Let's talk about solar power... (purchases, calculator, rooftop)

[Juram]

Originally Posted by HX_Guy

So I received the proposals from the different companies. The system sized are all over the place because some companies quoted to cover 100% of usage, others 85%-90% and others just enough to cover on-peak usage.

Off the bat the Company 6 proposal using the Canadian Solar seems great and pretty shocking price wise. I understand Canadian Solar is a decent panel too.

Seems like I should disregard the Hanwha, LG and Hyundai panels as for the price I can get equal or better. Any other thoughts or input? Thanks.

Wow....that's a crazy price differential for Company 6. $2.59 a watt is insane, I mean, wow. To put that into perspective, back around 2009 the pricing was about $6.00 a watt. I don't know that you can put together a system yourself for less than that honestly. TL inverters are also a plus since they tend to fare better in a hot weather climate.


Company 4 is offering SunPower for less than Hyundai panels? Are you sure that isn't a typo? If you can get SunPower for $3.09, I'd certainly think long and hard about it, that is a remarkable price for very high end panels. No need for a system that big thoug I don't think.


I think the LG price is a fair one for pretty high quality panels. Not really familiar with Hanwha but I'm guessing generic Chinese modules.


Company 5 seems like a ripoff quite frankly, their pricing is way off kilter.

[HX_Guy]

Oops, you were right, that was a typo for company #5. The Hyundai panels total price was $31,572 or $2.43 per watt, a new low!

Company 5's system costs are somewhat high but their financed cost per kW is actually the best, at least on the Canadian Solar panels.

[Juram]

Originally Posted by HX_Guy

Oops, you were right, that was a typo for company #5. The Hyundai panels total price was $31,572 or $2.43 per watt, a new low!

Company 5's system costs are somewhat high but their financed cost per kW is actually the best, at least on the Canadian Solar panels.

[Potential_Landlord]

Originally Posted by HX_Guy

We used around 21,000 kWh per year so we need about a 12 kW system if we want 100% coverage.

This is one mockup of the layout we can have which would be a 12.4kW system using 38 327W panels.
Due to the neighbor's stupid two story house south of us, we can't use the majority of the south facing roof.

Thanks, very interesting. Did you figure in the 3 feet distance to the roof edges as per City of Phoenix code or is this not applicable for you? That is a big problem for me - not enough south / west facing roof space.

[HX_Guy]

Yes, Peoria has the same code (it's actually Fire Dept code). It only applies to the ridge though (the top side parallel to the eve). The hips and valleys have an 18" setback rule unless there will be no panels on the adjacent roof surface, in which case there is no setback requirement.

[HX_Guy]

Here is my analysis of the expected production of the panels on the south roof with the shade problem. I used Sketchup to see when the neighbor's house would shade the different sections of panels (should be very accurate as it's to scale and it matched today's shadow ).








The only panels that should be on the south roof are the yellow section ones, they will produce more than if those 6 panels were placed on an east/west surface. Everything else, it makes more sense to place east/west. The 14 panels in the brown section would fit perfectly on the east surface (14 is the max I can get on there). Additionally I can get another 14 panels facing south on the north roof and patio cover, total would be 28. I'd like a total of 36 panels (for a 11.772 kW system) and I could fit those additional 9 on the west facing roof (canceling out the blue section)...not sure if the additional 529 kWh per year is worth it visually though having those panels on the west roof, probably not.

Other thing is figuring out the stringing...in an ideal world I could do the above setup but I know it won't be possible, have to figure that part out.

[Potential_Landlord]

Originally Posted by HX_Guy

Here is my analysis of the expected production of the panels on the south roof with the shade problem. I used Sketchup to see when the neighbor's house would shade the different sections of panels (should be very accurate as it's to scale and it matched today's shadow ).








The only panels that should be on the south roof are the yellow section ones, they will produce more than if those 6 panels were placed on an east/west surface. Everything else, it makes more sense to place east/west. The 14 panels in the brown section would fit perfectly on the east surface (14 is the max I can get on there). Additionally I can get another 14 panels facing south on the north roof and patio cover, total would be 28. I'd like a total of 36 panels (for a 11.772 kW system) and I could fit those additional 9 on the west facing roof (canceling out the blue section)...not sure if the additional 529 kWh per year is worth it visually though having those panels on the west roof, probably not.

Other thing is figuring out the stringing...in an ideal world I could do the above setup but I know it won't be possible, have to figure that part out.

Are you going with micro-inverters? Then stringing is much easier.

[Juram]

Originally Posted by Potential_Landlord

Are you going with micro-inverters? Then stringing is much easier.

They're also pricier and have a higher rate of failure in desert conditions. Micro-inverters are mostly intended for places with cooler climates. The rub is that while you receive a 25 year warranty with pretty much every single micro-inverter, they only cover the replacement cost. If the unit goes out, the onus is on you to get up there on the roof and remove and then replace the damaged unit or you have to get someone else to pay to do it. That was a big turn-off for me. I hate getting up on my roof for anything, much less to mess around with heavy panels and electric wiring.

Enphase’s return shipment of the repaired or replacement product, whichever is later. The LimitedWarranty covers a replacement unit to replace the Defective Product, but does not include labor costsrelated to (1) un-installing the Defective Product or (2) if applicable, re-installing a repaired or replacement product.

M215 WARRANTY

[Potential_Landlord]

Originally Posted by Juram

They're also pricier and have a higher rate of failure in desert conditions. Micro-inverters are mostly intended for places with cooler climates. The rub is that while you receive a 25 year warranty with pretty much every single micro-inverter, they only cover the replacement cost. If the unit goes out, the onus is on you to get up there on the roof and remove and then replace the damaged unit or you have to get someone else to pay to do it. That was a big turn-off for me. I hate getting up on my roof for anything, much less to mess around with heavy panels and electric wiring.

Juram: I cannot thank you enough for bringing your solar expertise to this board and sharing it with us!!! You give us so many good hints, it's incredible. you know my big challenge with solar is the missing roof space. What do you think about the racks that they use on the parking lots? We could combine having a shaded gazebo in the back yard with solar power production. It would also be high enough to be safe for kids etc. Would that be cost prohivitive? - Also thanks for HX_Guy for sharing his experience with us.

[Juram]

Originally Posted by Potential_Landlord

Juram: I cannot thank you enough for bringing your solar expertise to this board and sharing it with us!!! You give us so many good hints, it's incredible. you know my big challenge with solar is the missing roof space. What do you think about the racks that they use on the parking lots? We could combine having a shaded gazebo in the back yard with solar power production. It would also be high enough to be safe for kids etc. Would that be cost prohivitive? - Also thanks for HX_Guy for sharing his experience with us.

You could build a structure to hold them, sure, as long as you got it permitted through the city or county and your HOA if you have one.


Also, another issue that comes into play is property taxes. Solar on your home is exempt for the purposes of property tax valuation. However if you build a structure and put the solar on that, from my understanding that exemption basically goes out the window.

At the very least it'd be worth calling the Assessor's Office or speaking with a tax accountant to confirm that exemption.