Well, for my situation the primary usage of the battery is not as a backup system, but as a primary supplement to the solar panels. It’s not really practical to use a generator for this purpose. The battery on the other hand is quite convenient. I was reluctant to pull the trigger on panels alone, but now that the battery is available it really wasn’t a hard decision any more.
How did the Tesla battery compare with traditional batteries in your research?
There’s not that many on the market right now, but most were either more expensive, or lower capacity. The price point of the Powerwall 2.0 is about $5,500 gross. There is a federal tax credit of 30% so that drops the price a bit too. The Tesla one also has the inverter included within the unit itself - many others had separate inverters or had to be separately purchased. As far as home batteries go, it’s a pretty competitive price.
I like the integration of the battery with the solar purchase and not many others did that. I think SunRun does it, but their’s is more expensive for less output. I also think there will be consolidation in the solar market and if I had to bet I’d say Solar City (Tesla) will outlast many of the others. It’s definitely not for everyone - a high up front cost is enough to ward many away. But the ability to use near zero from the grid and have that redundancy is valuable to me.
In between posts I executed the contract to purchase the panels, and two of the battery units. Now I wait for site review and installation.
Can you explain what you mean by this? Not allowed by what?
Not allowed by the Public Utilities Commission IIRC. The limit is imposed so people don’t become net providers of power back to the grid.
Ah, I see, thanks. Can’t you physically disconnect from the grid and generate whatever you want?
where would his >105% generation go, if not back into the grid?
My son has an emergency gas generator and it is extremely noisy. And he has to run it every month or so. So I would be reluctant to make it my only energy source. His neighbors don’t like it, but like it better when he invites them in during a power failure.
Don’t know, I’m not familiar with how that works. If that is it, then okay.
Bone, the battery might circumvent the problem with excess generation. As I understand it, the restrictions on how much power you can put back into the grid are pertinent for situations where there isn’t onsite storage. In that situation, you generate excess power during the day, which is fed into the grid. You then draw power from the grid at night.
With battery storage, you are storing the power you generate during the day for use at night. Depending on your generation and usage, you might still need to draw from the grid on some nights, or you might have excess some days if the batteries are full. But this isn’t the typical net-metering situation, and it is probably regulated differently.
True - I’m using SolarCity as the installer since they are the ones selling the Powerwall battery. They handle the permitting and limits so I’m relying on their expertise. And while not typical, with the more wide scale deployment of this battery I think adoption will grow.
I’m sure there will be some days where I use more than I generate so will need to draw from the grid. Over the year the hope is that this is net zero. I am buying two batteries for redundancy and to smooth out those fluctuations even further.
Tesla -Solar Shingles, Powerwall home battery, SolarCity for panels . You can see where this is going. Oh yeah, and they do that thing with cars.
I would be concerned about having large Lithium batteries inside a house. What if they decide to “vent with flame” while the family is sleeping? There’s the hydrogen issue with lead batteries. It seems like it would be good to have either kind stored in some sort of shed separated from the house. But that would add to the cost.