live4soccer7
Solar Enthusiast
- Joined
- Jun 15, 2020
- Messages
- 670
Ok. I have been wanting to do this for years now since I have moved into my current location which I will be until I physically can't be here anymore. I have some things planned.
Location: Spokane, WA 99022 (Eastern WA)
I am still deciding on a source for panels and exactly which panel I would like, but I have been working on some of the details and will begin pulling the trigger on purchases before long.
I would like any input/advice as this will be my first time installing and working with solar.
My area is quite open as far as sun and potential blockages with that only happening early in the morning and late in the evening. I will be going with a string inverter setup.
I'll probably go with the SMA Sunny Boy Inverters. I can currently get them for about $1360 for the 7.7kw configuration. I will need 4 of these. I am open to alternative inverters if anyone has input. I will run two strings into each inverter (I believe the can accept 3 different strings). I did some calculations based on a 320w panel with temperature taken into consideration and it had an optimal string size of 9-11 panels.
Is it best to be on the upper end of that spectrum if the physical configuration allows? I would think that as the panels age then the voltage would drop a little bit, so being on the upper end would probably be better. Doing stings of 10-11 depending on the requirements.
Ideally, I would like a ground mount system that I could have two tilts for a summer and winter tilt. Anyone that has a ground mount system, have you found this to be worth it? There is quite a swing in the sun's location where I am between winter and summer, so I would think that this could increase output by a decent amount by just changing it for summer and winter months.
I am considering the UniRac GFT racking system. Based on their building application online it should be about $6k for the ground mount infrastructure plus installation. I can rent an augur to set the posts and pour concrete. I'd imagine that will probably run about $1500 with concrete. I suppose, I could look into getting a post driver attachment for the skidsteer and that would save concrete and maybe cheaper and easier if I don't run into rock. Again, I am open to suggestions on the racking system. I know iron ridge is popular, but I talked to a local solar dealer and they said the pipe is unbelievable expensive right now for the main support. I'm not sure that the UniRac GFT system is meant to "tilt" after installation and setup. I'm kind of thinking no. GFT (Ground Fixed Tilt). This system is what my local rep referred me to and said it is getting a lot of good feedback. I'm not sure I want to go with something home made on this as it would take a lot of time and I don't quite know what the local permitting will need for my county.
On to the Panels. This is where I get hung up. I can get panels from bluesunpv (china supplier) for about $11k and also get the wiring and MC4 connectors for an additional $1400. They are 455W panels (57-58 panels), which would mean I could get away with a smaller ground mount configuration and save some money there as well (about $1500). Otherwise I can go with something available locally around the 320W range Hanwha Q-Cell G5 315W for about $14k (80 panels). I'm kind of at a loss on panel selection due to pricing. I can make the calculations etc.... That isn't a problem.
Component location logistics - I would think that it would be best to have the inverters closer to the grid tie meter as opposed to closer to the panels. The array will be roughly 300 feet away from the meter. I can get the inverters within about 40' or so of the meter for my ideal location. I suppose I could get them closer, but if not necessary then I'd like to keep them at that 40' location. Is my thinking correct on this?
Array Orientation - I have attached a photo to show where I want to put the array. Location information:
The field as you go east has a gradual incline and then there is a larger hill across the road. II plan to have a shop in the eastern portion of the field and I believe it won't shad the panels at all or for too long in the morning due to the hill that is further east anyways that I can not control. The big building to the south does not block the sun in the winter. Only do the buildings to the west block the sun in the very end of the evening. I think I have picked the ideal location given these things. Again, open to suggestions.
My next question is the orientation of the actual array. Everyone always says to point your panels south, which is exactly perpendicular to the driveway. Is there a more scientific way to calculate this based on my actual lat and long? Same goes for the optimal tilt on the panels if I were to only use a single angle all year.
Incentives: 26% Federal Tax Credit and WA Sales tax exemption on solar components/installation/systems
I did just find this information:
To optimize overall production year-round, tilt your panels at your latitude. To lean toward more production in the summer, tilt your panels at your latitude minus 10-15°. To lean toward more production in the winter, tilt your panels at your latitude plus 10-15°.
Location: Spokane, WA 99022 (Eastern WA)
I am still deciding on a source for panels and exactly which panel I would like, but I have been working on some of the details and will begin pulling the trigger on purchases before long.
I would like any input/advice as this will be my first time installing and working with solar.
My area is quite open as far as sun and potential blockages with that only happening early in the morning and late in the evening. I will be going with a string inverter setup.
I'll probably go with the SMA Sunny Boy Inverters. I can currently get them for about $1360 for the 7.7kw configuration. I will need 4 of these. I am open to alternative inverters if anyone has input. I will run two strings into each inverter (I believe the can accept 3 different strings). I did some calculations based on a 320w panel with temperature taken into consideration and it had an optimal string size of 9-11 panels.
Is it best to be on the upper end of that spectrum if the physical configuration allows? I would think that as the panels age then the voltage would drop a little bit, so being on the upper end would probably be better. Doing stings of 10-11 depending on the requirements.
Ideally, I would like a ground mount system that I could have two tilts for a summer and winter tilt. Anyone that has a ground mount system, have you found this to be worth it? There is quite a swing in the sun's location where I am between winter and summer, so I would think that this could increase output by a decent amount by just changing it for summer and winter months.
I am considering the UniRac GFT racking system. Based on their building application online it should be about $6k for the ground mount infrastructure plus installation. I can rent an augur to set the posts and pour concrete. I'd imagine that will probably run about $1500 with concrete. I suppose, I could look into getting a post driver attachment for the skidsteer and that would save concrete and maybe cheaper and easier if I don't run into rock. Again, I am open to suggestions on the racking system. I know iron ridge is popular, but I talked to a local solar dealer and they said the pipe is unbelievable expensive right now for the main support. I'm not sure that the UniRac GFT system is meant to "tilt" after installation and setup. I'm kind of thinking no. GFT (Ground Fixed Tilt). This system is what my local rep referred me to and said it is getting a lot of good feedback. I'm not sure I want to go with something home made on this as it would take a lot of time and I don't quite know what the local permitting will need for my county.
On to the Panels. This is where I get hung up. I can get panels from bluesunpv (china supplier) for about $11k and also get the wiring and MC4 connectors for an additional $1400. They are 455W panels (57-58 panels), which would mean I could get away with a smaller ground mount configuration and save some money there as well (about $1500). Otherwise I can go with something available locally around the 320W range Hanwha Q-Cell G5 315W for about $14k (80 panels). I'm kind of at a loss on panel selection due to pricing. I can make the calculations etc.... That isn't a problem.
Component location logistics - I would think that it would be best to have the inverters closer to the grid tie meter as opposed to closer to the panels. The array will be roughly 300 feet away from the meter. I can get the inverters within about 40' or so of the meter for my ideal location. I suppose I could get them closer, but if not necessary then I'd like to keep them at that 40' location. Is my thinking correct on this?
Array Orientation - I have attached a photo to show where I want to put the array. Location information:
Height: | 741m | Set Lat/Lon |
Lat: | N 47°33'0.61'' | 47.55017° |
Lng: | W 117°38'58.49'' | -117.64958° |
UTM: | 11T 451125 5266510 | |
TZ: America/Los_Angeles DST PDT |
The field as you go east has a gradual incline and then there is a larger hill across the road. II plan to have a shop in the eastern portion of the field and I believe it won't shad the panels at all or for too long in the morning due to the hill that is further east anyways that I can not control. The big building to the south does not block the sun in the winter. Only do the buildings to the west block the sun in the very end of the evening. I think I have picked the ideal location given these things. Again, open to suggestions.
My next question is the orientation of the actual array. Everyone always says to point your panels south, which is exactly perpendicular to the driveway. Is there a more scientific way to calculate this based on my actual lat and long? Same goes for the optimal tilt on the panels if I were to only use a single angle all year.
Incentives: 26% Federal Tax Credit and WA Sales tax exemption on solar components/installation/systems
I did just find this information:
To optimize overall production year-round, tilt your panels at your latitude. To lean toward more production in the summer, tilt your panels at your latitude minus 10-15°. To lean toward more production in the winter, tilt your panels at your latitude plus 10-15°.
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