Solar system help need (Northern California - Bay area)

[foo1bar]

Questions:
1. How are the quotes above?
2. Is the consumption monitoring recommended? Some of the installers suggesting using Sense to do the consumption monitoring
3. Which inverter is recommended for these systems? I am more favorable to Enphase or Solaredge
4. Rack/Mount - Unirac or Ironridge?

If anyone is from the bay area please feel free to message me your learning as well thank you.

You didn't say which part of the bay area.
I live in the south bay and have two vendors you should probably look at if you haven't already.
1> Suns Up Solar from Santa Cruz. (they were the subcontractor for an install I handled as the "owner" - a church install)
2> SunWork in Milpitas (They're a non-profit, and only do small systems (less than $100 electric bill). They may be a good fit for you if you're willing/able to work up on your own roof.)

[ccjw33]

You didn't say which part of the bay area.
I live in the south bay and have two vendors you should probably look at if you haven't already.
1> Suns Up Solar from Santa Cruz. (they were the subcontractor for an install I handled as the "owner" - a church install)
2> SunWork in Milpitas (They're a non-profit, and only do small systems (less than $100 electric bill). They may be a good fit for you if you're willing/able to work up on your own roof.)

Hi South bay too. I did check with Sunwork but they only offer 10 years workmanship so that's my concern mainly. For Suns up solar I didn't check but I will look them up thank you. Any idea what's the reasonable rate for these 2 companies? I don't believe Sunwork is negotiable but not sure about Sun Up Solar.

[foo1bar]

I don't believe Sunwork is negotiable but not sure about Sun Up Solar.

I don't know...
It looks like you're going for ~4.5kW. The project that I had SunsUp as the subcontractor was 57kW (so economies of scale, etc. means it should be cheaper than a small project like yours)
But the contract was signed >2.5 years ago, and there was a middle-man (so price could be cheaper because of those factors)

3 years ago I think $3/W was doing pretty good for a contractor-installed system in the ~9kw range.
Maybe with 3 years of time you can get $2.75/W like I had on that large install, but on your tiny install. Maybe not.
Do you have a composite shingle roof? (tile may cost extra)
Do you have a walk-able roof (not overly steep)?
Do you have an easy route from the roof to where the inverter will sit?
Do you have an easy route from the inverter to your main breaker panel?
Will you need a main panel upgrade/replacement?
BTW - if you have a Zinsco or Federal Pacific panel, I'd upgrade the panel at the same time as your solar install. Talk to your tax guy, but probably it could be lumped in as a necessary thing for your solar installation and therefore counts for the 30% credit. (That it gets rid of that hazardous panel is good for resale value too)
Is now a good excuse to upgrade your electrical service as well and get tax credit on that too?
Lots of questions that really can affect what price is reasonable for your solar installation.

[foo1bar]

BTW - I'd probably look at doing a larger system. My home install (DIY install) was sized for my usage at the time - but then I bought an PHEV which is mostly being used as an EV.
Although if you're PG&E the time of use rates might not make it worthwhile. (I'm Silicon Valley Power but have friends in PG&E territory - and they generate fewer kwh per year than they use, but they have enough kwh during off-peak that it is more more than paid for by the generation during peak hours)

[ccjw33]

I don't know...
It looks like you're going for ~4.5kW. The project that I had SunsUp as the subcontractor was 57kW (so economies of scale, etc. means it should be cheaper than a small project like yours)
But the contract was signed >2.5 years ago, and there was a middle-man (so price could be cheaper because of those factors)

3 years ago I think $3/W was doing pretty good for a contractor-installed system in the ~9kw range.
Maybe with 3 years of time you can get $2.75/W like I had on that large install, but on your tiny install. Maybe not.
Do you have a composite shingle roof? (tile may cost extra)
Do you have a walk-able roof (not overly steep)?
Do you have an easy route from the roof to where the inverter will sit?
Do you have an easy route from the inverter to your main breaker panel?
Will you need a main panel upgrade/replacement?
BTW - if you have a Zinsco or Federal Pacific panel, I'd upgrade the panel at the same time as your solar install. Talk to your tax guy, but probably it could be lumped in as a necessary thing for your solar installation and therefore counts for the 30% credit. (That it gets rid of that hazardous panel is good for resale value too)
Is now a good excuse to upgrade your electrical service as well and get tax credit on that too?
Lots of questions that really can affect what price is reasonable for your solar installation.

Do you have a composite shingle roof? Yes
Do you have a walk-able roof (not overly steep)? Yes not deep
Do you have an easy route from the roof to where the inverter will sit? Yes
Do you have an easy route from the inverter to your main breaker panel? Yes
Will you need a main panel upgrade/replacement? No just upgraded less than a year ago to 200amp

I have already bump up my usage by 15% from the last year total and also adding EV charging so I believe around 4.6 up and down will do the job for my house in the next 10-20 years. So far I feel like only LG335w will get to $3/w unless I go through company like Sunwork where they might do it for slightly cheaper but they will only cover 10 years workmanship instead of 20 or 25 years from other installers.

[JSchnee21]

IMHO, 10yr workmanship is fine. Most solar installers go out of business in 5yrs or less making a lot of workmanship "warranties" worthless. If it were me, I would buy an extended warranty from Solar Edge for the inverter to upgrade to 25yrs to match the Optimizers which come with 25. The panels will be 10, 12, or 25 yrs depending on which ones you get. Realistically speaking, after 10 yrs or so it's more likely you have moved or replacement hardware will be the same price as the extended warranty is now. For example, an 11.2kW SE inverter is only $2000 new. The extended warranty from 10-25 was ~$450 or so. Is that really worth it? Will SE be in business in 10 or 15 years? I have no idea. Panels are only $250-400 each. If one or two fail after 10 or 15 years and you have to replace them is that really such a big deal?

[ccjw33]

IMHO, 10yr workmanship is fine. Most solar installers go out of business in 5yrs or less making a lot of workmanship "warranties" worthless. If it were me, I would buy an extended warranty from Solar Edge for the inverter to upgrade to 25yrs to match the Optimizers which come with 25. The panels will be 10, 12, or 25 yrs depending on which ones you get. Realistically speaking, after 10 yrs or so it's more likely you have moved or replacement hardware will be the same price as the extended warranty is now. For example, an 11.2kW SE inverter is only $2000 new. The extended warranty from 10-25 was ~$450 or so. Is that really worth it? Will SE be in business in 10 or 15 years? I have no idea. Panels are only $250-400 each. If one or two fail after 10 or 15 years and you have to replace them is that really such a big deal?

Hi Jschnee21, quick question. Do you know if LG 335w panels will work with IQ7 without clipping? I was told by some installers that the IQ7+ is preferred since IQ7 will not be able to handle at peak time. I also see Enphase recommended IQ6+ in the past which makes me think the IQ7+ might works better with LG 335w panels thank you.

[JSchnee21]

Hi ccjw33 ,

First, let me say that I'm not an expert on Enphase equipment. But based on the LG spec sheet for the LG335N1C-A5, Enphase's spec sheet for the IQ7/7+, and the Enphase module compatibility tool most Enphase Micros are "compatible" with the LG335. But, in order to limit clipping the IQ6+ or IQ7+ would be preferred due to their higher output VA capability.

Now, the question is how much clipping would there realistically be. Let's take the IQ7 series for example.

The IQ7 max output is 250VA (240VA continuous), while the IQ7+ max output is 295VA (290VA continuous). The LG335W @STC is 335W. But in the real world, it's pretty rare for panels to put nameplate (STC) power levels, and when they do, it is typically only for brief periods of time. The NOCT for the LG335 is only 247W, so in reality, unless you live in a cool, clear very sunny location it's fairly rare that your panels would be producing much more than ~250-300W for any significant period of time.

For comparison, I have Panasonic 330W panels at 175 degrees azimuth (good) and 20 degree inclination (not so good) at a latitude of 40.38 degrees here in NJ. It's very rare for my panels to put out more than 260-290W. But, I see at least 220-270W most days during peak sun from ~11 to 1. Today actually, it was very sunny and cold (~25F) and there was still some glare from a previous snow fall and I was up in the 290-310W range from ~11:15 to ~12:45. But as the weather warms into the Spring and Summer peak wattage per panel falls (due to increased temperatures) despite a significant increase in sun hours per day. I think I can count on one hand the number of times my panels sustained 330W for more than a few seconds at a time.

There will potentially be some clipping with the IQ7 (e.g. when solar irradiance is greater than 800W/square meter and temperatures are cooler), and occasionally even some with the IQ7+ (e.g. Southern California -- like LA where my brother-in-law lives -- is especially bright). But clipping is really only a "problem" (e.g. significant lost production) if it lasts more than 30 to 60min per day, at least 25% of days per month, multiple months of the year. But the amount/duration of the clipping will depend on the orientation and tilt of your array, the typical solar irradiation in your location, and the temperature.

What is the cost differential/availability of the IQ7+ versus the IQ7? I.E. why not just get the IQ7+? Or better still get a SolarEdge system which will have no clipping (assuming you have a large enough central inverter)

At Renvu for example, in quantities from 1 to 35. The cost of the three Micros is very similar
IQ6+ $129.95
IQ7 $123.63
IQ7+ $136.85

-Jonathan

[ccjw33]

Hi ccjw33 ,

First, let me say that I'm not an expert on Enphase equipment. But based on the LG spec sheet for the LG335N1C-A5, Enphase's spec sheet for the IQ7/7+, and the Enphase module compatibility tool most Enphase Micros are "compatible" with the LG335. But, in order to limit clipping the IQ6+ or IQ7+ would be preferred due to their higher output VA capability.

Now, the question is how much clipping would there realistically be. Let's take the IQ7 series for example.

The IQ7 max output is 250VA (240VA continuous), while the IQ7+ max output is 295VA (290VA continuous). The LG335W @STC is 335W. But in the real world, it's pretty rare for panels to put nameplate (STC) power levels, and when they do, it is typically only for brief periods of time. The NOCT for the LG335 is only 247W, so in reality, unless you live in a cool, clear very sunny location it's fairly rare that your panels would be producing much more than ~250-300W for any significant period of time.

For comparison, I have Panasonic 330W panels at 175 degrees azimuth (good) and 20 degree inclination (not so good) at a latitude of 40.38 degrees here in NJ. It's very rare for my panels to put out more than 260-290W. But, I see at least 220-270W most days during peak sun from ~11 to 1. Today actually, it was very sunny and cold (~25F) and there was still some glare from a previous snow fall and I was up in the 290-310W range from ~11:15 to ~12:45. But as the weather warms into the Spring and Summer peak wattage per panel falls (due to increased temperatures) despite a significant increase in sun hours per day. I think I can count on one hand the number of times my panels sustained 330W for more than a few seconds at a time.

There will potentially be some clipping with the IQ7 (e.g. when solar irradiance is greater than 800W/square meter and temperatures are cooler), and occasionally even some with the IQ7+ (e.g. Southern California -- like LA where my brother-in-law lives -- is especially bright). But clipping is really only a "problem" (e.g. significant lost production) if it lasts more than 30 to 60min per day, at least 25% of days per month, multiple months of the year. But the amount/duration of the clipping will depend on the orientation and tilt of your array, the typical solar irradiation in your location, and the temperature.

What is the cost differential/availability of the IQ7+ versus the IQ7? I.E. why not just get the IQ7+? Or better still get a SolarEdge system which will have no clipping (assuming you have a large enough central inverter)

At Renvu for example, in quantities from 1 to 35. The cost of the three Micros is very similar
IQ6+ $129.95
IQ7 $123.63
IQ7+ $136.85

-Jonathan

Thanks Jonathan. I agree with you 100% and also checked Renvu's engineer and they also recommend IQ7+. Enphase website also can check compatibility and they also recommended IQ6+ with Neo 2 or above panels in the past which IQ7+ is the replacement of IQ6+. Thanks again.

[ccjw33]

BTW - I'd probably look at doing a larger system. My home install (DIY install) was sized for my usage at the time - but then I bought an PHEV which is mostly being used as an EV.
Although if you're PG&E the time of use rates might not make it worthwhile. (I'm Silicon Valley Power but have friends in PG&E territory - and they generate fewer kwh per year than they use, but they have enough kwh during off-peak that it is more more than paid for by the generation during peak hours)

Hi foo1bar, I did receive the quote from Sunwork for the 4.69kw LG system with enphase inverter for 2.68/w but they have been recommend for REC-315-TP2M or REC-320-NP system which uses same converter for $2.47/w. I also got LG 335 and 340w panels with enphase from others installer and the lowest is $2.89/w. Main difference between Sunwork and other installers are 25 years vs 10 years workmanship and warranty. With the system I am doing we are talking about $1,750 saving for 15 years less workmanship. What do you think? I know you mentioned any installer can goes out of the business and I also feel that's the risk too so like to get your opinion thank you.

[JSchnee21]

Hi ccjw33,

One other thing to keep in mind. Historically, Enphase Micros have a nasty habit of failing and needing to be replaced. While the newer models (post m215/m250) seem to be better, over the last 4 years or so Enphase has been coming out with a new model almost every year. This has made it difficult to keep track of which model revisions are working well and which ones aren't. And there hasn't been a lot of info / comments one way or the other on the newer models (S-series, IQ6-series, IQ-series).

So what I'm getting it is which every installer you choose, be sure their warranty includes the labor coverage to remove the effected panel and replace the Micro when/if it fails. Regardless of the warranty duration (10 or 25) or price, I would try (I know this is difficult) to choose the installer which is more likely to still be in business in 5 or 10yrs when components may begin to fail. Sometimes it can be difficult to find another installer who will service an existing system which they did not install themselves. Of course install quality matters, too.

All the best,
Jonathan

[solar pete]

Hi ccjw33,

One other thing to keep in mind. Historically, Enphase Micros have a nasty habit of failing and needing to be replaced. While the newer models (post m215/m250) seem to be better, over the last 4 years or so Enphase has been coming out with a new model almost every year. This has made it difficult to keep track of which model revisions are working well and which ones aren't. And there hasn't been a lot of info / comments one way or the other on the newer models (S-series, IQ6-series, IQ-series).

So what I'm getting it is which every installer you choose, be sure their warranty includes the labor coverage to remove the effected panel and replace the Micro when/if it fails. Regardless of the warranty duration (10 or 25) or price, I would try (I know this is difficult) to choose the installer which is more likely to still be in business in 5 or 10yrs when components may begin to fail. Sometimes it can be difficult to find another installer who will service an existing system which they did not install themselves. Of course install quality matters, too.

All the best,
Jonathan

Well said sir, call me cynical but I believe the reason for discouraging panel level monitoring by making it some thing you have to pay for means failed micro inverters are out their and the clients simply dont know. Replacing failed micro's and bolt on optimisers is a massive pain for installers and JSchnee is right, we get calls everyday from people who want us to come and service (fault find, basically replace failed micro's and optimisers) but guess what we say, sorry we cant help you we are too busy doing installs and servicing our own client base. Make sure your installers are good and have been in business for a while, beware of sales guys, they dont care if the service team will be at your house every year for the next 20 years swapping out failed units.

https://www.solarreviews.com/blog/pros-and-cons-of-string-inverter-vs-microinverter

[ccjw33]

Hi ccjw33,

One other thing to keep in mind. Historically, Enphase Micros have a nasty habit of failing and needing to be replaced. While the newer models (post m215/m250) seem to be better, over the last 4 years or so Enphase has been coming out with a new model almost every year. This has made it difficult to keep track of which model revisions are working well and which ones aren't. And there hasn't been a lot of info / comments one way or the other on the newer models (S-series, IQ6-series, IQ-series).

So what I'm getting it is which every installer you choose, be sure their warranty includes the labor coverage to remove the effected panel and replace the Micro when/if it fails. Regardless of the warranty duration (10 or 25) or price, I would try (I know this is difficult) to choose the installer which is more likely to still be in business in 5 or 10yrs when components may begin to fail. Sometimes it can be difficult to find another installer who will service an existing system which they did not install themselves. Of course install quality matters, too.

All the best,
Jonathan

Thanks Jonathan. It came down to 3 installers I am negotiating right now and they all have more than 10 years experiences in the solar installation and great yelp reviews. Sunwork is actually non-profit organization which is also 16% cheaper than the quote I have received for LG 340w panels with IQ7+. They also offer LG 335w but total cost only 12% lower than the other 2 installers. Sunwork only provides 10 years warranty for workmanship and other 2 offers 25 years. Do you think I will have to spend more than $2000 between year 10-25? If that will likely happen then I think going with 25 years will be safer but if not I think going with non-profit might make more sense. There is another concern I have with the non-profit is that they recommend REC REC-315-TP2M or REC-320-NP and I did some study and found that they are also good panels but curious what you think? Thank you.

[J.P.M.]

Do you think I will have to spend more than $2000 between year 10-25? If that will likely happen then I think going with 25 years will be safer but if not I think going with non-profit might make more sense.

Besides the larger than zero probability that any installer will not be around in 10+ years, there are the considerations that a few spares bought now may be less $$ than product insurance. Or, maybe a more practical consideration: How long do you really expect to stay in your current home ? Ave. stay in the U.S. is probably somewhere between 6 -10 years. Also, I'd be safe and not plan on any added value to your property because it's got a PV system, or that product insurance will add any additional residual value to a PV system.

[Ampster]

....... Also, I'd be safe and not plan on any added value to your property because it's got a PV system, or that product insurance will add any additional residual value to a PV system.

That is probably a safe assumption, but anecdotally I did get a bump up on a recent appraisal on a house with solar. I have also own an investment property which has solar and it is my opinion that the tenants paid more for that one than similar units without solar.