Install in San Diego questions

[bmms8]

Hello, i am a resident of San Diego and a new member of this forum. Ive been able to research and collect good information, so thank you all!

I average about $220 with SDGE and have received multiple quotes on a 5.7-6 kw unit system. Im looking at LG 315 (19.2% efficiency) or 330 watt (19.3% efficiency) panels and a solar edge 6000 or 7600 inverter. Im getting quotes from reputable local installers. Some use hook type installation and some use double flashing. I have no shady area on my roof and the unit will be installed on two south facing portions of the roof. Im also trying to make sure i get a 25 year workmanship warranty for those companies who offer it, along with 20 years on inverter.

Im basically getting between $3-3.10 per watt cost for the system before rebates. Does this seem reasonable or can i talk these guys down even further? If you recommend i look at other brands of panels i am open to all suggestions. Thanks so much in advance

[J.P.M.]

1.) Welcome to the neighborhood.
2.) Suggestion: If you haven't done so already, download and read " Solar Power Your Home for Dummies", free on the net or ~ 25$ at bookstores or Amazon for an updated version. You're thinking of spending $12-$13 K after tax credit. Spending a few bucks and a couple of hours reading, particularly about the better ROI and system size reductions (less$$) possible via conservation and use reduction efforts may be a good investment.
3.) Expect about 9,500 to 10,500 or so kWh/yr. from a 5.7 - 6 kW system in/around San Diego.
4.) I'd use double flashing. Other methods are acceptable including hook types. Double flashing has been around a long time and has seemed to prove its durability, and the post height can be varied to allow more space between roof and panels. That greater height will improve air circulation under the array, lowering panel temps, thus improving efficiency a bit and perhaps lowering panel deterioration some.
5.) Warranties are nice, and everything is negotiable, but I wouldn't kill a deal over them.
6.) The price seems about right as long as you use an established and quality vendor. Go with established local electrical contractors who've been around for at least 10 years and sold solar for at least 5. They'll probably have a better chance of being around in the future. Just don't squeeze the vendor so hard they feel a need or justified to cut corners in ways you're unaware of and will never know about until things go wrong. You're after most long term bang for the buck, not necessarily low buck. There is a difference.
7.) Avoid the big national outfits.
8.) Beyond some basic level of quality, most well known panels are about equal in terms of performance. Some minor quality differences may exist, but if not abused, most panels will prove fit for purpose.

[bmms8]

1.) Welcome to the neighborhood.
2.) Suggestion: If you haven't done so already, download and read " Solar Power Your Home for Dummies", free on the net or ~ 25$ at bookstores or Amazon for an updated version. You're thinking of spending $12-$13 K after tax credit. Spending a few bucks and a couple of hours reading, particularly about the better ROI and system size reductions (less$$) possible via conservation and use reduction efforts may be a good investment.
3.) Expect about 9,500 to 10,500 or so kWh/yr. from a 5.7 - 6 kW system in/around San Diego.
4.) I'd use double flashing. Other methods are acceptable including hook types. Double flashing has been around a long time and has seemed to prove its durability, and the post height can be varied to allow more space between roof and panels. That greater height will improve air circulation under the array, lowering panel temps, thus improving efficiency a bit and perhaps lowering panel deterioration some.
5.) Warranties are nice, and everything is negotiable, but I wouldn't kill a deal over them.
6.) The price seems about right as long as you use an established and quality vendor. Go with established local electrical contractors who've been around for at least 10 years and sold solar for at least 5. They'll probably have a better chance of being around in the future. Just don't squeeze the vendor so hard they feel a need or justified to cut corners in ways you're unaware of and will never know about until things go wrong. You're after most long term bang for the buck, not necessarily low buck. There is a difference.
7.) Avoid the big national outfits.
8.) Beyond some basic level of quality, most well known panels are about equal in terms of performance. Some minor quality differences may exist, but if not abused, most panels will prove fit for purpose.

JPM - thanks for the very informative post!

I will take your advice and be sure to do the above. As of now i am leaning towards Baker as many have done on the forum.

As a side note - will they find the optimal height and angle for the panels on the roof or should i calculate all that and be sure they follow? I don't want to miscalculate but I'm sure i can figure it out with some time. Thanks!

[sensij]

As a side note - will they find the optimal height and angle for the panels on the roof or should i calculate all that and be sure they follow? I don't want to miscalculate but I'm sure i can figure it out with some time. Thanks!

The most cost-effective approach is generally to mount the panels parallel to the plane of the roof, ideally on a south or south-west facing roof. Trying to optimize the orientation further than that is usually more expensive than just adding a panel or two to make up the production difference of the sub-optimal orientation.

[J.P.M.]

JPM - thanks for the very informative post!

I will take your advice and be sure to do the above. As of now i am leaning towards Baker as many have done on the forum.

As a side note - will they find the optimal height and angle for the panels on the roof or should i calculate all that and be sure they follow? I don't want to miscalculate but I'm sure i can figure it out with some time. Thanks!

I have experience w/ Baker from being the HOA guy that reviews/recommends homeowner PV systems for the Arch. rev. Comm., I've seen the good, bad and the ugly. Baker is, IMO, one of the good. I wanted them to do my install, but they were high on price and hard to negotiate with. But, IMO, they are capable of quality, fit for purpose work.

You're welcome. Take your time. This is not a race. Self education will pay big dividends.

As to orientation, you'll probably get stuck with what you have for roof orientations, but do your own investigations. PVWatts will be helpful. See below.

While Baker and others will do arrays that are non parallel to a roof surface, unless you've got a very unusual situation, doing so will probably cost you a lot more $$ than it's probably worth in terms of gains in annual output.

FWIW, optimum orientation to maximize annual output around here on a tiered tariff is ~ 185-195 deg. azimuth, optimum tilt is ~ 28-32 deg. , +/- a few deg. A better orientation for current T.O.U. tariff hours and rates is a bit harder to nail down, but an azimuth of ~ 200-220 deg. and a ~ 30 deg. tilt seems close to optimum for many energy use patterns. Contrary to what some folks think, for T.O.U. residential tariffs, at this time, a 270 deg. azimuth is not as cost effective as a 180 deg. azimuth in terms of offsetting an electric bill. If I had a dichotomous choice of either 180 or 270 deg. azimuth, and if I was on T.O.U, I'd choose 180 deg.

Another suggestion: Get familiar w/PVWatts after you read the book. depending on where you are, see the map w/ PVWatts and get the TMY file location closest to you of the four around the area. Read all the help/info screens a couple of times and try some runs using a 10 % system loss parameter rather than the 14 % default, and get close on tilt/azimuth. You'll probably get pretty close to what you can expect for a long term average annual output.

Don't be surprised if some/most vendors low ball the expected output. Not to bad mouth them out of hand, but they make money putting panels on your property, not getting you the most cost effective size. Estimating your output yourself helps you know what size will have the best probability of meeting your long term output goals. Relying on someone w/ skin in the game is letting the fox guard the henhouse. Just something to keep in mind.

Good luck.

[bmms8]

Thank you to you both i appreciate your inputs!! As i get further along i will update the thread

[bmms8]

I also wanted to note that most installers quoted me for a 5.7 kw system but one major player offered a 4.4 kw system.

My average is about 734 kw per month and they quoted after solar install:

594 kWh per Month
81% Electrical usage offset
105% Electric Bill offset

Does this seem correct? Thanks

[ButchDeal]

I also wanted to note that most installers quoted me for a 5.7 kw system but one major player offered a 4.4 kw system.

My average is about 734 kw per month and they quoted after solar install:

594 kWh per Month
81% Electrical usage offset
105% Electric Bill offset

Does this seem correct? Thanks

possibly with some incentives you can get more funds for say SRECs. They might be counting those funds toward your electric bill.

[SunEagle]

I also wanted to note that most installers quoted me for a 5.7 kw system but one major player offered a 4.4 kw system.

My average is about 734 kw per month and they quoted after solar install:

594 kWh per Month
81% Electrical usage offset
105% Electric Bill offset

Does this seem correct? Thanks

I am not sure of their math. How can you offset your electric bill by 105% yet only offset your electrical usage (due to solar) by 81%?

[J.P.M.]

possibly with some incentives you can get more funds for say SRECs. They might be counting those funds toward your electric bill.

There's o SREC's in CA.

[J.P.M.]

I am not sure of their math. How can you offset your electric bill by 105% yet only offset your electrical usage (due to solar) by 81%?

It's possible, but more details are needed.

[SunEagle]

It's possible, but more details are needed.

It might work for some months but I do not see how it can work all year long. Doesn't the POCO have a minimum meter charge?

[ButchDeal]

There's o SREC's in CA.

sorry didn't realize it was CA.
we don't like to do this even in the east though we do count the SRECs towards payback but not the bill as they are too variable.

[sensij]

I am not sure of their math. How can you offset your electric bill by 105% yet only offset your electrical usage (due to solar) by 81%?

TOU plans. I don't know how they get 105%, but getting all of dollars offset (except for the minimum bill, and non-bypassable charges for imported energy) can be accomplished with a 60%-80% energy offset system, depending on consumption patterns.

[SunEagle]

TOU plans. I don't know how they get 105%, but getting all of dollars offset (except for the minimum bill, and non-bypassable charges for imported energy) can be accomplished with a 60%-80% energy offset system, depending on consumption patterns.

Ok. I guess it could come out that way. Since I do not have a TOU plan it is a little hard for me to do the math.