jhm
Well-Known Member
What if the battery was also the inverter for the solar system? Even if this could not fully qualify for ITC, I think it could be cost effective to design a stationary unit that would also double as a solar inverter.
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What if the battery was also the inverter for the solar system? Even if this could not fully qualify for ITC, I think it could be cost effective to design a stationary unit that would also double as a solar inverter.
InTheShadows
Active Member
It all depends on how it is used. If you are peak shaving and you have a system that is sized correctly it will be hard to say it's not charged from solar (at least with the outback radian system) even if it is AC coupled.
I agree that putting one solar panel on a roof and hooking a 10kwh battery bank to it isn't going to fly. But a 7-8kw solar array will absolutely qualify. In the most extreme cases at least partially.
I have prospects and past customers lined up waiting for this announcement that have no intentions of using the pack for peak shaving. They want it to go off grid. Not like building a cabin in the woods, but installing the system at their home with solar and disconnecting their utility service.
You mean something like the SMA TL inverter model? Or the Enphase AC module inverter with onboard battery?
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You are in PA and are taking people off the grid? Why? Rates in PA are reasonable from the grid. Even PECO is under .17/kWh. For off grid, ITC is fine. But I am seriously thinking there will major tax abuse in states like CA and NY. Are they sizing batteries large enough for 3-5 days of power during multi-day cloudy events? Generator as well in case SOC drops too low? This sounds like a rare occurrence and some folks surely are willing to spend a lot to feel like they are advancing by being off the grid. A whole house off grid system can be quite a hobbyist delight. Are they prepared for the usual plans of inverter replacement after 10-15 years, battery replacement over the course of the same time (more often with lead acid) and why haven't they considered existing technologies on the market already, such as other inverters and Lithium batteries which are not Tesla? Do you have a price list for Tesla packs yet in areas which have no heavy incentives? I am familiar with PA hving a small battery program in their sunshine program.
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InTheShadows
Active Member
No, full blown battery backup systems. Someone that wants a battery based solar system to use for backup if the power goes out completely qualifies for the full tax credit, no questions asked as long as they are not peak shaving. The solar panels are the primary charge source for the batteries. They are only charged from the grid when they get dangerously low. You can even turn the grid charger portion off then there are no questions at all where the charge is coming from.
InTheShadows
Active Member
Short-Term TSLA Price Movements - 2015
People buy Tesla's when it's not necessary either.
2-3 days autonomy and they have to use backup generators. It won't pass code with out an auto standby generator. However we have had two customers turn the auto standby off. They want to consciously pull the cord to use the generator. They have a light that goes off when the power drops too low then they enter super conserve mode. No tv's, no computers, on fans, etc until the light comes back on.
Most of our customers now are not going solar for the financial payback. Most of our trade area has rates of .08-.13, favoring the low side of that. They are doing it because they care about the environment.
They also no longer qualify for Srecs after they unplug.
This is OT and should be moved somewhere better fitting. Sorry.
People buy Tesla's when it's not necessary either.
2-3 days autonomy and they have to use backup generators. It won't pass code with out an auto standby generator. However we have had two customers turn the auto standby off. They want to consciously pull the cord to use the generator. They have a light that goes off when the power drops too low then they enter super conserve mode. No tv's, no computers, on fans, etc until the light comes back on.
Most of our customers now are not going solar for the financial payback. Most of our trade area has rates of .08-.13, favoring the low side of that. They are doing it because they care about the environment.
They also no longer qualify for Srecs after they unplug.
This is OT and should be moved somewhere better fitting. Sorry.
Agreed. The incremental cost of going from 7 kWh to 10 kWh is $500, or $167/kWh. That's any amazing price for batteries. I'm going to need to make some inquiries about grid-scale batteries.
dhanson865
Well-Known Member
It's not a capacity change, its an overprovisioning change. I believe both products have the same amount of cells but one is optimized for weekly cycling and one is optimized for daily.
If you are going off grid you want the 7 kWh because it is setup to survive the power draw every night and charge every day.
If you are staying on grid you want the 10 kWh because you don't have to stress it as much and you get a larger reserve for outages.
Similar to how SSDs are over provisioned. Spare capacity reserved for wear leveling/reliability.
The other possibility is one has less cells but more heatsink/cooling capacity.
Since they are stackable you get overlapping capacities
Weekly
10, 20, 30, 40, 50, 60, 70, 80, 90
Daily
7, 14, 21, 28, 35, 42, 49, 56, 63
assuming I'm not too tired to type the powers of 7.
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Solar+SuperCapacitorBattery = (Near)Free in 20 years;
No grid, No distribution, No losses; (Near)No Cost
CapCost in today's $s:
~ $3000 total amort over 20 years (Near-Free)
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I do not think this is correct. Did you see that somewhere or hear Elon say it or your own reasoning? If that was the case I dont think their would be a price difference. If they had the same number of cells they would not charge you 500 bucks less for the 7KWh PowerWall
I dont think so Ocelot Did you see this linked upthread Press Kit | Tesla Motors Info in video left out of there was.... the home battery is available in different colors, The whole event was powered off of the batteries which had been charged by the solar panels on the roof. I dont remember if they repost the live events but someone there normally gets a pretty decent video
The $3.5k is for the battery only. That's the price to installers, not retail to home owners. After the installer (like Solarcity), retail price offered to home owner. Once installed, installers like Solarcity get the SGIP incentives in CA if available... Presumably this SGIP incentive is rolled into the lease cost so they can do their $0 down lease package deal. ITC for solar install, SGIP incentive for the battery(in CA).
CapitalistOppressor
Active Member
I don't think it's a cell count issue. Probably just more cooling and more durable power electronics.
Also, aside from cell count the other possibility is a different chemistry. But I'm even more skeptical of that option because the economics kinda suck. Functionally though it might fit the pricing and stated performance differences better than the alternatives. If I was going try to develop an argument one way or another, cell chemistry is where I would start spending mental energy first.
Honestly though I don't care. As an investor I think that the light duty backup battery is probably an edge case for the near term. The initial opportunity is much more in the commercial market, and the deep cycling battery is much closer to what will be used in that market.
And if they can build big boxes for ~$500/kWh they blow else out of the water.
The Powerwall is available in 10kWh (kilowatt hours) optimized for backup applications or 7kWh optimized for daily use applications. Both can be connected with solar or grid and both can provide backup power. The 10kWh Powerwall is optimized to provide backup when the grid goes down, providing power for your home when you need it most. When paired with solar power, the 7kWh Powerwall can be used in daily cycling to extend the environmental and cost benefits of solar into the night when sunlight is unavailable.
Directly from Tesla is where you got it. My apologies there.
larmor
Active Member
Will the powerwall product be available overseas? I ask, since, from my experience with Pakistan, there is a huge problem with energy distribution and supply, and the supply is not keeping pace with demand. The infrastructure is lagging behind. And there are huge homes there as well as numerous mills and factories, and software development houses.
I think the more compelling argument for a powerwall product is for emerging markets... Thoughts?
I think the more compelling argument for a powerwall product is for emerging markets... Thoughts?
InTheShadows
Active Member
Probably not yet.
This is one of the great things about this product that not many people know about.
We want it in the USA so we can make our lattes at noon cheaper and so we can watch tv (no kidding, that is second on the list when I ask customers what loads they want backed up, first is the fridge.) and use our play stations when the power goes out.
Other countries want it so they can have running water and lights to read. And there are so many countries that want it for those reasons.
The demand for this product is so massive.
I want to see the installation manual so I can create the materials take-off for it so I can start offering it to our customers. I hope I can get through to my Tesla contact tomorrow.
The thing is when you do get access to it your country will see a massive shift. Just like the countries that had their lives changed overnight when cell phones became affordable and they instantly had communication with the world. Other countries will be impacted to this extent too.
InTheShadows
Active Member
You know which other company this is going to hurt? GNRC.
And it looks like they just had ER and had a miss.
And it looks like they just had ER and had a miss.
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