Electric Boxes for Solar Roof

by Ben N on May 28, 2017


I had to double-check and saw that it’s been over TWO WEEKS since my last solar garage update. I’ve just been busy, working out of town and on the weekends.

In the time that I’ve had, I’ve chipped away at getting the racking installed over the course of several evenings. After that, I also installed the micro-inverters and trunk cable.

Today, I got to take a look at what I plan to do for the electrical junction boxes on the roof. I have three sections of 240V trunk cable – one for each row of eight solar panels. Each of those cables needs to go into a junction box where it can connect to plain 12 ga wires and get routed through conduit down to the side of the building. From there, it will go into an AC Disconnect and then finally into the building to the main circuit breaker panel.

I purchased several outdoor rated plastic electric boxes. One was a plain double-gang box. The other two were 6″x6″x4″. The nice thing about the double-gang box is that it already has threaded holes on it for conduit adapters to thread right in. However, it’s a relatively small box, but big enough to connect my Enphase trunk cable to some standard 12 ga wire and send it down the conduit.

At the other two boxes, I need a little more space. There will be more total wires coming through and two of the three rows will be connected in parallel. Connecting them all together would be too much current for the 12 gauge wiring, whereas having each on its own would require another circuit. Those boxes are also deeper. That will allow space for connecting the conduit and having it run UNDER the racking.

IMG_4807The larger boxes are plain, there’s no holes in them. I drilled two 1 inch holes so that I could insert a threaded 3/4″ conduit connection. I also drilled a 3/4″ hole so that I could add a 1/2″ watertight connector for the trunk cable to enter. I also made sure to use silicon sealant at all the ports and the drilled holes to make sure they stay weather-proof.

Each of the three boxes just gets mounted to the Iron Ridge racking with self-tapping screws. This past Thursday, I attended some solar training sponsored by Iron Ridge and Enphase. I asked the Enphase representative about the “proper” way to attach junction boxes to the racking for their system and mentioned that I had trouble finding the right brackets. His response was that they used to make those but stopped because “Everyone just screwed the boxes right to the racking anyways…”

So, while just using a few screws to connect the boxes feels like a very low-tech solution and perhaps not the “correct” way, it turns out that’s how everyone was  doing it anyhow!

I also cut two pieces of 3/4″ plastic conduit to run from the top box to the middle one and from the middle to the bottom box. I’m still trying to figure out the best way to wrap the conduit around the edge of the roof and have it visually look okay. I might just buy some spare PVC conduit parts to have handy so that when I do get the electrician over, we can come up with a solution together while minimizing the time (and thus cost) of having the electrician there.

I also need some blocking to which I can attach my AC Disconnect. We don’t have the siding up yet , and we will want a nice flat surface for the disconnect. My brother (who is the one with all the construction experience, and acting as my general contractor for the garage) said that he would make up some blocking for me for the disconnect. Then we can put up the siding around it when we get to that point.

IMG_4809I haven’t cemented the PVC conduit yet. First, I just want to make sure that everything lays out right. I also ran into a problem with the 1/2″ waterproof connectors I was using for the trunk cable. The connectors are rated for cable thickness up to exactly the thickness of the cable that I’m using. When I was at the store, I even tested one on a sample piece of my cable. It worked fine in the store and again at home later. Of course, once I was on the roof, it was nearly impossible to thread on the connector. It was as though the cable was just a little too thick, and I couldn’t get the threads started. Even when I did, the plastic connectors would cross-thread and distort. I was able to get two of the three connectors to tighten down, although I wasn’t real confident with them. I might have to head back to the store and see whether or not the 3/4″ version of the same connector will work or not.

As it is right now, I’m expecting the electrician to come out at the end of the week. (Unfortunately, the weather report suggests thunderstorms that day!)

I’ve also been trying to nail down my roofer on a date. He did a fantastic job on the metal roof and has a man-lift which would be perfect to get the solar panels up. With my experience so far, I really don’t feel that there’s any good safe way to install the panels on the roof WITHOUT some sort of power equipment. The roofer would be able to provide both the equipment and the experience to operate it. He would also transport it to and from my property. Add that all up, and it makes more sense to hire a guy and his gear for a day then try to go rent something and transport it myself.

I talked to him last week. He’s been very busy too, but has promised me a day to work on my project. I’m hoping to hear back from him after the Memorial Day Weekend.

At this point, the solar project feels like it’s in a holding pattern. I’m also trying to think of the best way to make sure the solar panels go on STRAIGHT and LEVEL when I put them up. In my experience with things like shingling, we usually used measurements and chalk lines. With the solar panels up on the racking, there’s no easy way to compare them to a chalk line. (No idea how well that would work on a metal roof anyways!) Perhaps I’ll just stick a large square behind the panels and make sure it’s at a right-angle to the racking. I’m pretty confident on the overall racking installation. One other reason why I’d like to hire the roofer is not just for his man-lift, but also for the experience he has making things square and level.

The MREA Energy Fair is coming up real soon and my goal has always been to have the solar up and running by then. Besides the installation, I still need the electrical inspection AND have the Power Utility to do a test before I can commission the system. Who knows how long THOSE take to happen!

I hope that THIS becomes the week that I REALLY get something done on my solar, but it is heavily dependent on other people’s schedules…



Fall Protection

by Ben N on May 10, 2017


Probably my single biggest goal of building my own solar system is simply to NOT FALL OFF MY ROOF!

Once I got the first piece of solar racking up, I had a brace which let me get ON the roof. At that point, I realized that the metal roofing is INSANELY slippery and would NOT be walkable. Not only did I need some sort of roof jack, I also needed fall protection.

IMG_4430This past weekend, I took a three-day hands-on workshop-style Wind Turbine Class. I already knew the instructor, which is how I found out about the class. Fall protection and safety is a BIG DEAL in the wind industry, so I made sure to ask about fall protection (and how to best deal with it on my project.) In the end, I got a personal loan of an automatic retractor strap.

This device works much like a safety belt in a car – gently pull it and it moves – jerk it, and it locks in place.

The next thing I would have to figure out is how to attach the strap to the roof. Fall protection anchor points are commonly used for roofing, but are installed BEFORE the roof goes on, screwed right to the structure of the roof. I have a brand-spanking-new metal roof, which I don’t want to put any holes in. I do have two “extra” S-5! brand metal roofing clamps. The problem with using those is that they are really a permanent clamp. Once they are on, they are difficult to remove, and installation leaves a mark on the roof. (The set screw actually BENDS the roofing, which is what makes the clamp so powerful.)

IMG_4489So, one solution would be to install a clamp for fall protection, and leave it there permanently. The downside of that is having an ugly clamp there for all eternity. That actually got my mind going. What if there was some OTHER use for the clamp later? I was trying to figure out a way of using MULTIPLE clamps to span the ridge vent. In a web image search, I realized that what I wanted to do is actually similar to a weather vane mount! Perhaps I could install a few clamps, and then use them for a decorative weather vane later on!

I still didn’t know the best way to attach my fall protection to an S-5! clamp. I would need some sort of heavy welded ring or something similar to which I could hook the safety. I started looking around for what I had for materials and realized I had a piece of angle iron longer than 16″. I could drill two holes through the angle, attach an S-5! clamp to either end, and clamp the whole thing to the roof. This would give me a solid 16″ grab bar I could hook anything I want to.

IMG_4474I got out my drill and bit set and used the 1/8, 1/4, and 3/8″ bits to drill the two holes to size. Starting with the small bits and working my way up, it was SURPRISINGLY easy to drill the holes….. which was good, because I ended up doing it twice.

I fit the clamps to my drilled angle iron and tested the bolts. It all looked good.

Next, I needed to climb up onto the roof. My solar racking (being used as foot-holds) only extends half way up the roof. I pulled up a step-ladder and laid it flat on the roof, with the ladder’s feet braced against the top piece of racking. I crawled up to the peak, where I could stay in place by uncomfortably straddling the ridge. I installed both clamps rather close to the ridge, centered on the south face of the roof. This should keep the fall protection up above the top of my finished row of installed solar panels. When I went to bolt the bar to the clamps, I realized that the roofing is NOT actually spaced to exactly 16″ – it’s a hair less than that. I would have to climb back down, re-drill my holes, and come back up. Because the measurement was less than one hole diameter, I’d have to move over on the angle iron and drill a new pair of holes, instead of just one.

So, one more time, I drilled the holes and climbed back to the roof. This time, I was able to thread the bolts through the iron and torque them down into the clamps. The iron felt very solid on the roof.

IMG_4484Next, I connected the auto-retractor strap and hooked it the the climbing harness, which with some forethought, I was already wearing. I crab-walked down the roof to see how far I could get. Uh-oh. I couldn’t reach the bottom without running out of strap. On the device, part of the model number was “12″. I was afraid that it probably referred to twelve feet of reach with the strap, and I was right. My roof is about 18 feet from the peak to the eaves. I went and got my engine hoist lifting strap, looped that around my angle iron anchor, and then attached the fall protection device to it. This time, I was able to walk all the way down the roof to the ladder.

IMG_4483At that point, I can unhook the harness and then loop the auto-retractor to either the ladder or the lowest solar rack. Then I just need to make sure to walk down the ladder safely.

After once again checking everything over it seemed very solid and secure. The only thing I will likely do is add a piece of foam or some sort of padding under the retractor strap reel. If I move to the far edges of the roof, the reel slides around and can drag on the roof. It’s brand-new, and I’d like to keep it from getting scratched up!

I now feel MUCH more confident about safety on the roof.
No, I didn’t get any more of the racking installed, but I’m now ready to tackle the rest of it (as soon as I get some more time!) and can then begin installing the cabling and micr0-inverters.

Until next time, stay charged up!


PS: As I was finishing up, I did a few short controlled slides on my butt, lowering myself down the roof. Suddenly, I remembered the fact that when I was a kid, my Dad built us a homemade slide in the back yard. It was wood, covered with sheet metal used for roofing. I think the angle was even about what my roof is. The metal was dark brown and really soaked up the heat of the summer sun. We would go out to use the slide and get burned if we were wearing shorts. My typical hand-me-down corduroy pants slipped right down the slide, while preventing burns.

PPS: If I’m working on the upper part of the roof, I’ll reconnect the retractor directly to my anchor point. That way, there’s no slack due to the purple strap. Also, I did look up the real-world testing on the S-5 Clamps. For that style, and the type of roofing I’m using, each one will hold over 1,000 pounds, or 2,000 lbs for the two of them. In theory, I could suspend a Geo Metro from my roof.


Solar Racking Begins!

by Ben N on May 8, 2017


I finally had a chance to start installing the Racking!

My package with the S-5! clamps showed up, and I was able to begin the racking during two evenings of this past week.

Let’s state two things right off the bat:
1) I am NOT a professional. I do not make a living doing this sort of thing. While I have taken a solar class before, I’ve NEVER done a full-blown system all by myself.

2) I have never worked on metal roofs.

So, I’m making this up as I go….
On a typical asphalt shingle roof, a shingle can be lifted up, and a roofing jack can be slid under it. That’s held in place by a few nails UNDER the shingle. The jack in turn holds a wide wood board. This gives the worker a place to set down tools and materials without sliding off the roof. It’s also a great place to stop the human if he starts sliding a little.

IMG_4341So, on my METAL roof, the fact that it’s a single piece of roofing all the way up is actually a disadvantage – I can’t use roofing jacks! I decided to instead mount the first row of solar racking within arm’s-reach of the bottom edge of the roof. My spacing sketch allowed for the racking to go there, and I could install it from a ladder. I attached S-5! clamps to either end of the roof, then filled in the ones in the middle in a straight line compared to the ones on the end. Install a clamp, climb down the ladder, move the ladder, climb up the ladder, install another clamp; repeat.

The clamps are installed on every third rib of the roofing. The ribs are 16″ wide, and the spacing works out to supporting the racking every four feet. This means 8 clamps per row of racking. Once the clamps were all in place, I carried the 28′ long piece of racking (held right in the middle) straight up the ladder, set it on the clamps, and bolted it down. That’s the quick description. Again, it took a fair amount of time, working from the top of the ladder, moving the ladder, and repeating seven more times.

When I was done, I finally had a bar that would at least prevent me from sliding straight off the top of the roof. It looked very much like one of those “snow retainers” that keeps an avalanche of snow from sliding off metal roofing. With the first piece of racking in place, I was finally able to actually climb onto the roof. First, I put on a brand-new pair of shoes that I had bought after searching the entire store for the style with the most non-slip soles. The roof pitch is an odd one – 6.8:12 – the reasoning on that had more to do with weird zoning laws and height maximums. Let’s just say that my roof is between 6:12 and 7:12 in pitch.

I climbed up onto the metal and…… ZERO grip!

Seriously, it was like Teflon up there. I could put hardly any weight at all on my foot without immediately sliding. I COULD walk, hunched over, as long as my feet were right up against the racking. Even better, I could “crab-walk”. I faced downhill, sat my butt on the metal, and braced my foot on the racking. THAT felt secure. With my low center of gravity and foot position, I wasn’t going anywhere. In fact, it was rather nice laying up on the roof on a spring evening. That was enough work for one day.

The following evening, I was able to install the next two rows of racking.

IMG_4392This time, I placed a clamp at either end of the roof and stretched a string between the two of them. This would be my straight-edge to help me locate the rest of the clamps. I continued adding the clamps, lining them up with the string, and tightening them down. Next, I carried one piece of 14′ racking onto the roof and then bolted it in place. I then installed the splice in the other half while on the ground, carried it to the roof, slid the splice into place, and bolted down the second half of that row of racking.

Since I could now stand on the SECOND row of racking, it allowed me to reach up and start working on the third row. (The second row also made an excellent hand-hold when standing at the first row, heading up and down from the ladder.)

I was able to install the third row before it was starting to get dark.

IMG_4397By this point, I was pretty high in the air. A little lower down, with my foot-hold on the first row and hold-hold on the second, I felt fairly secure, but less so the higher I was going. Hmmmm. It’s probably time that I really think about safety here. Being an amateur should NOT mean simply being stupid. I knew that I had a climbing harness around (although everything that USED to be in my garage was now in storage, possibly at one of several different locations…) I figured that I could rig something up with a rope to the peak of the garage, or possibly over the top, back down to the ground.

The big reason why I didn’t get ANY work done on the garage this weekend was that I was off at a three-day workshop-style class on wind turbines. I already knew the instructor through the MREA and some other events. I asked him about ideas for fall protection, and ended up getting a loan of an aut0-retracting strap. The device is somewhat like a safety belt in a car – if you pull on it, it unrolls. If you let go of it, it retracts. But, if you jerk quickly on it, it locks into place – for example when you stumble and would otherwise be falling off the roof.

IMG_4470I showed my six year old daughter how this device would help keep me safe on the roof, and she insisted on testing it herself. A few minutes later, she was hanging from the ceiling of the garage.

As soon as I get some more time, I should be able to continue installing the racking – this time with some fall protection. Although I’m pretty solid on the roof, I still can’t WALK on it. That means I still need my hands to move around, which in turn means that I can’t have two hands free to carry solar panels. I plan to get all the racking, the micro-inverters, cabling, and everything else needed installed on the roof by myself. After that, we’ll need a crane/man-lift, etc. to safely install the solar panels. Most likely, I’ll hire the metal roofer for a day, along with his boom machine for us to get the panels onto the roof and in place.

Until next time, stay charged up! And no falling off roofs!



Solar Road Trip!

by Ben N on April 30, 2017

Today, we headed out on a road trip to pick up the solar panels for my garage.

My brother, Wayne, and I hitched up my multipurpose trailer to the van and hit the road to go see Phil Manke at Practical Solar in Wautoma, Wisconsin. Phil runs a solar hot water installation business. He also has quite a few other interesting project. (Take a look at the video for a glance at his stainless-steel solar focusing dish!) I met Phil a while back at the MREA Energy Fair, and somewhat recently found out that he had acquired a supply of new Helios brand solar panels. I was especially interested in these panels because they were manufactured in Milwaukee, Wisconsin, about 30 miles from my house.

Before heading out, I made sure the trailer was set up for the solar panels. I measured the trailer to make sure that two stacks of the panels would fit, and that the trailers was solid and level at those points. This is a modified trailer. (In it’s first life, I think it was a pop-up camping trailer.) I did need to make sure that the solar panels wouldn’t lay out right over the top of the wheels. If there was too much weight, the wheels could actually rub on the panels! To prevent that, I screwed 2×4′s down to the decking to space the panels up.

IMG_4307The drive from Oconomowoc to Wautoma was pretty uneventful. We first stopped for gas and coffee, as I borrowed the vehicle with very little gas in the tank. Filling the van, I realized that I just spent in one day what I don’t usually pay for gasoline in a month! Driving an electric car and occasionally a Prius, it’s actually gotten pretty hard for me to imagine how much money people can spend on gasoline every month!

We took the side roads on up, with an estimation of about 1 hour 45 minutes to get there. We stopped at Culver’s for lunch before heading to the outskirts of town to meet up with Phil.

Phil’s place is impressive in the kind of way that I like. Imagine an “Energy Farm”. Besides several large arrays of photovoltaic panels, there were also multiple solar hot-water setups, piles of sorted recyclable project materials, and other interesting eco-experiments, including a polished parabolic reflector mounted on a trailer and a wind turbine built from 55-gallon drums cut in half. Phil has the air of an Farmer/Inventor about him. He preaches about energy independence and common sense. A Patriot in overalls.

We pulled past the pole-barn warehouse to turn around the van and trailer. Then we positioned the trailer for easy transfer of the photovoltaic panels. Phil already had a number of them in his pickup, parked just inside the warehouse.

IMG_4315Loading the panels was very straight-forward. Just make sure they are stacked nice, and have the layers of cardboard between them to keep the frames from getting scratched up. Beyond that, it was just a matter of using plenty of ratchet straps to hold the load in place on the trailer.

It took about an hour to load all the panels, lash them down, pay for them, say our good-bye’s and be on the road again.

We took the same side-roads back home. Besides being able to drive a little slower than the interstate (thus improving fuel economy), it also meant that I felt safe if I needed to pull to the side of the road. We stopped in the first small town on the way and checked the straps. One had loosened a little, and the rear stack of panels had shifted just a bit. I put a spacer between the two stacks of solar panels (a shorty two-step step-ladder) and tightened the straps back down. The load felt solid, and we continued home. Other than a bathroom break, we didn’t make any more stops. The day was rainy and the rest of the trip was completely uneventful. Which is a good thing. I like when things go wrong, as they make the best stories, but in this case, I was happy just to get home with no further adventure.

IMG_4325In my driveway, I backed up the truck and we rolled the trailer right into the garage. There was really no reason to unload the panels from the trailer. If they need to be moved to make space for some additional building supplies (the garage isn’t even sided yet!) we can still move the trailer around.

Since I now have the panels themselves, I have NEARLY everything I need to start installing my photovoltaic system. I have the racking, the micro-inverters, the panels, the disconnect, I even have the Envoy communications gateway for the Enphase system. The only thing I’m still waiting on is the cables that the micro-inverters plug in to and the S-5! brand clamps that will connect to my metal roof.

In the mean time, I’ve just been busy (work, a college class with upcoming final, a Kickstarter campaign, a wind turbine workshop, etc.)

I look forward to actually getting everything together!

These solar panels are Helios model 6T-260. They are typical 60-cell solar panels rated at 260 watts. They cost me $150 each. That works out to 58 cents per watt, if you want to look at it that way. The faceplate power of these panels in total is 6,240 watts. Of course, real-world conditions, inefficiencies, etc bring that down a bit. At this time, I was able to find a good deal on some German-made solar panels for not too much more money, but those also have to be shipped half-way around the world. I was much more interested in getting solar panels make near me. Higher wattage solar panels are also available right now, but can cost considerably more per watt. I decided it was in my best interest to stay on budget!

Until next time, stay charged up!


PS: Too bad this was too far away for me to tow with the iMiEV! If I had a Tesla Model X, I could have driven there and back while towing on a single charge! Oh well, I’ll make up for the gas when I start producing electricity!


Solar Experimenting

by Ben N on April 9, 2017

Spring is Sprung!
It was the first Saturday of spring with some actual nice warm sunny weather, so that means it’s time to experiment with solar!

A couple of weeks ago, I got a few used Enphase micro-inverters in the mail. My buddy, Russ, (https://www.youtube.com/user/rwg42985) had found some inverters at an electronics salvage yard near him. He tried testing a few, but wasn’t able to get them to work. After doing a little research, I found conflicting reports on whether or not this type of inverter was usable at all without first “commissioning” it with an IT device. Since I was planning on ordering Enphase’s Envoy for my system anyways, I just went ahead and ordered one.

I had also already purchased a pair of Helios 260w solar panels. (The Helios brand was manufactured in Milwaukee, Wisconsin, about 30 miles from my house.) So, with solar panels, micro-inverters, Envoy, and a sunny day, there was nothing stopping me from hooking them all up and making power!

IMG_3503One last part of the Enphase micro-inverter system is a special cable with quick connectors on it that the micro-inverters plug in to. I bought a section of that cable with two connectors on it at the same time as the Envoy. I picked up some parts from the electric aisle of the Home Improvement store to wire the cable up to a junction box and a NEMA 14-50 plug. That’s a heavy 240V connector that’s common at RV parks. It also happens to be the style of electric outlet I have in my garage for my electric car charging cord (EVSE.)

IMG_4004The first step was to get the Envoy up and running. The device is an internet gateway. It communicates with the micro-inverters to set up the system and then output system data to the web change settings and view solar energy production information. The Envoy communicates with the inverters over the power line. That means that the device has to be connected to a “clean” outlet. You don’t want to plug the power cord into a surge protector or a circuit with any electric motors or anything else that can muddy the signal. I happen to have a dedicated outlet right next to my household breaker box which I was using with my T.E.D. whole-house energy monitor. (The T.E.D. uses a similar style Data-Over-Power communications system.)

IMG_4012I downloaded Enphase’s “Toolkit” app to my smartphone. I could then communicate from my phone to the Envoy over wireless to set it up. One of the first things was a software update. That took at least a good 20 minutes. Enphase recommends installing the Envoy and having all software updates done before connecting any micro-inverters. Setting up the Envoy with the app was straight-forward. The app even included a few brief videos showing an installer exactly what to do.

Back out in the garage, I propped my two solar panels against the wall and into the sunlight. The micro-inverters were already plugged in to the solar panels. I only had to plug the inverters into the trunk cable, and then plug that into the wall with the NEMA 14-50 plug. I then flipped on the breaker for that circuit.

At that moment, I was NOT producing any solar power. The inverters have several safety features. A big feature is “Anti-Islanding”. The inverter must sense that it is connected to grid power. If it doesn’t, the inverter instantly shuts down. This prevents the solar panels from pushing electricity out to the grid during a black0ut. Once power is restored to the grid, there’s still a timeout feature that prevents the micro-inverter from generating power for five minutes AFTER good clean power is restored. (The inverter also will not output if grid power is out of voltage or frequency range, such as in a brown-out.)

So, although I just turned on the circuit breaker for the inverters, the solar panels wouldn’t make power for another five minutes. After that though, the small green LED on the inverters was flashing green, indicating that all was functioning correctly. In the Enphase Toolkit app, I could see how much power I was making from each panel. (I also used the clamp-on ammeter feature of my multimeter to check current flowing through the trunk cable.)

Screen Grab half day of solarOnce the system “commissioning” was done, I could then take a look at my power production through Enphase’s “Enlighten” software. The Envoy pushes data from the inverters out to the web, allowing the solar owner to view production information on it from anywhere in the world. A person can also make that data public (if they so wish) so that friends can see how much solar power is produced as well.

By actually connecting all these components, I have a much better sense of how they work, and how I’ll create my full-blown home photovoltaic system. Still, there’s a few quirks…

For one thing, two of the three salvaged inverters use H4 connectors. These are supposed to be interchangeable with the MC4 connectors on the solar panels, but they are just a tad different. For the life of me, I can’t figure out how to unplug them! I have all the various H4 and MC4 unlock tools, but they just don’t seem to work! If anyone has ever done this, please let me know how!

IMG_4011I’m also trying to decide exactly which inverter I want to purchase. M215 and M250 inverters are basically named for how many watts of power they can handle. One would assume that a 260 watt solar panel is more powerful than a 250 watt inverter, but this isn’t necessarily true. For one thing, a panel rated at 260 watts is in “ideal laboratory conditions”… which seldom happen in the real world. In my experimenting so far on a sunny morning, manually tilting solar panels to match the angle of the sun, I wasn’t often getting all that much more than 200 watts per panel. (At one point, I did hit 235 watts!)
The M250 inverter is designed to handle 240w maximum continuous, while the M215 handles 215 watts continuous, 225 watts peak. (And yet I hit 235 watts using a 215 inverter!)
It would appear that M215 inverters might be just fine with these 260 watt solar panels, and they cost less than the M250s. For a more technical angle on why, take a look at Enphase’s white paper on this. It’s an interesting read. Let me know what you think of it. (You can read that paper at: https://enphase.com/en-us/support/technical-brief-sizing-solar-modules-microinverters)

Looks like I’m getting very close to actually buying my solar panels and ordering racking and inverters. Some of the best mail-order prices for solar components can be found at Renvu (http://www.renvu.com). At this point, I’m planning on ordering inverters from them, but will probably get my racking locally to save on shipping costs.

Until next time, stay charged up!