capacitors would be your workhorse for most use, which would keep your battery bank unused for longer periods. Seems like you could work off of a smaller battery bank for recovery if the super caps can be operating more quickly, giving the batteries more time to charge back up if there were several days without good sun.

I have an idea for a project. If it becomes a reality, I plan on contacting you as I'd like to make a serious effort if the time and money are there at the same time.

[Grant H.]

Grant, would it be feasible to use a solar set-up with both capacitors and a battery bank? I'm thinking that the capacitors would be your workhorse for most use, which would keep your battery bank unused for longer periods. Seems like you could work off of a smaller battery bank for recovery if the super caps can be operating more quickly, giving the batteries more time to charge back up if there were several days without good sun.

I have an idea for a project. If it becomes a reality, I plan on contacting you as I'd like to make a serious effort if the time and money are there at the same time.

Yeah, it's feasible. I have a couple ideas that have bounced around my head before that would make this doable. It all comes down to how you set it up on whether the caps get pulled down first or if the batteries do.

I'm curious what your idea is...

[Irving]

Well, I just built a chicken coop that has a South-ish facing roof slope that is 6'x10'. I'd like to load it with as many panels as possible. I could probably get away with like a 30w panel for all my chicken coop needs (auto opening doors and some winter LED lighting, maybe some cameras). I figure that if done well, I can have it double as a solar generator that I can plug my fridges or stuff into if I ever needed. I like the idea because it allows me to have something that is dual purpose and doesn't poke holes in my roof.

EDIT: I assume that it could get pretty complicated as far as running super caps and batteries since you'd still need a solar controller for the batteries, but maybe then you're reducing efficiency with the super caps. In my minds eye, I'd end up with a 500-600 watt solar generator that runs my coop all the time, but then I can run some speakers, charge tools, an electric scooter, or if the super caps work out, maybe even a saw or something when I'm building something outside. I just don't know how feasible it all is. I'm sure it can be done, but would it be worth it if it costs me $5,000? Maybe not. As with most of my projects, it seems like something I'd like to experiment with just to do so. Plus I'll have plenty of capacity if I wanted to add on with yard lights, or a pond/fountain with the pump and heater run off of solar or whatever stuff I imagine up in the future.

[Grant H.]

Well, I just built a chicken coop that has a South-ish facing roof slope that is 6'x10'. I'd like to load it with as many panels as possible. I could probably get away with like a 30w panel for all my chicken coop needs (auto opening doors and some winter LED lighting, maybe some cameras). I figure that if done well, I can have it double as a solar generator that I can plug my fridges or stuff into if I ever needed. I like the idea because it allows me to have something that is dual purpose and doesn't poke holes in my roof.

EDIT: I assume that it could get pretty complicated as far as running super caps and batteries since you'd still need a solar controller for the batteries, but maybe then you're reducing efficiency with the super caps. In my minds eye, I'd end up with a 500-600 watt solar generator that runs my coop all the time, but then I can run some speakers, charge tools, an electric scooter, or if the super caps work out, maybe even a saw or something when I'm building something outside. I just don't know how feasible it all is. I'm sure it can be done, but would it be worth it if it costs me $5,000? Maybe not. As with most of my projects, it seems like something I'd like to experiment with just to do so. Plus I'll have plenty of capacity if I wanted to add on with yard lights, or a pond/fountain with the pump and heater run off of solar or whatever stuff I imagine up in the future.

Your idea seems perfectly reasonable, but you are right, that it does add complexity since the batteries require a controller, and the super caps don't.

http://www.ecodirect.com/Canadian-Solar-CS6K-300MS-300-Watt-Mono-PERC-p/canadian-solar-cs6k-300ms-t4.htm

Gets you 900W on your roof space.

I'll try and draw some stuff up tonight as a starting point for you.

[Irving]

Thanks for the link, I was hoping you'd have insight into stuff that is better than I've been finding on Amazon. Seems like I might be able to build a pretty decent generator with 900 watts.

[Grant H.]

Thanks for the link, I was hoping you'd have insight into stuff that is better than I've been finding on Amazon. Seems like I might be able to build a pretty decent generator with 900 watts.

Sorry, got tied up welding last night.

Ecodirect isn't the best pricing that can be had, but they are usually a pretty easy place to look and see what's available.

These guys website blows, but they have good pricing. Call them to find out what they have and what the pricing is. They have a warehouse in Denver as well.
http://sunelec.com/home/

[Irving]

Thanks for posting that website again. I was trying to click on that link in the earlier part of the thread and it would never come up.

[Grant H.]

I'm working up an estimate for a massive DIY solar grid-tie - understanding of course that the permitting process is a pain in the ass times twelve.

http://sunelec.com/Solar%20Systems.pdf

Using that as a source of estimation, two 7.6KW Inverters and 60 280W panels (basically 2/3 of the 25KW system), plus the pro rata share of the racking, optimizer, and quick-mounts comes to about $20,000-ish. Estimating a budget of 2000 for conduit, copper, and subpanels, plus a budget of 2000 for permitting/planning, does that sound about right? 24K-ish for a 16KWH DIY install? This is for a sort-of-high end duplex with optimal real estate for panels [no trees, perfect south facing 1:3 roof]. Would there be ways to save additional money?

Now, here's another factor, I'd prefer not to separate the 7.6KW Inverters as one per side - I'd rather combine them on the main and then essentially feed each side as a subpanel. Perhaps asking Xcel to reduce the system to a single meter (if they would let us...?) As the electrical usage of each side is *not* balanced, one side needs to "borrow" power from the other.

So... what am I f'ing up in my figuring here. Because it's going to be something. [ROFL1]

I'm very comfortable roofing and working with power, but I have yet to dig heavy into engineering any kind of solar system.


Side question: I've heard in the past that it's better to use a ton of microinverters so that down the road, bad panels in the array don't feck the overall generation. What's your general thoughts on that?

I apologize. I didn't realize I had missed your questions. (The system you linked doesn't show right now, so I can't speak directly to that one).

I'm not as helpful on the grid-tie side of what Xcel can/will do, because I have generally stayed away from it. Most of the inverters are considered "load balancing", but it's the wrong direction. You want to load balance between two solar arrays, not between the solar array and the grid. That makes this a little more difficult.

I honestly don't think you are missing much in your estimate, at the $24k for the system. Ways to save some money, albeit likely take more time, is to build your own mounting solution instead of using pre-manufactured solar panel racks. You can also look at pricing things separately (sometimes the kits are a good deal, and sometimes they aren't). A quick glance says your 16.8KW of panels should be about $8400, Probably $9000 by the time they are shipped. You can then bounce around for different inverters and maybe cut some money out.

Did the kit you linked include any batteries? Are you wanting to run any batteries?

[Grant H.]

Side question: I've heard in the past that it's better to use a ton of microinverters so that down the road, bad panels in the array don't feck the overall generation. What's your general thoughts on that?

The microinverter game has both ups and downs.

While it's true that they help with a single panel failing, and not causing issues for the whole array, you also now have that many inverters that can fail. Generally, due to the pricing game that everything comes down to, the microinverters are not as robust and reliable as good quality Outback, Schneider, etc inverters.

It also means that you have 120 or 240 VAC (depending on the panel and inverters) running all over your roof. As a counter point, most MPPT solar arrays are going to be running up to 150VDC.

[JackRyan]

Any one know what size solar panel I would need to charge a single battery for my pop up camper?

[gnihcraes]

How quick do you want to charge it?

I use a 100 watt panel on mine. Full 8 hours to recharge on a sunny day and little battery use during that time. Battery isnt fully drained either before charging up. Sometime I'll add more panels for a quicker charge.

Sent from my SM-G960U using Tapatalk

[Grant H.]

Any one know what size solar panel I would need to charge a single battery for my pop up camper?

What size battery? Voltage and Amp Hours?

As gnihcraes asked, how fast do you want it to charge? FYI, a panel laid flat on the roof of a camper will not provide it's full rated output, so charging will take longer than expected based on panel rating.

[JackRyan]

I'll have to look. Might go with a golf cart style battery. Im not sure what came with the camper. I know the light are powered by it, but not funtional. So might as well up grade.
Are you saying you will get better power from a panel if its on a stand as to being flat?

[JackRyan]

Sealed AGM Gel Golf Cart Battery 12 Volt 35 Amp Hour

[JackRyan]

What size battery? Voltage and Amp Hours?

As gnihcraes asked, how fast do you want it to charge? FYI, a panel laid flat on the roof of a camper will not provide it's full rated output, so charging will take longer than expected based on panel rating.

Sealed AGM Gel Golf Cart Battery 12 Volt 35 Amp Hour

[Irving]

35 Amp Hour is pretty small, I feel like a 100W panel would be plenty for that. Remember, you can only charge a battery so fast, so having 10 x 100W panels wouldn't work as well as one might think.

[JackRyan]

35 Amp Hour is pretty small, I feel like a 100W panel would be plenty for that. Remember, you can only charge a battery so fast, so having 10 x 100W panels wouldn't work as well as one might think.

That would have enough power for the night? couple lights, might add small tv and dvd player, watch a movie, charge phones and tablets.

[Irving]

I don't know about adding a TV and a dvd player. For LED lights and charging phones and tablets, I'd say you'd be alright. Especially if you charge the phones during the day. I'd just watch the movies on the phones/tablets.

[JackRyan]

I don't know about adding a TV and a dvd player. For LED lights and charging phones and tablets, I'd say you'd be alright. Especially if you charge the phones during the day. I'd just watch the movies on the phones/tablets.

True....i might go 2 100 w panels and 2 deep cycle batteries. Expandable to 3 panels maybe over kill. Forgot to mention CPAP machine is a must. Go though on tablet regarding movies. thats what we did last trip with power banks for all.

[Grant H.]

I'll have to look. Might go with a golf cart style battery. Im not sure what came with the camper. I know the light are powered by it, but not funtional. So might as well up grade.
Are you saying you will get better power from a panel if its on a stand as to being flat?

A solar panel is most efficient when it is aimed directly at the sun.

In the random google image I have linked, you would want the panel aimed along the dotted yellow line.
https://www.pveducation.org/sites/default/files/PVCDROM/Properties-of-Sunlight/Images/ELEVATE.gif

The Elevation Angle of the sun changes daily, so you without an active tracker you won't get optimum sun all the time.

A good rule of thumb is to point your panel towards the equator at an angle equal to your latitude. 40? for the front range near Boulder. This is sort of a "happy medium" for a fixed installation between the high summer elevation, and low winter elevation.

So, to figure out how much loss you will have from laying it flat, there are two things to consider.
1. The difference in production at "Peak Sun" between a panel properly aimed at the sun and a panel installed flat will be ~15%. Your 100w panel is now only an 85w panel.
2. The duration of "Peak Sun" is significantly less with a flat panel, especially during the winter months with low elevation angles.

As for batteries, you need an idea of how many watts your lights draw, how long you want to be able to use them without damaging your batteries, and how fast you want them to recharge.

Golf Cart batteries are excellent options as they are built for frequent charge/discharge cycles, and to handle heavy current loads. This means they have thicker and heavier lead plates in them, which makes them last longer. Normal truck/car batteries actually kind of suck, as they are designed for very short but huge current draws (starting) and then they sit.


Sealed AGM Gel Golf Cart Battery 12 Volt 35 Amp Hour

That's not a very large battery, so if you have room to go larger, I would. Depending on where your battery lives, I would stick with the Sealed batteries, but it's not a problem as long as you understand that a flooded/serviceable battery will release hydrogen gas when charging.

With standard AGM, Lead Acid, etc batteries, you only want to use from 100% to 50% of the capacity, or else you will damage the battery and reduce it's capacity and longevity. Li-Ion is better, but requires more expensive charge controllers.

So, If we take your 35AH battery, and plan to only use 17AH out of it before recharging, you only need to replace 17AH before using the lights again.

In CO the "worst case" scenario for solar is a max of 4 hours of "good" sun per day (obviously much more in the Summer).
A 100w 12VDC panel will provide ~8AH for every hour of "good" sun it gets. This means, in 4 hours, you are going to get 32AH of production.

The advantage to a good quality solar controller is, they won't over charge (also bad for batteries) your batteries. They will let the batteries float when they reach max capacity, and essentially waste the solar panel production beyond that point.

So, you can go as small as a 60w panel to recharge your 35AH battery from 50% with 4 hours of sun.

I personally would go with a 100w panel, unless you are going to go larger on your batteries, and then you need to re-address your panel size.

[Grant H.]

That would have enough power for the night? couple lights, might add small tv and dvd player, watch a movie, charge phones and tablets.

This is all subjective on the draw that these devices have.


I don't know about adding a TV and a dvd player. For LED lights and charging phones and tablets, I'd say you'd be alright. Especially if you charge the phones during the day. I'd just watch the movies on the phones/tablets.

TV's are power hungry pigs (relatively). I agree with Irving on using the tablets/phones for watching a movie while camping.

You also have to consider the losses incurred by running an inverter to create 120VAC to run your TV, DVD Player, Etc.

Charging phones and tablets during the day, when you are likely to have an excess of solar, is a great plan.


True....i might go 2 100 w panels and 2 deep cycle batteries. Expandable to 3 panels maybe over kill. Forgot to mention CPAP machine is a must. Go though on tablet regarding movies. thats what we did last trip with power banks for all.

The size of your system depends on the space and weight you are willing to put into it, and the power that you need to use.

Your CPAP Machine should have a current spec on it's power supply (look for input voltage and current ratings on it - something like 120-240VAC @ .5A (random numbers)). Figure out how much power that wants, add in charging 2-4 phones at ~3AH/ea, 2-4 tablets at ~6AH/ea and you can start to build a power budget, and then spec your batteries and your panels to support your wants.


Once you get all that started you also need to think about if you want to be able to go a day or two without any usable sun (camped in the shade of trees, cloudy rainy weather, etc), and then you get into scaling your batteries and solar for surviving multiple days and how long does it take to recover when you do get back to sun?

[Grant H.]

Quick side note -

The power specs listed on a power adapter (like your CPAP machine) will be the most that it will ever draw. It may not actually run at that level normally, but that is the worst it will be (aside from blowing up and letting the magic smoke out).