Solar Purchase vs Lease - Newbie

[Mike90250]

Microinverter: fairly new, in the field about 2 years, and claims for a 15 or 20 year lifetime

Single large inverter: around for 20+ years, repairable, easily replaceable, and about a 10 year lifetime.

So in ten years, I would expect to repair / replace 1 large inverter, that weighs about 90 lb. Or I'd be expecting to have to get on the roof, and change out 3 or 4 of the microinverters, if the vendor is still around.

If I don't have shade issues to solve with microinverters, I would not use them.

[Naptown]

full manufacturer's name and model number for an opinion.
The Schuco's are made by Canadian Solar and private labeled.
Mono's use Sharp cells and assembled by CS
Poly's are pure CS
Don't know anything about the thin films.
Canadian solar and thus the Schuco have the highest PTC ratings of anyone as a ratio of STC to PTC higher PTC = More calif rebate
Their power tolerance is -0% this will help with output.
Not sure who makes to Schuco 03 series this seems to be a new module and made in USA
The phono's are +/- 3%

[csriram45]

Microinverter: fairly new, in the field about 2 years, and claims for a 15 or 20 year lifetime

Single large inverter: around for 20+ years, repairable, easily replaceable, and about a 10 year lifetime.

So in ten years, I would expect to repair / replace 1 large inverter, that weighs about 90 lb. Or I'd be expecting to have to get on the roof, and change out 3 or 4 of the microinverters, if the vendor is still around.

If I don't have shade issues to solve with microinverters, I would not use them.

What about the advantages of microinverter that you can get individual monitoring of panels so even if one is producing less or has become the others continue to produce. Also if I want to add panels in future I am told it's easy to do so etc.

I realize both have advantages and disadvantages. So you are suggesting that the advantages of microinverter do not outweigh those of single inverter?

[Naptown]

Mike and others here do not like micro's
I happen to like them for a number of reasons
1- MPPT tracking on a per module basis as opposed to an entire string.
2- Lower DC wiring losses.
3- In many cases depending on jurisdiction can be a lower install cost even though the inverters themselves are more.
4- Per module monitoring will show problems much faster than the whole system monitoring will and will point the way to where the problem is.
5- Can be added on to easily each parallel string can have 15-20 modules on it
If there are less than that adding on is plug and play.
6- These are somewhat safer in the event of a fire as there will not be live 300-600 volts dc on the roof voltage will be limited to one module open circuit voltage.

Microinverters have been around since the late 70's however the early designs proved to have a poor lifespan and track record and were not produced for a long time. The current generation I strongly believe are much better engineered than the first generation.

There is truth to the statement that they will harvest more electricity than a string inverter. Just eliminating the module mismatch, differences in power tolerance and soiling differences on the modules will generate a greater harvest.

[Mike90250]

new fangled microinverters

[csriram45]

OK. I see its about new design with higher potential vs proven track record.

I got a revised quote from another private installer.

Total System Size 3.290 kW DC Power (STC) / 2.821 kW AC Power (CEC)
Estimated Annual Production 4,789 kWh
PV Panel Description 14 x ET Solar Industry, Ltd. Model: ET-P660235B
Inverters Qty. 14 - Enphase Energy Model: M190-72-240-S02


Gross System Cost $17,000 ($5.17/watt DC, $6.03/watt AC)
CA Expected Perf-Based Buydown (EPBB) Step 8 ($987)
Installer Contract Cost $16,013 ($4.87/watt DC, $5.68/watt AC)
Federal Tax Credit/Tax Impact ($4,804)
Net Cost (year of installation) $11,209 ($3.41/watt DC, $3.97/watt AC)

I seem to have narrowed down to these 2 proposal

What do you guys have to say about this proposal compared to the Schuco proposal below? Both of them are about the same price. Question now would be which is a better panel and set up. One with ET Panel and microinverter and another with Schuco panel with SB inverter. If I knew who does a better job of installing etc. I would have gone with them but I have no idea who does it better.

System Size: 3.29 STC KW PV System
14 Schuco 235 MPE PSO4
1-SB4000US Inverter and integrated AC/DC Disconnect
SUBTOTAL (Labor & Tax included) $ 22,128.94
CEC Incentive $977.00
Installer discount - 24% (more a random #)
TOTAL $16,100.00
Federal Tax Incentive $4,830.00
CUSTOMER EXPECTED COST $ 11,270.00

[Mike90250]

ask both installers for references, and go visit their installs.

also ask about roof leaks, who covers that and for how long. 5 years would be reasonable.

When is your roof due for replacement ? less than 10 years, you may elect to do it now, before the PV, and not worry for 30 years. Maybe you can get the roofer and PV to work together to put good flashing on the mounts.

[csriram45]

My home is very new 2006 so i don't expect it to be replaced any time soon. I do agree I should get the references. Will ask them about roof leaks etc. Thanks for the inputs.

If everything checks out which panel is preferred?

[Mike90250]

If everything checks out which panel is preferred?

I have no experience with either. Which company is more diversified ? That's the one likely to be in business in 10 - 20 years

[csriram45]

I have no experience with either. Which company is more diversified ? That's the one likely to be in business in 10 - 20 years

Not sure. From what I hear both ET and Schuco are made by Canadian Solar . The installer with ET panel told me that he covers leaks up to 10 years and in fact it is required by law.

[Naptown]

new fangled microinverters

Kinda like that new fangled horseless carriage

[Naptown]

They are pretty equal systems. Just to get back at the competition (Not in this case) make the Schuco gut match the Enphase or buy a Canadian solar module for less.

[csriram45]

Interesting turn of events. Real Goods tried to get in touch with me to find out what happened. When I told them that I got competitive quote they are now frantically trying to match it. It does help that I got few others who are interested to go solar and I have told them that depending on how they treat me I can recommend to friends.

RGS is now trying to get me Sharp 235W panel. Any insights on that? How do those compare?

Thx

[Naptown]

Interesting turn of events. Real Goods tried to get in touch with me to find out what happened. When I told them that I got competitive quote they are now frantically trying to match it. It does help that I got few others who are interested to go solar and I have told them that depending on how they treat me I can recommend to friends.

RGS is now trying to get me Sharp 235W panel. Any insights on that? How do those compare?

Thx

similar quality to check PTC output go to gosolarcalifornia.org and check the ptc ratings on the different modules.

[csriram45]

Yeah I did check the ratings. Thx. Yet to get the RGS proposal as they are working the #s. lets see how it goes.

BTW, will AB 920 etc people who eventually consume more than what they generate? I wonder if utilities have to pay higher price for what you generate because it is generated by a greener method than what they sell to you which is by traditional method? This means I would have negative bill because even though I consume more but what I generate is sold to PGE at higher cost. A hopeful and wishful thinking but with Gov. Brown signing a bill that 30% of CA electricity should be from green sources it would mean utilities are dependent on us.