Hello from Missouri City, Texas (SW Houston)

[Ampster]

In California, I recently self installed a system using additional labor and an electrician who changed out a main service panel and the cost was under $2.50 per Watt. If I back out the labor the material costs were $1.50 per Watt. Labor can't be that much different between Texas and California so the balance may be SunRun overhead and profit. I would also like to see a comparison of other proposals using a per Watt metric. Has SunRun explained that a Grid Tied system will not provide power when the grid is down?

[GoingElectric]

(Really want to load pictures, but keeps giving me error messages)

A National installer
Sys Size 6.15 kWp
Est Ann prod 8000 kWh
15x Hanwa ML-G10+
15x Enphase IQ8+
$18,656

B National installer
Sys Size 5.95 kWp
Est Ann prod 8050 kWh
14x Equinox M 425W
14x micro inverters
$23,240

C Local installer
Sys Size 7.20 kWp
Est Ann prod 10.5 kWh
18x panels
18x micro inverters
$15,664

D Local installer
Sys Size 7.40 kWp
Est Ann prod 10,020 kWh
20x panels
20x micro inverters
$ 13,690

E Local installer
Sys Size 7.65 kWp
Est Ann prod kWh
17x panels
1x inverters
$ 13,020

F Local installer
Sys Size 7.04 kWp
Est Ann prod kWh
16x Panels
16x micro inverters
$ 15,368

G Local installer
Sys Size 8.03 kWp
Est Ann prod kWh
22x panels
1x inverters
$ 16,876

H Local installer
Sys Size 7.03 kWp
Est Ann prod 10,545kWh
19x panels
1x inverters
$ 14,202

(and yes, I notice some suspect items)

[peakbagger]

BTW, what sort of net metering rules do you have from your utility. Texas utilities seem to be quite variable in how they accept solar from various reports I have seen over the years. Is it true net metering where the value of the power sent to the grid is equal to the value of the power being recovered from the grid?. Is there a yearly mandatory true up date where any built up credit is either zeroed out by the utility or paid out at a wholesale rate. If there is true up date when is it relative to the peak production versus peak demand? Any taxes on production?. All of these need research prior to installing a system.

There is and has been an ongoing push by ALEC (sponsored by the Koch's) to roll back net metering laws around the country, some utilities are "solar friendly" but many are not.

[GoingElectric]

BTW, what sort of net metering rules do you have from your utility. Texas utilities seem to be quite variable in how they accept solar from various reports I have seen over the years. Is it true net metering where the value of the power sent to the grid is equal to the value of the power being recovered from the grid?. Is there a yearly mandatory true up date where any built up credit is either zeroed out by the utility or paid out at a wholesale rate. If there is true up date when is it relative to the peak production versus peak demand? Any taxes on production?. All of these need research prior to installing a system.

There is and has been an ongoing push by ALEC (sponsored by the Koch's) to roll back net metering laws around the country, some utilities are "solar friendly" but many are not.

Texas does have more options than others.
https://quickelectricity.com/2018-so...back-programs/

Octopus does buy back, I am inclined to go with them

[GoingElectric]

Good info here on string inverters

[J.P.M.]

Good info here on string inverters

Well, a lot of informed folks around here (including me) for a lot of reasons think string inverters are a better option micros or optimizers.
I'm happy to see you're considering that option. You'll wind up with a simpler and more reliable system. It may even save you a few bucks.

[GoingElectric]

Well, a lot of informed folks around here (including me) for a lot of reasons think string inverters are a better option micros or optimizers.
I'm happy to see you're considering that option. You'll wind up with a simpler and more reliable system. It may even save you a few bucks.

I asked, and one said savings of $600.

I think it was 6 years ago I first asked about PV, and the cost still has not reduced much, if at all...

[J.P.M.]

I asked, and one said savings of $600.

I think it was 6 years ago I first asked about PV, and the cost still has not reduced much, if at all...

The savings are possible and perhaps likely, but that's small potatoes compared to the simplicity and higher probability of more/better system reliability that string inverter systems enable. It's called the KISS principle.

[bcroe]

Good info here

It is interesting to read that they think the inverter is the most failure prone
part of a string system. After 9 years here, the several problems were all
related to wiring failures. The pair of inverters, running in clipping for 8 hours
straight every sunny day, just keep working. Maybe the indoor installation
is really important?

On cost, the 260' wire upgrade I did 2 years ago, has seen the delivered price
of the wire increase from $650, to $1500. Aluminum for the ground arrays is
worse. Bruce Roe

[GoingElectric]

It is interesting to read that they think the inverter is the most failure prone
part of a string system. After 9 years here, the several problems were all
related to wiring failures. The pair of inverters, running in clipping for 8 hours
straight hours every sunny day, just keep working. Maybe the indoor installation
is really important?

On cost, the 260' wire upgrade I did 2 years ago, has seen the delivered price
of the wire increase from $650, to $1500. Aluminum for the ground arrays is
worse. Bruce Roe

That is probably it, Al and Cu parts went up in price while the panels and inverters went down.
Did not factor in the system size and advent of micros that change the price matrix some.

[GoingElectric]

The savings are possible and perhaps likely, but that's small potatoes compared to the simplicity and higher probability of more/better system reliability that string inverter systems enable. It's called the KISS principle.

Yes, because of my roof am leaning to string.

How can one attach photos in this forums?

[J.P.M.]

Yes, because of my roof am leaning to string.

How can one attach photos in this forums?

What are the reasons your roof will affect your equipment choices ?

Using string inverters will decrease - but most likely not eliminate - the probability of increased need to get on the roof, but that would apply to most any roof. Is it the 40 degree slope ?

However, be aware that micros and optimizers usually take care of the need for meeting rapid shutdown requirements many building codes require. String inverters need extra equipment do that. Part of your self education.

As for attachments to a post, I don't know. I've never attached anything to my posts. I'd root around in the help section.

[Ampster]

Attachments are in one of the drop downs at the top of the screen where you compose your posts. You can link or on the image drop down there is a tab to attach a file.

[GoingElectric]

What are the reasons your roof will affect your equipment choices ?

Using string inverters will decrease - but most likely not eliminate - the probability of increased need to get on the roof, but that would apply to most any roof. Is it the 40 degree slope ?

However, be aware that micros and optimizers usually take care of the need for meeting rapid shutdown requirements many building codes require. String inverters need extra equipment do that. Part of your self education.

String reduces failure points and slightly reduce cost, lower potential maintenance.
I do understand the redundancy and gaining max power from each panel instead of a system wide.
Still not make final decision either way.

Rapid shut down,.. that is something I need to ask and not assume from contractor. Thanks.

[bcroe]

I read the claim of an advantage to optimizing the power of each
individual panel. Sure, if you have real issues with shadows. But
in good sun, I propose that any advantage is almost completely in
their imagination. The maximum power point area of a panel is
somewhat broad. Bruce Roe