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Hey guys,
I live in Central Virginia and have decided to go all in on a grid tied solar system. VA does not allow residential systems to be any larger than 20kW, so that is the size I'm going with, which will almost meet my annual energy needs. Here's my 2015 and 2016 usage to date:
I have been an avid fan of Ubiquiti products for a number of years and have a lot of their UniFi gear deployed in my house (Wifi Access Points, Switches, Gateway and central management). So I was exited when they released their sunMAX product line at a price of about $1,50 per watt (includes everything but the installation itself).
I spent the last few months prepping. I originally had 2 400A services on my property, one feeding my house (with 2 200A panels) and the other feeding my shop building with a single 200A panel, but with provisions for adding in a 2nd 200A panel in the future if I added a large welder or something along those lines. Spent quite a bit of time talking to my POCO (CVEC) about my solar plans, and they would not let my install the panels on my shop roof and then apply the credit from the power generated there my residence which uses the most power by far (above spreadsheet is just the house). So I had them drop the service from the pole that was feeding the shop, and I dug up the 3 500 MCM cables the 200 ft back to the shop meter base and then dug a new trench up to the house, to tie into that service.
It was a lot of hard work, but that part is finally done. Here's a shot of the run from the shop to the house, and you can also see the original run going over to the power pole running to the left.
At the house, the POCO dropped off a new meter base for me, and I then purchased and installed a 400A fused disconnect, and a 400A automatic transfer switch for the 2 x 200A service into the house. Here's a shot of that work being completed and me getting ready to pour a pad for my generator. My girls are 4 and 5, so as you can see, those are some decent size panels. It was a challenge to mount those solo and run the wiring, most of which was 300 MCM Cu!
Everything has been approved by the AHJ so far and the POCO has also signed off on my 20kW system. All the parts are ordered and should be arriving sometime next week, at which point I'll begin the install. Here's a schematic of the overall system:
The diagram is not 100% accurate in that my original plan had me doing 60 panels for the 15kW system, but I changed my mind and upped it to a 80 panel 20kW system. I made this decision after running PVWatts and discovering that putting 20 panels on my North facing shop roof (12:4 pitch or 18.4 degree angle) would actually generate a pretty decent amount, and then me to the point of being able to produce all the energy I am consuming.
I did 3 scenarios in PVWatts as seen below:
In all 3 scenarios, I have 56 panels on the South facing shop roof, plus an additional 24 panels in different configurations, going from least efficient to most.
Scenario 1 has the 24 panels at 20 degrees azimuth, which generate 6,700 kWh annually.
Scenario 2 has the 24 panels at 180 degrees azimuth, which generate 9,450 kWh annually.
Scenario 3 has the 24 panels on a 2 axis tracker, which generate 12,900 kWh annually.
Given the cost of a 2 axis tracker that can hold 24 60 cell panels, I'm pretty much ruling out option 3. But I'm torn between option 1 and 2. Option 1 is the easiest of course, but option 2 would not be too bad. It would basically involve me building a car-port like structure with a single shed roof leaning directly to the South with an angle of about 31.5 degrees (I'm at 37.33). The PSWatts calculation above shows it at 18.4 degrees like the shop, but it does not change that much. I have plenty of space, no shade to speak of.
So is it worth building the car-port to get that extra 2,750 kWh of annual production? I figure I can do it for around $1,000, so it would pay of itself in 3-4 years, and I would have a place to park my trailer, and or store some of my tractor implements that don't fit in the shop building at the moment.
And finally, there seems to be very little love for sunMAX on this forum. I hope I didn't make a mistake going with their product, but $28k delivered for a 20kW system seemed like a really good deal, and I have not really heard anything bad about the sunMAX product and I have had great luck with the rest of their products.
P.S. 4 years ago, I installed a Trane XL20i heat pump with a 20 SEER rating. It contains 2 compressors, so for stage one heating or cooling, it only runs the smaller one. This helped a lot with my electric bill. When they installed it, they also did an assessment of the house overall and found level of insulation, doors, windows, etc, to up to par with little to be gained. I have a pond with a pump, a pool with a pump, and servers and network equipment in the basement that runs most of the time that I can't really do anything about. Almost all my lights are LED at this time.
I do have a sense on order (sense.com), which will allow me to identify all my power consumers to see if there is anything else I can do to cut my consumption further. But the house is large and I live with 4 females, so there is only so much I can do.
Thanks!
Peter
I live in Central Virginia and have decided to go all in on a grid tied solar system. VA does not allow residential systems to be any larger than 20kW, so that is the size I'm going with, which will almost meet my annual energy needs. Here's my 2015 and 2016 usage to date:
I have been an avid fan of Ubiquiti products for a number of years and have a lot of their UniFi gear deployed in my house (Wifi Access Points, Switches, Gateway and central management). So I was exited when they released their sunMAX product line at a price of about $1,50 per watt (includes everything but the installation itself).
I spent the last few months prepping. I originally had 2 400A services on my property, one feeding my house (with 2 200A panels) and the other feeding my shop building with a single 200A panel, but with provisions for adding in a 2nd 200A panel in the future if I added a large welder or something along those lines. Spent quite a bit of time talking to my POCO (CVEC) about my solar plans, and they would not let my install the panels on my shop roof and then apply the credit from the power generated there my residence which uses the most power by far (above spreadsheet is just the house). So I had them drop the service from the pole that was feeding the shop, and I dug up the 3 500 MCM cables the 200 ft back to the shop meter base and then dug a new trench up to the house, to tie into that service.
It was a lot of hard work, but that part is finally done. Here's a shot of the run from the shop to the house, and you can also see the original run going over to the power pole running to the left.
At the house, the POCO dropped off a new meter base for me, and I then purchased and installed a 400A fused disconnect, and a 400A automatic transfer switch for the 2 x 200A service into the house. Here's a shot of that work being completed and me getting ready to pour a pad for my generator. My girls are 4 and 5, so as you can see, those are some decent size panels. It was a challenge to mount those solo and run the wiring, most of which was 300 MCM Cu!
Everything has been approved by the AHJ so far and the POCO has also signed off on my 20kW system. All the parts are ordered and should be arriving sometime next week, at which point I'll begin the install. Here's a schematic of the overall system:
The diagram is not 100% accurate in that my original plan had me doing 60 panels for the 15kW system, but I changed my mind and upped it to a 80 panel 20kW system. I made this decision after running PVWatts and discovering that putting 20 panels on my North facing shop roof (12:4 pitch or 18.4 degree angle) would actually generate a pretty decent amount, and then me to the point of being able to produce all the energy I am consuming.
I did 3 scenarios in PVWatts as seen below:
In all 3 scenarios, I have 56 panels on the South facing shop roof, plus an additional 24 panels in different configurations, going from least efficient to most.
Scenario 1 has the 24 panels at 20 degrees azimuth, which generate 6,700 kWh annually.
Scenario 2 has the 24 panels at 180 degrees azimuth, which generate 9,450 kWh annually.
Scenario 3 has the 24 panels on a 2 axis tracker, which generate 12,900 kWh annually.
Given the cost of a 2 axis tracker that can hold 24 60 cell panels, I'm pretty much ruling out option 3. But I'm torn between option 1 and 2. Option 1 is the easiest of course, but option 2 would not be too bad. It would basically involve me building a car-port like structure with a single shed roof leaning directly to the South with an angle of about 31.5 degrees (I'm at 37.33). The PSWatts calculation above shows it at 18.4 degrees like the shop, but it does not change that much. I have plenty of space, no shade to speak of.
So is it worth building the car-port to get that extra 2,750 kWh of annual production? I figure I can do it for around $1,000, so it would pay of itself in 3-4 years, and I would have a place to park my trailer, and or store some of my tractor implements that don't fit in the shop building at the moment.
And finally, there seems to be very little love for sunMAX on this forum. I hope I didn't make a mistake going with their product, but $28k delivered for a 20kW system seemed like a really good deal, and I have not really heard anything bad about the sunMAX product and I have had great luck with the rest of their products.
P.S. 4 years ago, I installed a Trane XL20i heat pump with a 20 SEER rating. It contains 2 compressors, so for stage one heating or cooling, it only runs the smaller one. This helped a lot with my electric bill. When they installed it, they also did an assessment of the house overall and found level of insulation, doors, windows, etc, to up to par with little to be gained. I have a pond with a pump, a pool with a pump, and servers and network equipment in the basement that runs most of the time that I can't really do anything about. Almost all my lights are LED at this time.
I do have a sense on order (sense.com), which will allow me to identify all my power consumers to see if there is anything else I can do to cut my consumption further. But the house is large and I live with 4 females, so there is only so much I can do.
Thanks!
Peter
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