Powerwall 2 Installs in Hawaii

[gmtom1]

I'm in the process of finalizing my order with Tesla to expand my current 21-panel, 5 year old system with an additional 12 panels + 2 powerwalls. The estimate materials indicate they are using 315W Hanhwa panels and solaredge string inverters. They were initially planning it as an NEM+ install, but I asked if they can check on adding it to my existing NEM, since that was approved for 10kW and I'm only at 5.25kW now with my current system.

Has anyone else been able to do this? Reading the NEM agreement, I don't see anything that would prohibit me from expanding provided I don't go over the max 10kW generation limit?

 

[rickhuizinga]

I placed a deposit for a 3.8kW system a few weeks back for installation on the Big Island. They're not yet doing installations here, and it will be interesting to see how long, if ever, they get around to it.

 

[Papafox]

Did you follow up with this and purchase? Or at least talk to a local rep?

I'm currently working with a Tesla rep in Las Vegas. Since I've run out of roof space that is level or facing the southeast, I will be placing on a roof section that is 10 degrees facing the NW. It's not optimal because I lose about 15% of power in December compared to flat roof, but it's still worthwhile. The problem is that I then have a doubling of electrical output from December to July, and I need flexibility in choosing which circuits are run from the new system, since my old system is NEM (HECO buys power back at retail and I'm credited for up to 12 months) vs NEM+ (HECO won't pay me for any excess electricity delivered to grid on the NEM+ array). I'll likely work with my electrician to set up something that will work and then will place the order with Tesla. Tesla likes to do simple installs at 4 (3.8)KW, 8KW, or 12KW. They're not really big on customization. The good news is that they would finance the solar panels plus powerwall project. Will post when I have a final solution.

 

[Papafox]

Did you follow up with this and purchase? Or at least talk to a local rep?

Tesla is offering me the Q.Antum Q Peak DUO BLK-G5/SC 310-320 panels, which are rated at 19.3% efficiency.Each panel is 66.3 inches x 29.4 inches in size.

I'd be happy to send you a PM next time I plan to swap out a micro-inverter. The Tesla system uses a traditional inverter, so the micro-inverter swapping would not be an issue with that install.

 

[gmtom1]

Tesla is offering me the Q.Antum Q Peak DUO BLK-G5/SC 310-320 panels, which are rated at 19.3% efficiency.Each panel is 66.3 inches x 29.4 inches in size.

I'd be happy to send you a PM next time I plan to swap out a micro-inverter. The Tesla system uses a traditional inverter, so the micro-inverter swapping would not be an issue with that install.

I have the same panels in my install proposal. I think mine are 315W, since they are listing it at 12 panels and 3.78kW total install. The Tesla rep said the Solar Edge string inverter is what they use standard and programmed for the Tesla app & powerwall. I've seen differences in opinion on string inverters vs. microinverters but I didn't realize you could swap them out after the fact. What are your reasons for swapping after the install? Efficiency?

 

[Papafox]

I have the same panels in my install proposal. I think mine are 315W, since they are listing it at 12 panels and 3.78kW total install. The Tesla rep said the Solar Edge string inverter is what they use standard and programmed for the Tesla app & powerwall. I've seen differences in opinion on string inverters vs. microinverters but I didn't realize you could swap them out after the fact. What are your reasons for swapping after the install? Efficiency?

The early Enphase microinverters had quality issues, and over the past five years or so more than 30% of mine have failed. The good news is that the replacement micro-inverters are somewhat more reliable. Enphase has a new line of microinverters that are both more efficient and more relaible, but they cannot be simply swapped out. If a person wants state of the art microinverters on an old system that previously used first-generation Enphase micro-inverters, a contractor needs to be hired to do the swapping and modifications, and the cost goes way up. I find that because of state and federal tax credits, the most attractive option for me (with lots of roof space) is to keep all my panels working on the old system while I add another system with a PowerWall to supplement it.

 

[Akikiki]

Agree. I HAD Enphase microinverters too. Too many failed. They gave me another just like it, but had to pay my contractor to swap it because Enphase simply stopped paying the labor. If you move to their new tech, I think its called IQ, you pay for it out of pocket and it does not qualify for tax credits. But if you add more solar, its considered a new installation and qualifies for tax credits. So, I opted to not just add (no more room on the roof) but remove 3/4th and replace with 50%+ higher performing and removed all the microinverters and went with Solaredge inverter. Very pleased with the outcome.

 

[fseir]

Did you follow up with this and purchase? Or at least talk to a local rep?

I ended up going with a local installer. I was scared away by the negative yelp reviews for Tesla, and the experience of a neighbor who had his system installed by solar city. The cost savings with Tesla would have been nice, though.

In the end, I got a 9 kW system with 2 powerwalls. Although it gets me to 99% self powered on sunny days, on cloudy days, I wish I had a larger system and a 3rd battery.

I think the panels that Tesla quoted me for were 325 or 330 watt. Ended up going with 360 watt panels due to limited roof space.

 

[Casper702]

I ordered a solar system on the Tesla website last week and they are coming by on the 23rd for a house visit. Hopefully they can get the system up and running by the end of the year.

 

[HAWX 12]

I ordered a solar system on the Tesla website last week and they are coming by on the 23rd for a house visit. Hopefully they can get the system up and running by the end of the year.

What was the local company? My first email reply is from an island Pacific solar employee.

 

[Casper702]

Not sure who the local company is yet. Tesla called me to schedule the appointment and said someone will call me the day before to confirm the appointment.

 

[Casper702]

What was the local company? My first email reply is from an island Pacific solar employee.

A Tesla employee driving a Solar City van is doing the site survey.

 

[Casper702]

Tesla is here for the home inspection

 

[gmtom1]

I signed my purchase documents with Tesla yesterday to add onto my existing system (from another installer) with 12 panels & 2 powerwalls (one of which is a founders referral). The rep said I'm looking at early to mid-December installation, which is fine with me. This 2nd system will be NEM+. I inquired about just adding onto my existing NEM agreement, since the total generation capacity of both systems is still < what HECO approved for me in my original NEM, but no-go. My read of the NEM agreement is that I can expand it up to the limit, but Tesla has a different opinion, or is unwilling to put forth the effort to push the paperwork with HECO. They also made me submit a withdrawal form too, which seemed a little weird.

Overall, from what the rep said, I'll still keep my existing system NEM and that system will export credits if my house demand is fully met and the batteries are full from my new system. I can expand the 2nd system as much as I want, so if I can't get HECO to agree to max out the original system up to the approved 10kW (perhaps via a different installer or on my own), then I'll just add more panels in the future and have the entire 5.25kW old system go straight to the grid. Another option I thought of would be to replace my old system's "defective" 250W panels with newer 360 (or greater?) panels in the future, which would effectively increase my original system output.

 

[HAWX 12]

I signed my purchase documents with Tesla yesterday to add onto my existing system (from another installer) with 12 panels & 2 powerwalls (one of which is a founders referral). The rep said I'm looking at early to mid-December installation, which is fine with me. This 2nd system will be NEM+. I inquired about just adding onto my existing NEM agreement, since the total generation capacity of both systems is still < what HECO approved for me in my original NEM, but no-go. My read of the NEM agreement is that I can expand it up to the limit, but Tesla has a different opinion, or is unwilling to put forth the effort to push the paperwork with HECO. They also made me submit a withdrawal form too, which seemed a little weird.

Overall, from what the rep said, I'll still keep my existing system NEM and that system will export credits if my house demand is fully met and the batteries are full from my new system. I can expand the 2nd system as much as I want, so if I can't get HECO to agree to max out the original system up to the approved 10kW (perhaps via a different installer or on my own), then I'll just add more panels in the future and have the entire 5.25kW old system go straight to the grid. Another option I thought of would be to replace my old system's "defective" 250W panels with newer 360 (or greater?) panels in the future, which would effectively increase my original system output.

I'm looking at almost exactly the same setup as you.
I think I might cancel however. Adding the small system from Tesla with 1 powerwall will only give me a MAX of 10kwh/day benefit. I don't think I'll even get that with my Maunawili cloud cover. $9k invest to save less than $100/month???

 

[Akikiki]

Its not just about saving money. I envy you guys doing these energy storage/Powerwalls now. I'd like to have them. But the main reason that I want them is assurance that I can still have power when the "big one" comes through here. I want more than 10 kwh/day but that's even better than 0 kwh/day. For me having the ability to use power when grid is down is more important than shaving some of my daily or monthly costs.

 

[gmtom1]

I'm looking at almost exactly the same setup as you.
I think I might cancel however. Adding the small system from Tesla with 1 powerwall will only give me a MAX of 10kwh/day benefit. I don't think I'll even get that with my Maunawili cloud cover. $9k invest to save less than $100/month???

I'm hoping to get between 13-15 additional kWh per day based on my current system's production, but as @Akikiki said, it's about backup and getting in now while the tax credits still exist and HECO still has (some form) of net metering. As much as HECO says they're planning and upgrading the grid, I suspect we'll all see more grid instability as they make mistakes trying to integrate more renewable/unstable energy into a grid that has been historically powered by stable, oil and coal fired power.

I've noticed my stove and microwave clocks blinking more frequently when I come home....

 

[Akikiki]

Your stove and microwave just missed you when you were away. They are simply showing you their love with the blinking. Smarter (and more affectionate) appliances. Your appliances are warmer than mine.

When I ask my Google Home Mini to perform something, she does and replies "Okay, turning off the whatever it is. So, I follow up with "Thank you sweetie, or honey or sugar-pea." She anti-affectionate and clearly says, "You can call me Google Assistant". Pretty cold for that female Australian voice.

 

[G'sinHawaii]

Hopefully IF/WHEN the big one comes the panels are still up there, intact and functioning....



But, I am with you and agree

Its not just about saving money. I envy you guys doing these energy storage/Powerwalls now. I'd like to have them. But the main reason that I want them is assurance that I can still have power when the "big one" comes through here. I want more than 10 kwh/day but that's even better than 0 kwh/day. For me having the ability to use power when grid is down is more important than shaving some of my daily or monthly costs.

 

[Copterguy]

Just got 15 more panels and one powerwall in today. Very happy. Keep staring at the power flow meter. Lol.
It's added to an 8 panel NEM 1 system.