diy solar

diy solar

Introduction-Obsessed Noob

sethile

New Member
Joined
Dec 29, 2021
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113
Hello All,
New here and really happy to see all the great information! I've been watching a lot of Will's excellent videos, and sorting out some system plans.

In terms of experience. It's limited--I've installed a small 100W PVM system on my 1976 25' sailboat. Batteries are just 2x80AH Deep Cycle Flooded Lead Acid, but after all my obsessed watching of Will's videos I hope to upgrade that to DIY LifePO4 batteries soon. In the process of installing the solar I completely gutted and re-designed/installed the entire electrical system on the boat using marine grade wire, connectors, and components. Based on my initial inspection of the system before planning the solar it's a miracle the boat had not caught fire! I suppose older RVs are similar.

I'm about to install a 200W 12V MPPT system for my storage shed. My hope is to use it to charge yard tools, while providing energy for lights and and some USB and 12V auto type charging ports for back up. I've ordered a HQST 200W Poly 20A MPPT kit. Other components I ordered include an SOK 12V 100AH LifePO4, GoWISE 1500W Pure Sine Wave Inverters, Blue Sea Fuse Block, and a 200A ANL fuse. Excited to get started on it. May have some questions once I start...

Depending on how this little shed project goes, I'd really like to install a larger system on the house. I had been hoping to do a grid tied system, but It's starting to look more than a little ambitious based on the red tape involved, the low electrical rates here, aging roof shingles, and East/West roof orientation that includes some shade. Just not a lot of clear sunny real estate up there! Still researching and crunching numbers, but I'll likely opt for an off grid system to lower grid consumption and provide backup power for critical loads.

The Titan systems look great! I kind of like the idea of putting together a DIY system, but I'm starting to wonder if that makes sense given how well set up that appears to be. Are folks still happy with them? Any news on when they might be in stock again? Thoughts on DIY off grid, and/or some sort of hybrid systems would also be really interesting...

Happy New Year!
Scott
 
Welcome to the forum!

I suggest you start by using the search function on the forum for info on Titan. There are also tons of threads on DIY off grid/on grid/hybrid solutions on here - no one size fits all - but that should get you started.
 
You can get used solar panels really cheap, and in many cases they may have half their life ahead of them and produce nearly new wattage. If you can find an individual local, or have a local wholesaler, a 250watt panel, with manufacturer's label, can be had for ~$60.

The panels are only a $slice$ of the pie though ...
 
You can get used solar panels really cheap, and in many cases they may have half their life ahead of them and produce nearly new wattage. If you can find an individual local, or have a local wholesaler, a 250watt panel, with manufacturer's label, can be had for ~$60.

The panels are only a $slice$ of the pie though ...
I've been checking out used panels at SanTan solar. Pretty compelling! I don't know of any local opportunities for them, but that may very well exist... I haven't given up entirely on a grid tied system, which would require going with new panels from what I'm reading. And yes, it seems like the panels are a somewhat small slice of the pie, especially compared to batteries... And even if I can somehow pull off a viable grid tied system, I'm going want battery back up. Sitting here in Western Kentucky, about 20 miles east of Mayfield. We lost power for a few days, but nothing like the horrific situation they faced...
 
I'm an hour west of Mayfield and 45min North of Kennet. We barely missed the bad stuff.

AFAIK, new or used, if the panel has its manufacturer's label, it can be grid tied. SanTan sells a lot of white label/no label/snail trails. Snail trails may, or may not, come w/manu labels. They ship by the pallet and it is expensive. Best to order a pallet full.

Although batteries have come down in price, in my book, they are the $$$ in an off grid system. You could go the hybrid route; power when the sun shines even if the grid is down.

There is a solar dealer East of you that may be of help. A member here reported good dealings with https://middletennesseesolar.com/
 
I'm an hour west of Mayfield and 45min North of Kennet. We barely missed the bad stuff.
Wow! I had just seen this, and then had to go deal with the weather radio going off to usher in the New Year! Timely ;) Just a watch, though... Hopefully we both dodge the bullet again on this one...

Thanks for the tip on Middle TN solar! It would be great to be able to pick panels up locally... They're showing 6x275W panel pallets for $311!! Definitely going to check into that....

Happy New Year!
 
There is a few forms of Grid Connected.
1) the Most obvious is the one with Feed In Tariffs which allow you to sell back power to the grid.
2) the less obvious, Grid as Backup Power.
3) solar & grid combo

1) Is most problematic with permits, inspections and a lot of red tape & $$ to go with it.
2 & 3) no red tape or permits - You are NOT pushing ANY power to grid. BUT for Insurance Co, more than likely need inspection & certification.

I will not talk Grid Tied Feed-In, others can answer on that.
2&3 is a mix of Standalone Solar with Battery that is still connected to Grid Power but ONLY used to charge the batteries if/when they get low.
These use the solar panels to charge teh batteries and provide an AC Circuit Panel to drive independent circuits you do not want connected to grid, while another "Grid Panel" serrves the circuits you want on grid. This method can accomodate Load Shifting forbest TOU (Time if Use rates) usage or for Load Shifting.

Many AIO's (All In Ones) like those from MPP or Growatt can accomodate a GenSet AC Line In and a Grid Line In as a charge source. Other equipment (Higher grades) can also do this and they can be programmed for the method to operate with priorities... for example, A- Attempt to charge from Grid, if not avail fall back to Generator, OR the other way around if you wanted. There are many ways to acvcomplish things.
 
@Steve_S Concerning "2&3", from the literature received from our small electric coop, I am not so sure about this. If not feeding power into the grid, from what I can gather, our coop still has requirements on my solar system beyond no back-feeding the grid when the grid is down. Among other things, design/inspection by a certified EE and inspection by their own EE. Concerned enough to hold off my build until things can be clarified.

Some of the hybrid inverters can 'create their own grid' and power your home when the grid is down and the sun is up, without battery. Off the top of my head, mpp's pip and some Growatt models can do this. From utube vids, they work, but work better with a battery.

@$.19watt, that sounds like a great price for new panels. If they are close enough, make the drive and save a ton in shipping. FWIW, it cost me $380 to ship one pallet. You will probably want more than 6 panels so take a truck knowing the wieght is going to add up.

About the storms; yep, after all the devastation a few weeks ago, a slight chance of severe weather had me a bit uneasy.


... $.19 cents a watt sounds ridiculously low. That $311 price must be per panel.
 
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If all you are doing is pulling power from a 120V/20A plug in your house for the Inverter/Charger/AIO to charge batteries, then it is nothing more than a Battery Charger as far as the Power Co is concerned. If that Charger also uses solar panels on your roof is moot. That would be no different that them telling you, that you cannot use a Car Charger to recharge your cars 12V when it is dead... It does not and cannot push power to the grid. If a "Coop" or anyone Bullies about you using their grid for Charging a Battery, that one messed up place. What would they do if you just did not have a Grid Connection at all and went 100% Off-grid, disallow a Building Permit or add taxes & fees or ???

My own Samlex EVO-4024 has just this kind of functionality, 2 AC Inputs, 1) Genset & 2) Grid power for charging ONLY, with built-in programmable ATS and more.

Powering without Grid or Battery... Great Sales pitch ! How does that work on cloudy & stormy days ? And just how consistent is it ? Not everyone and every place is blessed with clear and cloudless days 365 days a year. Sorry to be a tad sarcastic but really...
 
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Valid point. Contacting the elec coop and digging deeper into the issue. I assume one of their beefs would be with the automatic transfer switch locking out any feedback to the grid, especially if the grid were down, and possibly the transfer switch being UL or whatever certification they require. Did you have to prove the ATS would not back-feed into the grid? Did they require any kind of certification?

Sarcasm noted. A good selling point indeed. Yes, they work much better with batteries, but in a pinch some electricity to keep a frig or well running just long enough to do what is needed ... my kingdom for a horse.
 
@Steve_S

This is my elec coop's reply about using power from the grid but never feeding to the grid, "If you will not be tied into the grid at all then you would not need a net-metering agreement but if you need power from us at any point I think the net-metering agreement would apply."

Apparently, they are considering anything connected to a PV panel more than a simple battery charger.
 
Thanks for all the helpful information to get started with this, folks!

I had a nice discussion with a tech at our local power company yesterday. He was very helpful, and very reasonable. Our meters are already capable of reading both directions. Cool! But then comes a deal breaker for grid tie--our local coop (Murray Electric) is fed by TVA (the Tennessee Valley Authority), which is not under our Kentucky Public Utilities Commission, and therefore not required to offer net metering like the rest of the companies in Kentucky!

TVA's reading of the law that established them in the first place disallows net metering! Sure seems like that needs to be sorted out at some point! Meanwhile you can apply for a $0.02 per kilowatt payment for what you manage to feed into the grid (we pay around $0.10 a KWH for power--at least it's cheap ;). So much for grid tie! I will connect to charge, and he said if I do anything other than just plug in a controller/charger/inverter through a wall outlet they'd like to do a feedback test, just to be sure. And he offered to give me contact information for the inspector they use if I want to run anything by them. Seems very reasonable. I've 1/2 way considered a critical load panel and would want to make sure I'm compliant with that, and they'd certainly want to test it for grid feedback if I do that, and hire an electrician friend to help. Having the inspector out to look over things might help with homeowner's insurance too, regardless.

Supposing I wanted to take TVA up on their not so generous 2 cents per kilowatt offer: first I'd need to apply, and if I qualify and tie in someone at the local utility has to keep track of it, and submit it to TVA. He said it takes a tech (usually him) about 45 minutes per solar customer. And, they have to charge their time against whatever TVA sends. Of the 3 solar customers he has tied to the grid he's only ever seen a check go out to a customer once (for $4 and change). There is one large installation, 30KW I think, that only feeds the grid and does nothing locally. It's at a local car dealership, and looks impressive! They cut their own deal with TVA and apparently managed to negotiate a much better deal. They also have a smaller installation (not grid tied) that supplies a portion of their own power.

I finished my little storage shed installation (200Watts, 20Amp MPPT, 1500 Pure Sine Wave inverter, 100AH 12V SOK LifePO4). It's working great! Wired up some 12V LEDs and charge ports, and will soon be charging yard tools off of the inverter. Had two nice sunny days to test it out. Now it's snowing, and cold! Even if it clears up and gets sunny it will be too cold to charge the battery until I can insolate and heat a box for it. So that's the next project. Suggestions? I'll search after this post...

Meanwhile I'm currently figuring out how many panels I can fit on my precious little unobstructed area for a house system. It looks like around 5K worth on a south facing brick wall to start with (going to need a roof in 5 to 10 years, and it's oriented East/West anyway). I'll plan some expansion potential into it in case things change (maybe after a fresh roof). I'll be sticking with UL listed devices and grid tieable panels (likely used, though), just in case something changes down the road. So far I like the idea of 48V system based around something like the MPP LV6548 6.5KW. One would likely do it, but it's nice they're expandable...

Thanks again for the help!
 
Excellent information concerning the coop. Did they mention requiring UL cert for any of the equipment? This part has me thinking " ... anything other than just plug in a controller/charger/inverter through a wall outlet they'd like to do a feedback test, just to be sure ...". So he's saying they have little issue with a solar charger/controller/inverter, but just in case? How do they know the difference between a solar controller that can or cannot feed the grid, or one that does/does not have an ATS built in? Did they mention any kind of lockout transfer switch, or any such equipment, to isolate your solar power from the grid? Crossing fingers our coop will be as cooperative. Please keep us posted with updates.

If we fed back to the grid, I was guessing ~$.03 to the grid, and like you, we pay around $.10 from the grid. IMO, feeding the grid isn't worth the hassle.

Although it may not sound like it, I do agree with Steve_s concerning batteries; they really are needed.
 
This part has me thinking " ... anything other than just plug in a controller/charger/inverter through a wall outlet they'd like to do a feedback test, just to be sure ...". So he's saying they have little issue with a solar charger/controller/inverter, but just in case? How do they know the difference between a solar controller that can or cannot feed the grid, or one that does/does not have an ATS built in?
In the case of an installation they have questions about, and I assume anything wired into the service (beyond a wall outlet), they do a test by shutting off your power and seeing what happens. Either verifies you don't need a switch, or if you have one, it's working correctly. He actually shut off power to a customer earlier in the week who had energized a grid tied system before having them out to test it . When they did test it, it failed (oops!)! He didn't seem all that upset about it, just that they'd keep him off grid until he can get it to pass. I certainly understand they need to do that. As soon as the power goes down here they have crews out working on what they presume is a dead grid, although I imagine they have some safety protocols to test things first. I'm guessing generators cause way more issues for them than solar--several generators on our block alone, although I don't think all that many of them are tied into panels...

He did not mention anything about UL listed equipment. From what he said, it sounded like you pass and you're good to go as far as they were concerned. Insurance may be an issue, though. When I figure out what I'm doing I'll run it by my agent. I have yet to check with the city regarding permits. They sure have requirements for remodeling! Anything involving electrical or plumbing, and some amount of square footage will also require a permit

We moved here from San Diego 26 years ago. I have to say, as much as I appreciate SoCals forward thinking on solar, they certainly don't make things easy for DIYers. It's refreshing to have down home folks here talk you through the situation with a drawl and a flexible attitude ;)

Although it may not sound like it, I do agree with Steve_s concerning batteries; they really are needed.

Oh yes, batteries for sure! Even if we were to grid tie... Our up time here is really good, but it's sure not 100%. and the storms that tend to take it down are more frequent, and more damaging....

Just ordered a heating pad and a temperature control module and will add those to an insolated box for the battery in the shed. This forum is great! Thanks folks!
 
... $.19 cents a watt sounds ridiculously low. That $311 price must be per panel.
Yes, sadly, I think you must be right... The wording made it look to me (a hopeful naïve noob) like the price was for the pallet of 6. No way that makes sense. Back to looking at SanTan, but it would sure be nice to find a source close enough to pick them up. I hate burning up money shipping large heavy things, but it's seldom cost effective to drive more than a couple of hours each way. Fuel for the vehicle, and for me adds up pretty quickly.
 
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