4.5kW SolarEdge/LG System coming soon to San Diego

[thejq]

I would look at it this way.

For panel upgrade, it's $1800 - 30% = $1260 today. If you know you will upgrade at some point in time (either because of panel upgrade, EV or pool), you will pay $1500+ later without any rebates which is $240+ more. By saving $1260 today, can you make $240 out of it by the time you finally decide to upgrade? Also have you thought about why your installer can charge more than the competitor for panel upgrade and still be in business for 25+ years?

As for inverter, by going with SE3800 you save $140 - 30% = $98. If you have to upgrade in 5 years, you have to get an new inverter. Will it be more advanced and cheaper? Yes, most likely. But will it be less than $98? Can you really sell a used inverter to recover some cost? I don't think so. Also SE3800 outputs 4.1KW max, so occasionally you will be clipped, granted maybe very small amount.

If it were me, option 3 seems to be the clear winner.

[PVAndy]

Got you. With SE, if you plan to expand later, you just have to get a slightly larger inverter to begin with. The price incremental is not that bad, eg. from SE5000 to SE6000 is about $100. With optimizer you can add panels with different brand and wattage just like microinverter. With microinverter, you still need to plan ahead if you want to add more later. Because microinverter always output 240v, the more you add, the higher the current going to the main breaker panel. So you need to start with larger gauge wire for expansion later. With optimizer, the DC voltage will increase as you add more panels, so the DC current only increases slightly, and you save a little bit on wiring.

I know this is an old post but I just wanted to clarify one thing. With SolarEdge optomizers it's the voltage of the string that remains constant and the current that increases as you add more panels. The Optomizers require a minimum of 8 in a string and string length maxes out at 5200W DC STC.

The string voltage is relatively constant at 350V DC and the Operating String current maxes out at 15 A. 350V x 15 A = 5250 W so the numbers aren't quite exact.

Also I think it's clear, but some earlier posts asked if the system was using optomizers. SolarInverters will only work with optomizers they are an integral part of the system. The entire MPPT function is performed by the optomizer.

Andy

[sensij]

By saving $1260 today, can you make $240 out of it by the time you finally decide to upgrade?

The answer to that question is yes, if the upgrade is 5 years from now, and the 1260 can be put to work in way that yields >3.5% / year.

[thejq]

The answer to that question is yes, if the upgrade is 5 years from now, and the 1260 can be put to work in way that yields >3.5% / year.

But that 3.5% has to be take home money. Since we all pay taxes, let's assume 20% tax (fed + state) rate (check with http://www.tax-brackets.org/californiataxtable at the bottom there's a calculator). But there's inflation too, and it's projected to be 1.7% for 2015. So 3.5/0.8+1.7 = 6.075%. If you can find a guaranteed investment instrument that gives you 6.075% return for 5 years, do let me know. For ref, 5 year US treasury bill pays roughly 1.6%.

[sensij]

But that 3.5% has to be take home money. Since we all pay taxes, let's assume 20% tax (fed + state) rate (check with http://www.tax-brackets.org/californiataxtable at the bottom there's a calculator). But there's inflation too, and it's projected to be 1.7% for 2015. So 3.5/0.8+1.7 = 6.075%. If you can find a guaranteed investment instrument that gives you 6.075% return for 5 years, do let me know. For ref, 5 year US treasury bill pays roughly 1.6%.

There are ways money can be put to work that do not incur income taxes or get penalized by inflation. If a panel upgrade was absolutely certain 5 years from now, I would think harder about this. If there is any optionality to it (and in my experience, 5 years is a long time to look ahead and think *anything* is certain), I wouldn't do it. I respect your opinion and I think it is great that subdriver97 is getting opposing points of view to consider. Whatever is decided, it is clear that it will be well thought out, which is as much as any of us can strive for, I think.

[SoCalsolar]

Not every AHJ

How did you come up with the 45amps for solar? It's center-fed so limited to 100% of busbar rating, so max of 25A for solar with a 100A main supply, no?

Not every AHJ(Authority Having Jurisdiction) limits center fed main panels to amps created by derating. Some treat them just as you would a main panel with the main breaker at the top or bottom of the panel. For example the county of Riverside treats a center fed just as it would any other main panel however some of the cities within the county do not such as Temecula, Sun City etc do not and sometimes it just depends on your inspector. Your issue is not the size of the main panel but the placement of the main breaker. How your AHJ treats this situation is the first bit of info you will need to know. If your contractor is on their game they will know this. The second option using your existing panel is if possible, to relocate the main breaker to the either the top or bottom of the panel. This is not always possible. The third option is a main panel upgrade. You should be fine with a 125 amp panel now and for future panel increases as a 125amp derated to 100 amp if the main breaker is located at the top or bottom of the panel then you have 45-50 amps to back feed solar. With 45-50 amps you could put in a SE7600 and still be fine.

[SoCalsolar]

12 year warranty on SE inverter

(However, the fact that SolarEdge offers a warranty extension makes me think that these units are engineered to last 20-25 years and very well last that long. Someone mentioned that part of the reason SolarEdge's warranty is limited to 10 years is primarily based on the cash reserves that they need to offer it.

SolarEdge warranty is 12 years. The below is a link and excerpt from there website.

Single Phase Inverter Feature highlights:

Solar inverters specifically designed to work with power optimizers
Superior efficiency (>97%)
Excellent reliability with standard 12 year warranty (extendable to 20 or 25 years)

http://www.solaredge.us/groups/us/inverter/single-phase-solar-inverter

[thejq]

There are ways money can be put to work that do not incur income taxes or get penalized by inflation. If a panel upgrade was absolutely certain 5 years from now, I would think harder about this. If there is any optionality to it (and in my experience, 5 years is a long time to look ahead and think *anything* is certain), I wouldn't do it. I respect your opinion and I think it is great that subdriver97 is getting opposing points of view to consider. Whatever is decided, it is clear that it will be well thought out, which is as much as any of us can strive for, I think.

Agreed. Opposing but constructive opinions are what people come here for.

[JBinCBad]

Another simpleton Question, can someone explain how to arrive at the cost/watt? Ie, I see people quoting a system cost of $3.5x/watt. Eg, on a 4.5kW system, you just divide the 4,500w by the total cost of the system? So a 4.5kW system costing $15k would be $3.33/watt?

Thanx,
Joel

[thejq]

Another simpleton Question, can someone explain how to arrive at the cost/watt? Ie, I see people quoting a system cost of $3.5x/watt. Eg, on a 4.5kW system, you just divide the 4,500w by the total cost of the system? So a 4.5kW system costing $15k would be $3.33/watt?

Thanx,
Joel

That's right. Simple.

[J.P.M.]

Another simpleton Question, can someone explain how to arrive at the cost/watt? Ie, I see people quoting a system cost of $3.5x/watt. Eg, on a 4.5kW system, you just divide the 4,500w by the total cost of the system? So a 4.5kW system costing $15k would be $3.33/watt?

Thanx,
Joel

Not a simpleton question. Your math/method is correct. $15,000/4,500 Watts = $3.33/Watt. Use nameplate (D.C.) Watts and the price paid to the vendor before any tax credits or rebates.

[JBinCBad]

Thanks guys, I'm learning. Still haven't satisfied myself on where stand on the microinverter vs. SE string inverter choice, but I'm evolving accordingly, and learning a lot from this forum/thread.

Anyone know if the CSI rebate is officially gone for good, or might it resurrect in 2015? (Sorry to highjack OP's thread, btw. . .)

[J.P.M.]

Thanks guys, I'm learning. Still haven't satisfied myself on where stand on the microinverter vs. SE string inverter choice, but I'm evolving accordingly, and learning a lot from this forum/thread.

Anyone know if the CSI rebate is officially gone for good, or might it resurrect in 2015? (Sorry to highjack OP's thread, btw. . .)

No plans for revival at this time.

[MSG]

Hello everyone.

Thanks for all the great info on this forum. I've been soaking up as much as I can and really appreciate the discussion.

Subdriver, would you be willing to PM me your source for your system? Seems like a good place to get started.

Don't want to threadjack but can anyone tell me if:

1) These companies would also do commercial installations?

2) I should expect to pay the same price for commercial vs home?

I assume the answer to both would be yes but I'm not sure if there are differences (regulatory, market premium?) that might change the equation.

Thanks again for your help.

Mike

[MSG]

Thank you jq for your response.