Solar on the shop

[slow]

That's a good Solar MicroInverter 101 video.

He makes it sound like you can plug the micro inverter right into your household power.

There are products that literally work like that. Single panel to a 15 amp plug that backfeeds your house. No idea if or how they have any UL or other certifications.

 

[dcg9381]

Where I am, I "physical disconnect" is required by the POC - one for the panels and one for the grid - physically accessible from outdoor and labelled.. Even if the system is equipped with an NEC compliant "rapid disconnect" system. I'd assume that microinverters would be required to have a physical disconnect also... At least where I am.

 

[EricVonHa]

There are products that literally work like that. Single panel to a 15 amp plug that backfeeds your house. No idea if or how they have any UL or other certifications.

Where I am, I "physical disconnect" is required by the POC - one for the panels and one for the grid - physically accessible from outdoor and labelled.. Even if the system is equipped with an NEC compliant "rapid disconnect" system. I'd assume that microinverters would be required to have a physical disconnect also... At least where I am.

If a person decides to plug solar arrays into their house power without calling the power company.. here's the what if:

How much feedback into your house power (and your power company) before you get a call/visit from the gestapo asking "just exactly what are you doing?"

I'm under the impression that solar feedback arrangements need to be reviewed by the power company. In other words, EricVonHa the super solar guy, just plugged in a huge solar array into his house-hold power and is feeding power back onto the grid net positive most of the time.

I suppose 1) the power company would not offer an credit

2) threaten to shut off your power for non-conformance and not paying the piper.

 

[Jackfre]

PG&E requires, as does the county building dept, documentation for the permit and then a licensed electrician to submit the utility connection. There is no substitute for the correct and safe handling of the interconnection.

 

[SGKent]

We had a leg drop last week and everything in the house went dim. I ran out and pulled the main breakers for fear the refridge or HVAC might try to come on in a low voltage situation. These are rare here in this area - maybe a transformer went out, or a car hit a pole. So I have to imagine what would have happened in that situation if I was trying to backfeed my whole neighborhood from a unit plugged into the wall. Worse, if a lineman thought the line was cut off but this idiot was backfeeding. Who knows, maybe the dim lights was a neighbor backfeeding all of us and the power was really out.

 

[dcg9381]

I suppose 1) the power company would not offer an credit

2) threaten to shut off your power for non-conformance and not paying the piper.

I guess you could do that, IE - just plug one in to back-feed an outlet. Around here, the meter for solar vs non-solar is different and as I understand it won't process a credit. Unless you did some damage, likely the PoCo would never know... And providing 15A in - you're probably using that power.

Not saying I'd do it, that it's a good idea, etc... But I "get it".

Around here, PoCo requires an inspection and an appropriate install, but surprisingly does not require the work be done by a qualified electrician...

 

[Jackfre]

Progress. I spent most of last week doing the Iron Ridge Rack installation. Very impressed with the IR hardware and I say that having put many hundreds of collectors on roofs back in the 70’s. Due to snow loads a support every two feet, so 84 penetrations in a perfectly good roof. I going to drag a hose and sprinkler up there to see how I did prior to setting the collectors.
I did this roof work by myself. It isn’t hard, but at 71 it about kicked my ***. Flexibility isn’t what it used to be. I think I can pull a crew together the first of next week to set the collectors then will schedule the electrician.
Oh, and it was followed up with the excellent Emerald Pool IPA by our local Three Forks Bakery & Brewery.

 

[larry4406]

Jackfre- I hate ladders but enjoy my beer! Hats off to you!

 

[dcg9381]

Wow.. Thats a lot of footers on those rails... Nice work. Especially at 711

 

[walrus]

Nice work. Still pursuing my project but still not convinced I want it on roof. Lots of leak chances there.

 

[83VillageRepair]

If a person decides to plug solar arrays into their house power without calling the power company.. here's the what if:

How much feedback into your house power (and your power company) before you get a call/visit from the gestapo asking "just exactly what are you doing?"

I'm under the impression that solar feedback arrangements need to be reviewed by the power company. In other words, EricVonHa the super solar guy, just plugged in a huge solar array into his house-hold power and is feeding power back onto the grid net positive most of the time.

I suppose 1) the power company would not offer an credit

2) threaten to shut off your power for non-conformance and not paying the piper.

If your power company has any kind of "smart" meter they will immediately see reverse flow of power back onto the grid. This is the same signature that theft of service gives so they might be accompanied by law enforcement when they visit. As long as your usage is always bigger than the solar output of course there would be no reverse flow onto the grid.

If you are not on a solar rate the meter on your house might be programmed for forward plus reverse which would mean that you pay no matter which direction power flows. It is always good to talk to the power company (no matter how frustrating it can be).

 

[yeldogt]

Glad it's worked out .... I can never get the numbers to work. Even my place in NJ with all the rebates.

I would love to get something on my studio --- but, the roof faces east.

 

[Jackfre]

Collectors are up. The ramp worked out really well. Put up the first 16 in 3 hrs and then it got hot so, the last 8 the next morning. Roof work is done. I watered the roof heavily for a leak check prior to mounting the panels. Electrician is coming up tomorrow. I had banked some good will labor hours with the crew so The only labor charges on the system will be the electrician. It is apparent that my new hobby will be cleaning these things. In the photo you can see the Sequoia overlooking the building. The amount of pollen coming of that, the walnuts and the hillside is pretty amazing.

 

[jmkporsche]

Collectors are up. The ramp worked out really well. Put up the first 16 in 3 hrs and then it got hot so, the last 8 the next morning. Roof work is done. I watered the roof heavily for a leak check prior to mounting the panels. Electrician is coming up tomorrow. I had banked some good will labor hours with the crew so The only labor charges on the system will be the electrician. It is apparent that my new hobby will be cleaning these things. In the photo you can see the Sequoia overlooking the building. The amount of pollen coming of that, the walnuts and the hillside is pretty amazing.

Looks great! I hope that solar gets to the point where it will make sense for us here in the Pacific Northwest. I’ve got a southern facing roof on the shop and would only have to trim one tree.

Good luck and I look forward to updates.


Sent from my iPhone using The Garage Journal mobile app

 

[Shop Specialties]

Collectors are up. The ramp worked out really well. Put up the first 16 in 3 hrs and then it got hot so, the last 8 the next morning. Roof work is done. I watered the roof heavily for a leak check prior to mounting the panels. Electrician is coming up tomorrow. I had banked some good will labor hours with the crew so The only labor charges on the system will be the electrician. It is apparent that my new hobby will be cleaning these things. In the photo you can see the Sequoia overlooking the building. The amount of pollen coming of that, the walnuts and the hillside is pretty amazing.

Looking good and cannot wait to hear what kind of results you get.

 

[WisJim]

It bugs me when people only think of "payback" when considering solar electric. When will your TV payback it's cost? We bought our first PV panels in 1981 to supplement our off-grid wind turbine. They still work and put out close to original rated power. We have since moved, taking those original panels with us and adding a lot more panels over the years. Mine have all been ground mounts or on a rack attached to a wall--haven't done any roof mounts for myself. I was a certified small wind and solar electric site assessor for a number of years and worked with many satisfied customers. Now solar is so cheap compared to even 10 years ago that a good site assessment is less important.

 

[Jackfre]

I fired up the system yesterday. Briefly, and then had to power down as I have no interconnect agreement yet. With a fairly indirect sun angle we were measuring 32.4 amps x 240v = 7776w. I have to get the final on the solar and generator prior to being able to get the interconnect agreement from PG&E. Still working on the internet connection as well. While I would like to have the following be an example of superior and thorough research it actually falls in the dumb luck dept, I had thought with the microinverters that I was limited to a grid tied system. It turn out that my MI’s coupled with the Enphase combiner panel and Envoy system has the software to drive batteries. Having the generator for the utility safety outages I do not plan on getting them, but will monitor the cost of propane and decide down the road. It is nice having the option.
A problem has come up however. We are at about 3000’ tucked against a forested slope that is putting down vast amounts of pollen. I washed the panels yesterday morning for the test and they cleaned right up. This am they were covered again. I can get up there and do it, but realistically at 71, regular trips up there will make my wife kill me if an eventual tumble doesn’t. Pollen and dust are the problems. It hasn’t rained in weeks. We are possibly looking for rain this week, but after that it more than likely won’t rain again until Oct/Nov. I’m thinking of a spray bar I could attach to the top rail across the 27’ array. Maybe I will make it crank up and down 15-20*. Add a pressure pump and It might just do the trick. Very early stages of thought on this so much obliged for ideas.

 

[walrus]

I fired up the system yesterday. Briefly, and then had to power down as I have no interconnect agreement yet. With a fairly indirect sun angle we were measuring 32.4 amps x 240v = 7776w. I have to get the final on the solar and generator prior to being able to get the interconnect agreement from PG&E. Still working on the internet connection as well. While I would like to have the following be an example of superior and thorough research it actually falls in the dumb luck dept, I had thought with the microinverters that I was limited to a grid tied system. It turn out that my MI’s coupled with the Enphase combiner panel and Envoy system has the software to drive batteries. Having the generator for the utility safety outages I do not plan on getting them, but will monitor the cost of propane and decide down the road. It is nice having the option.
A problem has come up however. We are at about 3000’ tucked against a forested slope that is putting down vast amounts of pollen. I washed the panels yesterday morning for the test and they cleaned right up. This am they were covered again. I can get up there and do it, but realistically at 71, regular trips up there will make my wife kill me if an eventual tumble doesn’t. Pollen and dust are the problems. It hasn’t rained in weeks. We are possibly looking for rain this week, but after that it more than likely won’t rain again until Oct/Nov. I’m thinking of a spray bar I could attach to the top rail across the 27’ array. Maybe I will make it crank up and down 15-20*. Add a pressure pump and It might just do the trick. Very early stages of thought on this so much obliged for ideas.

Interesting on the micro inverters, didn't realize they would charge batteries. Is the combiner on roof? Or do you bring down individual wires from each inverter to the combiner in shop? Any pics of the controls and wiring to the controls? I'm pretty sure all the wiring from solar panels to Micro inverters are plug and play, I'm interested in seeing stuff after the inverters.

 

[Jackfre]

The Enphase MI’s are supplied with their Q-cable. It came in a string of 24 and I cut it for banks of 8. You snap it into place and daisy chain across the array. To mount the mi’s for a bank of 8 and secure the wire To the Iron-ridge racking with supplied clips took about 15 min. I had a junction box flashed into the roof and brought the three banks to that box and into the attic. It is AC, so 3 romex circus to the combiner. The blank space in the combiner would handle the breaker for the battery circ, if I do it.

 

[walrus]

The Enphase MI’s are supplied with their Q-cable. It came in a string of 24 and I cut it for banks of 8. You snap it into place and daisy chain across the array. To mount the mi’s for a bank of 8 and secure the wire To the Iron-ridge racking with supplied clips took about 15 min. I had a junction box flashed into the roof and brought the three banks to that box and into the attic. It is AC, so 3 romex circus to the combiner. The blank space in the combiner would handle the breaker for the battery circ, if I do it.

So you are into combiner, then to disconnect and then into panel?
Wholesale solar is have a 10% off sale until Friday. Some deal on 60 cell 360 watt panels, 21% efficiency . 8600 watt system for 13,000 and change. Seems like a decent deal. I have to add for different racking for a ground mount.

 

[Jackfre]

Yes. I just looked at the Ironridge site. I really liked the way the rails handled on mine and the XR-1000 looks good. Their fasteners are high grade SS. I used to build the ground mounts with 2 & 3" Channel off the sono-tubes, 40+ yrs ago. Whatever your base is I suggest using the rails. When I bought my system I bought just the straight Enphase Envoy controller. When going over the system components with my electrician he mentioned the Combiner and said it just makes things easier. I returned the Envoy and bought the Combiner. By the time i sourced the box and other hardware for the straight Envoy I doubt the Combiner was much more than $100 bucks over. Spend some time on Enphase's site. They have many training videos. Oh, the Combiner has the Production CT (current transformer) built in. You have to run a pair of supplied CT's to your main to read your utility power consumption. I used the Sun Seeker app to map my place out. It works well. You can likely find the rack rails locally. My electrical supply yard had piles of them. One of the best things about the racks is the boxes they come in 14' long top and bottom makes a 28' hot wheels race track my grands, 4, 6 & 8 are having a ball with them. I bought on another WS deal before the end of Feb and was satisfied with the deal and they have been excellent in support.

 

[walrus]

You have to run a pair of supplied CT's to your main to read your utility power consumption..

My main is 200 ft away from where I plan to feed the solar. I want to feed into a 100 amp sub in my shop, its fed under ground to my house where meter is. Sounds like that might be an issue?

No solar stuff at supply houses in Maine, couple of large solar installers but I doubt they would sell to me except at over retail

I plan on putting 3" pipe in the ground, hopefully using a tractor to drill holes, few bags of Sakrete and away I go. The iron ridge racking video I watched was done like that. I need 40 degree tilt

 

[Jackfre]

In order for you to see what you are using/producing you need the CT's. As noted the production CT is in the Combiner. The way my place is wired I have the main feeding the house and we pulled 100 amps for the shop off that panel. In order to have consumption on both the house and the shop I needed 4 CT's. We pulled the ground off the shop panel and pulled it back to the main. Attached the wires an pulled them back. Easy...from 10'. Look into it.

 

[walrus]

In order for you to see what you are using/producing you need the CT's. As noted the production CT is in the Combiner. The way my place is wired I have the main feeding the house and we pulled 100 amps for the shop off that panel. In order to have consumption on both the house and the shop I needed 4 CT's. We pulled the ground off the shop panel and pulled it back to the main. Attached the wires an pulled them back. Easy...from 10'. Look into it.

My feeder to shop is teck cable, no pulling conductors in or out. Its like metallic liquid tite, the conductors are pulled in at the factory, roll it in the trench and back fill. I'm sure there is some way around it. I still have lots of research before pulling the trigger.

 

[dcg9381]

Glad it's worked out .... I can never get the numbers to work. Even my place in NJ with all the rebates.

Well, even for those of us that can self-install at about 50% of retail, the numbers still don't "work" for a long time...

NJ probably full of upcharges on the contractor side. Can you guys pump your own gas yet?

 

[earl84]

Curious on the ground mount. I’ve been doing some looking at installing my own system, and the IronRidge and Unirac both require crazy big holes, like 12” holes 7 feet deep, or 24” holes 6 feet deep. Seems excessive, is that what you guys are experiencing? AHJ says the wind load has to be 90 mph.
Where I live and how we use electricity and the 14 cent/kWh, our payoff will be 5-6 years.

 

[Jackfre]

Well, they do have you by the short hairs. You do want them to stay where you put them. If your structural says 12", 7' then that's it, unless the engineer get creative. Should be fun drilling those. Not for no reason do they call them the Rocky Mtns. I felt much the same way when they said an anchor every two feet, but mine pales in comparison to your work. How large is your array? Will it be a single plane or multiple rows at what angle. You might be able to get by with a couple large anchor points and bridge them with sufficient steel to carry the load and handle the deflection, but again that is up to the engineer who has to stamp the plans. Once that sub-structure is in you then can look at IR or the other racking to actually mount the collectors.

 

[earl84]

Thanks. I didn’t mean to hijack your thread, sorry.
But to answer your questions, I will have two rows of 8 panels, 35 degree tilt. Unirac requires two 24 inch holes, 6 feet deep. I’ve looked into the digging and have some experience with digging 12 inch holes 2-1/2 feet deep with the rented auger from HD. The smallest rock stopped it cold, so that’s not an option. Ended up practically digging the holes by hand anyway.
Rental skid steer with auger and extension will be almost $800. Played around with my super cheap HF electric pressure washer to drill holes and a shop across sucking out the mud, and I couldn’t believe how well it worked. Made a mess, but I had a 12 inch hole about 18 inches deep in about 5 minutes. Hydro excavation it is! I’m buying a trash pump and a nicer pressure washer and am going to go to town. At least, that’s the theory. I have lots of time right now, plus I love doing this stuff. And I’ll have a trash pump and pressure washer to keep for way less cash. Might come in handy if I end up building a shop next year.

 

[dcg9381]

Curious on the ground mount. I’ve been doing some looking at installing my own system, and the IronRidge and Unirac both require crazy big holes, like 12” holes 7 feet deep, or 24” holes 6 feet deep. Seems excessive, is that what you guys are experiencing? AHJ says the wind load has to be 90 mph.
Where I live and how we use electricity and the 14 cent/kWh, our payoff will be 5-6 years.

Those kind of depths are nuts. They may be correct for wind loads - but sound really high to me. Generally, the rack mounts specify how much support ("L") brackets they need per feet of rail. Maybe they consider "worst case" soil. I've done two of these systems, maybe 18 panels, 35 degrees tilt, I've done them with about 8 posts holes anywhere from 2-2.5' deep, but our ground is very hard (requires a jackhammer). To dig a 7' hole here, you'd need a rock auger and I there is darn near nothing that would pull 7' of concrete out of the ground. Our footers on foundations (engineered) are not that deep...

I'd alternately propose that you're laying these on concrete footers (rails) - or a concrete foundation...

 

[dcg9381]

I know that areas outside of the us that are approaching solar "saturation" - which is something like near 30%.

Wikipedia says this about Oregon:
"Under the approved rules, residents and businesses who install solar systems can enter a 15-year contract with investor-owned utilities in the state where they will receive guaranteed monthly payments over the life of the contract with rates ranging from $0.55 to $0.65 per kWh.[13] Funding will come from an estimated one half of 1% increase in electricity rates.[13] The trial program ends after four years and the entire project's size is limited to a maximum 25 MW.[12]"


That rate of pay back, if I have it right, is 500% more than what I pay for residential power... If that's right, no wonder so many people are installing these systems.

Until battery technology changes, there is a practical limit to how much solar can do for us as it can go completely "off" during high demand days (like cold high snow days).

Do figure out how your POC does utility credits and net metering. Mine credits dollar for dollar monthly until I over-produce and then buys at wholesale (while charging me $20 a month for the grid tie)..

 

[walrus]

I just got a plan for a ground mount. I think its a generic plan. 7 ft holes, 1 foot dia. 3" pipe 5 ft down. For my area its a 40 degree tilt. I live on the coast of Maine so I can get some winds but I'm sheltered from SE and NE which would be the worse. I priced 3" galv pipe today. I'd have 3500 bucks in pipe let alone a foundation. I'd probably switch to black iron, that would last longer than the panels will. Being in rural Maine I'll bet I can do whatever I want except break NEC. I saw one ground mount done with pressure treated Maybe use galv below grade and blk iron above?

Its obvious a roof mount which my shop was set up to do is much cheaper. All I'd have to do is cut some trees which I'll burn for heat anyway. I still think using solar and mini split heat pumps makes it worth doing.

 

[earl84]

I just got a plan for a ground mount. I think its a generic plan. 7 ft holes, 1 foot dia. 3" pipe 5 ft down. For my area its a 40 degree tilt. I live on the coast of Maine so I can get some winds but I'm sheltered from SE and NE which would be the worse. I priced 3" galv pipe today. I'd have 3500 bucks in pipe let alone a foundation. I'd probably switch to black iron, that would last longer than the panels will. Being in rural Maine I'll bet I can do whatever I want except break NEC. I saw one ground mount done with pressure treated Maybe use galv below grade and blk iron above?

Its obvious a roof mount which my shop was set up to do is much cheaper. All I'd have to do is cut some trees which I'll burn for heat anyway. I still think using solar and mini split heat pumps makes it worth doing.

This sounds like the Iron Ridge system. I talked with them and messed around on their website design tool, and that’s basically what it ended up with. I also spoke to a Unirac rep and he designed a system for me that was much less expensive but required larger holes, only two of them though. Maybe I should go rogue and do whatever I want since it only has to pass an electrical inspection, no structural. But I just don’t trust my own engineering, haha. My power company has a rebate up to $750, and they do net metering dollar for dollar until I overproduce, then reimburse at wholesale, and I pay $20 to be tied in to their grid.

 

[dcg9381]

To me, I build steel that will handle the weight of the panels. 20 panels is about 800 lbs, and 8 x 2-3/8" galv steel pipes can easily hold that vertical load. The rest is standard square tube and we use big self tappers for the feet of the panel mounts.. Because the mount systems distribute the load very evenly, it's not like you have to get complicated with the engineering. Yes, you probably have to worry about uplift forces, especially if wind is possible on the back side of the tilted array, but no way you have to dig down 7' per hole - at least not in this soil... Mine have been done on hillsides where you can't easily uplift the high side of the array... so might be different if you are putting them on a ridge.

 

[walrus]

This sounds like the Iron Ridge system. I talked with them and messed around on their website design tool, and that’s basically what it ended up with. I also spoke to a Unirac rep and he designed a system for me that was much less expensive but required larger holes, only two of them though. Maybe I should go rogue and do whatever I want since it only has to pass an electrical inspection, no structural. But I just don’t trust my own engineering, haha. My power company has a rebate up to $750, and they do net metering dollar for dollar until I overproduce, then reimburse at wholesale, and I pay $20 to be tied in to their grid.

It is iron ridge system. Wholesale Solar sent me another plan with 2" galv. 8 piers instead of 4, something like that anyway. I'll have to check 2" pipe prices. Not sure who I could get to drill 1ft holes. Soil is bony as all get out. I doubt drilling will work. I'm thinking trenches and then fill with concrete.

 

[472scout]

If you weld cross braces to the pipe to counter uplift maybe the engineer would sign off on shallower holes? Just a thought from a non-engineer. A lot of farmer/ranchers have auger tractor attachments if you know any.

 

[Jackfre]

"Soil is bony as all get out." If you are able to find a post hole auger make sure you have plenty of shear pins in your pocket. I helped a friend drill some fence holes up in Ellsworth years ago and we had a heck of a time. They do say that it was the "rocks of New England" that settled the west.

 

[dcg9381]

Soil is bony as all get out.

We deal with layers (feet) of limestone. The tool for the job is the rock auger. You can't punch a trench in limestone without using a rock hammer and then scraping it out with a bucket..

If your rock is harder than limestone, I'm not sure how they do it...

 

[walrus]

"Soil is bony as all get out." If you are able to find a post hole auger make sure you have plenty of shear pins in your pocket. I helped a friend drill some fence holes up in Ellsworth years ago and we had a heck of a time. They do say that it was the "rocks of New England" that settled the west.

I'm 20 miles west of Ellsworth, couple miles off Rte 1. I'm on top of a hill, I planted a small apple tree last weekend. I couldn't even get a spade in more than a few inches. I had a pail full of rocks once hole was done. Go to the bottom of hill and you won't find a rock, its all clay.
Its not limestone but small rocks(maybe big ones also) that are every where. The auger on a tractor will just bounce off. You would need an auger on a skid steer with down pressure and then the auger would go off track.

 

[PhantomEB]

I’d think if we ever move to the acreage we want, then yup I will do solar on the whole south facing Side of the roof of a 30x40 or 40x60....as well rain totes. No freakin way am I paying to keep my toys clean!

 

[reader2580]

I bought my solar ground mount from Malina Solar. Price was very reasonable for 16 60 cell panels and the cost goes down from there with more panels.

The advantage with Malina Solar is they use helical anchors instead of concrete. I paid $275 to have a guy with a large skid steer spin them into the ground. It had to be a large skid steer with a high reach because the anchors are pretty long. The operator only had to idle the engine to spin them in.

Malina Solar is in Ontario, Canada and is part of Cargowall Limited. I got a good deal in part because the USA distributor used to be here in Minneapolis. I was able to pick up every locally with no shipping. The bad part is Malina Solar/Cargowall seems to be closed due to COVID-19. I have been trying to reach them for weeks and they never returned my voicemail.