Final Quotes, need guidance

[nomorecoal]

Hello All,
I have the following quotes and would appreciate guidance for choosing them.

Location: Maryland
Requirement:

• Prefer black frame, since the panels will be on the front side roof of my house
• Maximize output at lower (not necessarily lowest) price

Item	Option 1	Option 2	Option 3
Panel	Solar World SW-315-XL-Mono	Silveo Triex-U300-black	SunPower SPR-E20-327
Watt (STC/PTC)	315 / 275.6	300 / 281.5	327 / 301.4
Inverter	1 X Solar Edge SE 7600A-US (240v)	1 X Solar Edge SE 7600A-US (240v)	2 X SunPower SPRm-TL w/ SPS
# of Panels	25	27	22
Output (DC)	7,875	8,100	7,194
Annual output (according to PVWatts)	10,674	10,983	9,753
Price per DC watt	$3.17	$3.31	$4.05

Few SunPower panels are listed because that's all I could afford.

I am leaning towards option 2 as it provides me

1. A black panel
2. Better warranty (Like SunPower, Silveo offers free pickup and shipping for defective panel) and
3. Higher output to offset my utility provider’s cost

I also believe that the true output from option 2 would be higher than PVWatts because of its higher PTC watts, which somehow is not factored in by PVWatts.

What is your recommendation and does anyone have experience with Silveo panel?

I appreciate your help.

[JCP]

Hello All,
I have the following quotes and would appreciate guidance for choosing them.

Location: Maryland
Requirement:

• Prefer black frame, since the panels will be on the front side roof of my house
• Maximize output at lower (not necessarily lowest) price

Item	Option 1	Option 2	Option 3
Panel	Solar World SW-315-XL-Mono	Silveo Triex-U300-black	SunPower SPR-E20-327
Watt (STC/PTC)	315 / 275.6	300 / 281.5	327 / 301.4
Inverter	1 X Solar Edge SE 7600A-US (240v)	1 X Solar Edge SE 7600A-US (240v)	2 X SunPower SPRm-TL w/ SPS
# of Panels	25	27	22
Output (DC)	7,875	8,100	7,194
Annual output (according to PVWatts)	10,674	10,983	9,753
Price per DC watt	$3.17	$3.31	$4.05

Few SunPower panels are listed because that's all I could afford.

I am leaning towards option 2 as it provides me

1. A black panel
2. Better warranty (Like SunPower, Silveo offers free pickup and shipping for defective panel) and
3. Higher output to offset my utility provider’s cost

I also believe that the true output from option 2 would be higher than PVWatts because of its higher PTC watts, which somehow is not factored in by PVWatts.

What is your recommendation and does anyone have experience with Silveo panel?

I appreciate your help.

I'd with #1, or maybe add a 26th panel to get a bigger production.

[J.P.M.]

Before you pull the trigger, try the same input using the new PVWatts - 3 days old.

The results may be a bit different due to the premium and standard options.

Reason: Output/nameplate Watt is the same for all 3 under the old PVWatts. Also, depending on the derate factor you used on the old PVWatts, things might change a bit as well. If new PVWatts output estimate is substantially higher you may want to revisit sizing for optimum cost effectiveness.

However, seeing as how this is all an estimate of long term performance and probably no better than +/- 10% or so for any given year, output among the 3 is probably going to be close.

Given that, it looks like a matter of balancing confidence in the vendor and personal product preference with respect to quality and aesthetics against cost.

Read all the fine print, believe nothing that's not written down and Caveat Emptor. Then, take your best shot, pay your money and take your choice.

[nomorecoal]

The published numbers are base on the new PVWatts site.
Tilt: 32
Azimuth: 185

I selected standard for Solar World and Silevo whereas premium for Sun Power.

Besides aesthetics, should attach premium to things like warranty and weight of the panels as they favor Silevo?

[J.P.M.]

The published numbers are base on the new PVWatts site.
Tilt: 32
Azimuth: 185

I selected standard for Solar World and Silevo whereas premium for Sun Power.

Besides aesthetics, should attach premium to things like warranty and weight of the panels as they favor Silevo?

Question: How did the outputs chance with the new PVWatts vs. the old one ?

Only you can decide what's best for you.

I'd spend some time evaluating my feeling about installers. A good one is worth a slight premium. That's a gut call, but this is more than just a bottom line dollar decision. A good installer is cheap insurance.

Get your roof inspected/serviced. More cheap insurance you won't regret. Trust me on that one.

I'm unfamiliar w/Silevo. That does not mean bad, just that I'm ignorant as to their quality.

IMO, the S.P. warranty is oversold and overkill. I can gamble for the ~ $3,500 savings after tax credit for the more cost effective panels on the philosophy that fortune favors the bold. But again, that's only my opinion and matters not. What matters right now is yours, and yours is the only opinion that counts.

Good Luck.

[nomorecoal]

The newer PVWatts generated a higher output compared to the older one (even with derate of .84).

My house is just 4 yrs old so it doesn't need inspection.
The installer is offering 5 yr warranty on workmanship and performance guarantee.

So while I have selected the installer, the choice of panel is confusing me.

I looked at LG as well, but their 300 watt panels are almost $1.34 per watt, compared to $1.09 for Silevo and $0.95 for SolarWorld. However, once I factor in annual production, because I can afford more Silevo panels that have higher PTC, the per unit price difference goes down further.

The way I am calculating per kWh hour is
net price (after incentives) divided by Total production over 20 yrs based on 97% for first year and annual loss of 0.7%

So for instance, if annual production is 10,983 kWh then I multiple it by 18.3 to arrive at 200,988 kWh over 20 yrs.

Divide net cost say, $18,000 by 200,988; then I get $0.0896 kWh which gives me an idea as to what panel would cost effective in the long run.

I am ignoring SRECs because (A) they are hard to predict and (B) the earned amount would pay for higher property tax, homeowners insurance and any maintenance.

[J.P.M.]

The newer PVWatts generated a higher output compared to the older one (even with derate of .84).

My house is just 4 yrs old so it doesn't need inspection.
The installer is offering 5 yr warranty on workmanship and performance guarantee.

So while I have selected the installer, the choice of panel is confusing me.

I looked at LG as well, but their 300 watt panels are almost $1.34 per watt, compared to $1.09 for Silevo and $0.95 for SolarWorld. However, once I factor in annual production, because I can afford more Silevo panels that have higher PTC, the per unit price difference goes down further.

The way I am calculating per kWh hour is
net price (after incentives) divided by Total production over 20 yrs based on 97% for first year and annual loss of 0.7%

So for instance, if annual production is 10,983 kWh then I multiple it by 18.3 to arrive at 200,988 kWh over 20 yrs.

Divide net cost say, $18,000 by 200,988; then I get $0.0896 kWh which gives me an idea as to what panel would cost effective in the long run.

I am ignoring SRECs because (A) they are hard to predict and (B) the earned amount would pay for higher property tax, homeowners insurance and any maintenance.

I'd do the cost analysis and the cumulative output different, but that matters not - it's your money, your choice.

[nomorecoal]

How would you recommend.

I also tried to SAM, but it doesn't have SW-315-XL panel listed.

Also, the annual output of Silevo is 11,010 kWh; which is slightly higher than PVWatts website. The return on investment is also quicker.

Are they any tools available to calculate ROI?

[prhamilton]

Paying 5% more for something because of aesthetics is not unreasonable. I don't want to tell you how much more we spent on a fridge because we liked the way it looked.

All three are solid panels, the installer is going to have a much bigger impact on the reliability of the system than one of these panels over another. I think was said earlier but if you have the room you might consider an extra panel or two.

[russ]

I'd do the cost analysis and the cumulative output different, but that matters not - it's your money, your choice.

Agreed - the magic to come up with 200,998 is cute.

[prhamilton]

Agreed - the magic to come up with 200,998 is cute.

Enlighten us, how would you do it? I think it's a reasonable back-of-the-envelope estimate of cumulative production.

[J.P.M.]

Enlighten us, how would you do it? I think it's a reasonable back-of-the-envelope estimate of cumulative production.

Perhaps as a dart throw for cumulative production but I thought the OP was wondering about ROI.

In the eyes and mind of a lot of people informed on the subject - use something called process economics or life cycle cost analysis. A somewhat easier way to get a meaningful # that uses a lot of that same stuff is to use SAM and plug in the financial stuff. Output will be LCOE (Levelized Cost Of Energy) which is some of what a life cycle cost analysis yields and usually closer to what most folks are after from the cost effective side of requirements but don't know it.

[J.P.M.]

How would you recommend.

I also tried to SAM, but it doesn't have SW-315-XL panel listed.

Also, the annual output of Silevo is 11,010 kWh; which is slightly higher than PVWatts website. The return on investment is also quicker.

Are they any tools available to calculate ROI?

Sometimes SAM takes a while to catch up. Send them an e-mail and they may be able to advise when that panel will be available.

If you're referring to the diff. in est. output between SAM and PVWatts - minor diff. in output are often the result of small changes or differences in input parameters. SAM is also more sophisticated than PVWatts.

I'm sure there is software available for financial calculations, but, depending on the level of sophistication sought, unless you are familiar with the a few basics like the time value of money and compound interest and a few other things, that can be the financial equivalent of giving a loaded pistol to a 2 yr. old.

[Quinten]

I just had a 11kw system installed with 40 sunworld 275w panels and a solaredge se11400a-us inverter. I was going to go with the sunpower system, but didn't want the SMA inverters. I thought shade wouldn't be an issue, and it probably isn't too much, but I noticed that two of the panels on the south facing array get some shade from the roof later in the day and the voltage dropped down quite a bit on those two panels while total output wasn't terribly affected. Not sure how the SMA inverters would handle the shade (not as well I'm sure), but I'm quite happy with the solarworld/solaredge system. I've been getting ~ 62 KWh a day over the past week. Had two semi cloudy days and the output dropped to about ~ 55 KWh which was higher than I anticipated as the panel voltage would drop under 1kw at times. The highest output I've seen is ~8.5 kw... have to wait until next June to see what the high will be

[control4userguy]

I don't have much experience here- is 77% (8,500/11,000) conversion rate acceptable?