You said "most". It's true that most municipalities require an electric utility connection but they don't actually state it has to be the electric utility of your local power company rather than your own generating facility.
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Optimizers... what are they good for?
- Thread starter nwdiver
- Start date
You said "most". It's true that most municipalities require an electric utility connection but they don't actually state it has to be the electric utility of your local power company rather than your own generating facility.
skepticcyclist
Member
Yes. Most. This is true. Particularly since the ones that do are in the most populated areas, which are the only regions that will have an affect from mass exodus
I have a 22kw generator on a 500 gallon tank.
I have 4 heat pump compressors on 10 minisplit heads. I do not run them all, but still, they use 50 to 70kw per day just for these! And if I add the EV car in, etc. Today my 30kw solar made only 4kwh.
So folks that do not have heat pumps had NO idea how much these use in the winter, when cold!!
On a good day in winter I am making 30kwh, so you can add for most than real usage onto these numbers
The problem arises when people pursue micros based on the narrative that they're better for shading or reliability or troubleshooting which is generally not true. It get even worse because they're essentially used as a crutch so XYZ solar company can hire solar installers that don't know anything about solar. So people end up paying a premium on equipment to make up for less skilled labor.
NEM 3.0 makes an understanding of solar even more critical. It's a lot easier to add storage to a hybrid inverter than micros. The GroWatt inverters I'm using now can be oversized by 200% on the AC side and can divert 'clipped' energy into a battery. So you can cram 20kW into a 10kW inverter. With NEM 3.0 when energy is produced becomes more important than how much. Much easier to oversize a string system than a micro system.
The comparison between the customer I'm attempting to help fix his system with a 16kW array I installed last year brought this to the front of my mind. The inverter for the 16kW system was ~$1500.... and it's a hybrid. For ~$6k we can add batteries to it. Micros for a 16kW array would have run ~$7k. Another $12k for storage. That's an insane price difference. And when you have an oversized array your line losses at peak produce are free since it's energy that would have been curtailed anyway. If you use micros none of it is free.
Strange. My system is literally half the size of yours but on a good day I'm making 45ish this time of year. Yesterday was quite overcast and I still made 38kwh. Is it your placement of the panels? Mine are all due south elevated at 25 degrees.
What are you making on best days in April through June? I'm hitting 88 to 90 on the best days. Do you have tree cover in the winter?
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Aren't optimizers the worst of both worlds? You have optimizers on each panel plus a central DC to AC inverter.
I think I've point blank asked you what areas these are and you've never answered me. Can you spell out in simple terms where these houses are you know personally that are off grid?
One in San Jose, one in Morgan Hill, one in Merced, and one in the Santa Cruz mountains. I'm not giving you addresses.
I don't recall you asking me where before.
It's almost not worth a response since stating that optimizers are the worst of both worlds just plain doesn't make any sense. If you knew what optimizers did, you wouldn't have made the statement.
At any rate, I'm not going to rely on IR guns to possibly diagnose a bad panel as a single panel going bad is unlikely to be very obvious causing me to run out and try and diagnose it with my ST-80 or FLIR imager.
If a panel goes bad, I'll get a notification as soon as it goes bad because I have optimizers and as soon as a panel goes too low or stops producing power, I'll get notified. Also useful for shading that increased due to tree growth. Without the optimizers, I can't tell if there is a partial reduction or shading of a panel unless I'm out there looking all the time for shade and if there's a weak panel, I'll probably never notice without panel level production numbers.
I'd still prefer micro inverters over optimizers as they can provide all the benefits of optimizers without the all your eggs in one basket downsides of having a single inverter.
Yep, a lot of my 90 panels are not at a great angle!! Many are north.
The best I get is 185kwh in a day, so I can produce lots.
I don't think this is really done anymore even though pro-strings people keep bringing it up. I rarely see this much on solar reddit and as I keep saying, the cost in an overall project is pretty insignificant. I think for me, it was like $1k-$2k for $45k job not even including the tax credit. I still don't see from your example how troubleshooting a string was easier than a micro to find that dead panel.
Even though $1 or 2k is $1 or 2k, for residential where folks have limited space on a roof, it's still a no brainer of course, all IMO when you can only have so many panels up there, especially for homes in CA. You sound like a fairly technical owner yourself, but I think for the masses of clueless solar home owners, I'm still not a fan of strings and wouldn't suggest them.
In the example you bring up with the financial $ numbers, do you do this as a full time job now or you are doing this as a favor for a friend at reduced cost or just as a favor for a beer? I'm not familiar with hybrid inverters, but have seen micros now which do support multiple panels for lower cost. It's not a fair comparison I feel from what I've seen since you aren't getting the same redundancy.
I'm sure for folks who complain about having a basic string inverter off-line for 3 months or longer (those posts are all over TMC regularly), the solar production lost FAR outweighs the cost savings from the string vs. micro debate. There are very few micro complaints which pop up here from what I've noticed.
I'd be curious on the San Jose one for sure and understand not sharing addresses and don't expect you to, but understanding more on how/why/any utility issues before they went off grid would help the discussions for sure.
Like that Palo Alto owner I think it was who was asked for hundreds of thousands of utility upgrades to be connected to the grid, those edge cases don't apply to the 85% of most owners out there and my belief (maybe wrongly) is that it's not as simple as you claim.
I guess the good thing is as the IOUs ramp up cost, perhaps more and more people will consider this route and post/share/youtube all of it for the rest of us, especially more well to do folks.
How many micros was $4k? I see end user prices for iq7+ for $147 and iq8 of $200, but this is from an installer with marked up prices and not direct during an install. Maybe some of the installers here can chime in what they charge end users.
You also need an an enphase combiner which adds ~$500. The cables to interconnect micros are ~$20 each. If you want to have backup you need a smart controller which adds ~$2k. Then the batteries are ~2x the price since every battery is AC coupled so it includes it's own inverter(s).
Solar Edge has been having severe quality issues. It would be interesting to know how much of the 'stink' on string inverters is due to the high failure rate of Solar Edge. We've replaced 4 Solar Edge inverters in ~2 years. One was replaced twice. I've had 2 SMA failures with ~10 y/o inverters but none with the 'new' ~5 y/o models.
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No need for insults. We are a better forum than that.
Fair enough. My comment was in relation to reliability/redundancy. I didn't appreciate panel level monitoring was your number one priority.
skepticcyclist
Member
That is just a one item and much less expensive than an inverter and gateway
Don't they already have interconnection cables?
Aren't Tesla batteries are also AC coupled?
My SE is just a time bomb waiting to happen. When it was first installed, I was shocked how hot it ran during the summer without active cooling relying on just the heat sink on the back as a passive radiator. I 3d printed cowls that sit on top with 2 large PC fans that pull air that I use in the summer which keeps the heat sink more than 100F cooler.
