Who's gone Solar

[mrzuzzo]

Can you summarize your various quotes and give pricing on a per kW basis?

My brother is adding a second system to his house with intent to get under NEM2. He has quoted Tesla installation with significant savings over others…a big reason is the use of string inverters versus micro inverters. He is taking the gamble with the string inverters since he has no shading concerns, coupled with Tesla’s minimum production guarantee (meaning any potential system outage may still be paid as if somewhat functional).

Modern string inverters like SolarEdge come with power optimizers so panel shading is not a concern.

 

[250mL]

Modern string inverters like SolarEdge come with power optimizers so panel shading is not a concern.

Thanks for that. My brother said his quote was minus the power optimisers because he has zero shade concerns, but the power optimisers are certainly something Tesla can install if the situation warrants it.

Having said that, the Tesla quote still seemed waaaay less expensive, despite not having the optimisers. Let me see if I can get his pricing breakdown…but prices ranged all over the place:

$2,690/kW - string inverter, no power optimisers
$3,555/kW - IQ8 micro inverters
$4,190/kW - IQ8 micro inverters
$4,200/kW - IQ8 micro inverters

 

[HappyHighwayman]

Those numbers don't show what you get at each higher price level.

 

[250mL]

All using recognised name brand panels, with comparable rated overall power output.

Also takes into account any subcontractors needed for additional sub panel.

 

[HappyHighwayman]

Ah I see

 

[byke]

That was the plan, in the back of my head all along, and I probably failed to articulate that to the companies bidding for the project.

I'm hoping this works out. Please post up the details on how that conversation goes.

that's my plan. I have hybrid service and no battery. the battery would have been for emergency backup, in which I have never lost power to my house in over 20 years. Not a big need for me, but I do want the ability to have a battery and of course this whole thing about PGE could start charging us daily for use and production (i.e. pay us pennies/kWh when we make it, while charging us full cost to get it back from them).

So you have this setup right now, a "battery ready" solar system with hybrid inverter? Was that a pain to get them to agree to?

Also, I have an older Nissan Leaf in which when I would upgrade the battery, I'd like to re-use the old battery cells as the backup battery system for the house. It's doable but kind of fringe right now. Hopefully in a few years there will be more technicians out there who can do this service more easily.

I really want a new leaf, but it seems like the batteries weren't so awesome on the older ones? But, even if an old 40kwh Leaf battery were running at half capacity, that would still totally be worth it. Put 6-7 of them in series and build 48v packs, easy to get bms' for and wire as many as you're able to in parallel. Could be bitchin'.

 

[Bubba_s]

I love the idea of cheap batteries that you can drive around if you really need to. What a world.

 

[scratchpad]

Average your usage over multiple years. Gives you a better average usage to work with to estimate size for your solar system.
Electricity is billed for the year through net energy metering(NEM). If you elect to goes balls deep on A/C in the summer, it could balance out that monthly average during the winter. Better for your wallet to NOT go crazy on A/C either way.
I'm going the opposite way. Making anything that produces heat to be gas-based.
Electricity is a high quality, low entropy form of energy. As such it is very versatile. Save electricity for tasks other lower quality forms of energy like fossil fuels cannot do - like powering the screen your reading this from.

Heating with electrical resistance is like cutting butter with a chain saw. Besides, as a heating source, nat. gas is usually cheaper than electric resistance heating.
It's important to understand your energy usage and properly size your system. The general consensus here is correct, you're going to get pennies on the dollar for "overage" you get on your NEM/true-up, so don't waste a bunch of money building the biggest you can. Batteries change the equation, but you must also measure the initial cost and ROI vs your usage.

The average we used for 2021 & 2022 is 14000 kwh. Not sure how thatd be converted into making sure wed get proper panel sizing when getting estimates.

What you say about making anything that produces heat to be gas-based totally makes cents. When i was writing that all i could think about was the cost $3+/gallon propane to fill up 250 gallon tank 2X year. For the most part, most of the propane is used in the winter when drying clothes and if we run the furnace. Summertime, we hang dry clothes.

 

[flips21]

So you have this setup right now, a "battery ready" solar system with hybrid inverter? Was that a pain to get them to agree to?

The Enphase IQ8 is a hybrid inverter. My installer upgraded me from the IQ7 because it became available during the permit process. Retail, they are only a few bucks more, so basically my installer just went with the most current micro inverter Enphase was putting out and ate the cost difference.

The IQ8 has the ability to provide backup power with batteries, (the conventional form of backup), or with whatever the panels are generating (Sun only backup), To take advantage of this ability, you need an additional smart panel. The smart panel is wired like a typical generator backup sub panel that includes the brains to tell the IQ8s to modulate thier output to match the backup circuit demand if there is more sun available than needed while also being able to turn on and off the various backup circuits when there isn't enough sun, Adding a battery gives it more flexibility.

My house has whole house gas generator backup, so there is no reason for me to take advantage of this feature so I didn't get the smart panel. But, I could in the future. The IQ8 costs about $20 more than the non-hybrid IQ7, which appears to be phasing out.

Flip

 

[flips21]

I love the idea of cheap batteries that you can drive around if you really need to. What a world.

Some things to consider when getting a new system if you want to explore this route;

1. The car battery backup model saves you $ in three ways
a. Car batteries can be cheaper than on the wall batteries (for example, the extended range Ford Lightning XL has the capacity of 7 Tesla Walls available for around $50K instead of the (very) rough cost of $70K for 7 Tesla Walls.
b. Many localities have house construction upgrades required before being able to install wall mounted batteries. In Santa Rosa, I would have to add fire sprinklers to my house for the garage before installing batteries in the garage.
c. You get much of the utility of an EV with the advantage of battery backup increasing the value of the $ spent.

But, as of 8 months ago, the market was still trying to figure things out. I am not aware of a standard in place that allows you to use any battery backup capable EV with any solar system controller. In the case of the Lightning, I believe that Ford is working with Sunrun and you need Sunrun's controller. So, you need to match your components; Inverters, Controller and Vehicle to get a system than would work today.

Another limitation to the EV/Backup model is that if you use an EV's battery as a house battery to time shift your power to the utility, which is one of the incentivised goals of NEM3, you are using up battery cycles for the house electrical bill and not for driving, so the EV battery will be used up in the car at a much lower mileage so you get less life than with a standard EV and, conversely, you can't charge the vehicle off solar power if you use it for commuting.

Flip

 

[byke]

Super cool that-that setup is becoming standardized. Still sounds a little weird though. Because of their configuration with each micro inverter being individually attached at the panel, there's no way to utilize the inverter functionality unless the battery is tapped into the dc/panel side of each inverter. Meaning, they're inverters that can only be used in the daytime and you'd need yet another inverter of roughly equal total power in order to have a dc-to-ac inverter that functions with your battery at night, which means you should ditch all the micro's and just go with a single? Or, maybe that's what they do, run thirty pairs of parallel leads off the battery into a solar/battery dc input on each inverter?

 

[supaflyryan]

This is a great thread, thanks for all the info.

We just bought a new house and it primarily has a flat roof (well, very slight grades for drainage). The roof itself will need to be "replaced" (not sure what that entails when there's no shingles or tiles) in the next couple years, which it sounds like we should do before considering solar.

Are there any special considerations or pros/cons to having a flat roof? I'm guessing there's more available sq. footage considering nothing is pointing "away" from the sun, but also nothing pointing directly at it.

 

[scratchpad]

Has anybody used SunRun through Costco?

 

[Bowling4Bikes]

I'm hoping this works out. Please post up the details on how that conversation goes.



So you have this setup right now, a "battery ready" solar system with hybrid inverter? Was that a pain to get them to agree to?

maybe I'm not understanding what "hybrid" is, other than the inverter can accept power from PGE or my panels, and can distribute excess power to PGE. That's what I have. If so, no it wasn't a hassle at all. we discussed getting a battery and decided against it for now.

I really want a new leaf, but it seems like the batteries weren't so awesome on the older ones? But, even if an old 40kwh Leaf battery were running at half capacity, that would still totally be worth it. Put 6-7 of them in series and build 48v packs, easy to get bms' for and wire as many as you're able to in parallel. Could be bitchin'.

yes I've seen a youtube DIY setup that looks a little junky but def. functional. The leaf batteries are in a sealed plastic "bin" for lack of a better word. Once the bin is cracked open, it's just several small battery cells. The yt DIYers make it look easy but there's a few steps where it looks like there's some electrocution concerns lol. Me, personally, would use a professional if one ever becomes available.

From what I understand the Nissan tech that keeps the Leaf battery cool and helps with longevity hasn't changed too much over the years. So even though the new Leafs have a higher range, I think they have the same problems of degrading performance over time. My 2012 gets about 25 miles range now...pretty shitty for a car, but still has a ton of juice to be a battery for a house.

 

[mercurial]

Super cool that-that setup is becoming standardized. Still sounds a little weird though. Because of their configuration with each micro inverter being individually attached at the panel, there's no way to utilize the inverter functionality unless the battery is tapped into the dc/panel side of each inverter. Meaning, they're inverters that can only be used in the daytime and you'd need yet another inverter of roughly equal total power in order to have a dc-to-ac inverter that functions with your battery at night, which means you should ditch all the micro's and just go with a single? Or, maybe that's what they do, run thirty pairs of parallel leads off the battery into a solar/battery dc input on each inverter?

Microinverters are already a bit of a nasty design, in that now you have 20+ different points of failure that require expensive roof-side labor to replace. And now even more functionality at the panel? That's a big "no thanks dog" for me, I want my panels as stupid (and reliable) as possible.

But, as of 8 months ago, the market was still trying to figure things out. I am not aware of a standard in place that allows you to use any battery backup capable EV with any solar system controller. In the case of the Lightning, I believe that Ford is working with Sunrun and you need Sunrun's controller. So, you need to match your components; Inverters, Controller and Vehicle to get a system than would work today.

Another limitation to the EV/Backup model is that if you use an EV's battery as a house battery to time shift your power to the utility, which is one of the incentivised goals of NEM3, you are using up battery cycles for the house electrical bill and not for driving, so the EV battery will be used up in the car at a much lower mileage so you get less life than with a standard EV and, conversely, you can't charge the vehicle off solar power if you use it for commuting.

Another big "no thanks" for me. Anyone in technology knows, you need to avoid vendor lock-in like the plague. It just guarantees you either get soaked due to proprietary part selection, or even worse, your entire system becomes obsolete before you've captured the depreciation.

Also using your car to power your home at night, so you wake up to a low car battery when you have to drive? How does that make sense for anyone except someone that doesn't go anywhere during the day, and keeps their car charging at their house?

 

[byke]

maybe I'm not understanding what "hybrid" is, other than the inverter can accept power from PGE or my panels, and can distribute excess power to PGE. That's what I have. If so, no it wasn't a hassle at all. we discussed getting a battery and decided against it for now.

Most systems use grid-tie inverters where they sync their ac output with the ac from the grid and that syncing is required for them to operate. If the grid goes down, they turn off completely and you get no power from solar either. This is a safety feature, because unless you had the ability to automatically isolate pge power when pge is down, you'd be putting voltage on the lines, which the old concern is that you can kill linemen. Not so much these days with isolated boom trucks and the grounding they do on both sides of whatever they're working on, but still something we all want to avoid.

Then you have off-grid inverters that will only operate in complete isolation from pge power(or any other ac source, generator, etc.). Trying to combine power from the off-grid inverter with ac power from any other source will destroy the inverter. A hybrid inverter has the ability to do both, where it can operate with or without grid power. You can put it in grid-tie mode and it will shut off when the power is out so you get that anti-islanding safety feature, then you isolate your house from the grid and flip the inverter over to off-grid mode to run on battery. I have this one for a hobby-quality outage backup setup that I'll put together in the spring/summer. This isn't commercial(residential) quality though, more like amazon quality. I'm not sure what's out there for the pro stuff.

Microinverters are already a bit of a nasty design, in that now you have 20+ different points of failure that require expensive roof-side labor to replace. And now even more functionality at the panel? That's a big "no thanks dog" for me, I want my panels as stupid (and reliable) as possible.

The downside of 20 points of failure is also the upside, because if one goes bad, you still have the others. Your $4k investment drops to $3800, as opposed to zero(depending on what you would have hypothetically had for a single inverter of course). They're fine for people that are into solar for the numbers game. For me, I'm just tired of running the generator all day long when the power is out.

 

[scratchpad]

Called Costcos SunRun program and a SunRun consultant called me back. Here's the proposal.

$51,831
11.70 kw system
16,794 kwh annual production (14,000 is my average over the last 2 years)
118% usage offset
30 panels- JA Solar JAM54S31-390/MR (12 year product warranty) - All panels facing West on roof
2 inverters- SolarEdge Technologies SE3800H-USMN (12 year product warranty)
10 Yr Workmanship Warranty
15 Yr Roof Penetration Warranty

Heres whats interesting. Costco states 10% of cost gift card on solar purchase. So on the proposal theres a $1,176 from Costco. I ask the guy about it and he states the 10% is only on equipment. Then, i ask him what the remaining $40,000 cost is for. This consultant really didnt have answers to my questions other than his response "thats a really good question".

I have 2 more companies coming out soon. Doubtful i will use SunRun.

 

[HappyHighwayman]

I paid ~50% of that for ~50% of the power. 26% back from government.

 

[Starpower]

Be sure to shop around. You should see 25-30 year warranties on the panels. I would also suggest that you go with smaller co's. When I retired 4 years ago equipment costs were about the same as now and I was charging $2.80/Wdc (nameplate) fully installed same warranties. I had a small 3 man crew and worked from my home 1200 sq.ft. shop. Never spent a nickel on ad's and had to turn away 70% of inquiries, too busy. My same county competitors were between $2.50/Wdc to $4. 10 year workmanship and power warranties are state mandatory. Specific Roof penetration warranties are optional, but fall under the 10 year workmanship, for coverage anyway. In over 30 years of installs and 1000's of roof holes I've not had one leak and the systems are even better today. Support the little guy and save big!

 

[Bubba_s]

Be sure to shop around. You should see 25-30 year warranties on the panels. I would also suggest that you go with smaller co's. When I retired 4 years ago equipment costs were about the same as now and I was charging $2.80/Wdc (nameplate) fully installed same warranties. I had a small 3 man crew and worked from my home 1200 sq.ft. shop. Never spent a nickel on ad's and had to turn away 70% of inquiries, too busy. My same county competitors were between $2.50/Wdc to $4. 10 year workmanship and power warranties are state mandatory. Specific Roof penetration warranties are optional, but fall under the 10 year workmanship, for coverage anyway. In over 30 years of installs and 1000's of roof holes I've not had one leak and the systems are even better today. Support the little guy and save big!

Can you come out of retirement for teh BARFs?