roostertech
Guest
I've been on the "waitlist" since day one. Still no word.
As for power outage, my area is still one giant construction zone, so I still get short outage (10mins-an hour, often pre-notified) every month or so.
PG&E really doesn't want anyone to keep reef tanks.
- Thread starter sfsuphysics
- Start date
I've been on the "waitlist" since day one. Still no word.
As for power outage, my area is still one giant construction zone, so I still get short outage (10mins-an hour, often pre-notified) every month or so.
Flagg37
Guest
The longest outage I can recall was for the Loma Prieta earthquake. That was a little over 20 years ago though. After that it's usually no more than 2 hours. It's a local outage from a car hitting a pole or something.
sfsuphysics
Supporting Member
Exactly, getting something like the powerwall as a back up due to outage might be a bit pricey considering the alternatives for most people. That said if you want to stick it to PG&E and completely clip the wire from the grid that's perfectly fine too, just make sure you're not a huge energy hog (i.e. reef keeper 
)
A quick look shows the 14kWh Powerwall is $5500. Which for San Francisco that would be perfect for a daily usage if I were to stay under baseline... however you also need to make that much power too, and during winter months I doubt I would come close. Now if I were in a rural area, then absolutely would be worth considering, however having a generator would also be something that you would call essential equipment, plus rural = more land = more solar panels, here in SF I'm really limited to how many I can have based on geometry of my roof & local codes.
) A quick look shows the 14kWh Powerwall is $5500. Which for San Francisco that would be perfect for a daily usage if I were to stay under baseline... however you also need to make that much power too, and during winter months I doubt I would come close. Now if I were in a rural area, then absolutely would be worth considering, however having a generator would also be something that you would call essential equipment, plus rural = more land = more solar panels, here in SF I'm really limited to how many I can have based on geometry of my roof & local codes.
Flagg37
Guest
I probably don't recal any of the ones over a year ago since I didn't have a reef tank that relied on power to sustain life.
sfsuphysics
Supporting Member
yes the houses across the street from me are on a separate grid than I am. And in those instances where I've lost power it sucked seeing bright lights next door
Julius Chen
Guest
This is what I heard back from Ra Solar regarding Tesla Wall. I just installed a 9.4KW system but has not gone live yet. Questions I asked were appropriate size, whether I'd lost excess energy produced in summer.
_____________
Regarding the Tesla battery pack, their website is helpful in initially sizing the system.
https://www.tesla.com/powerwall
The representative I spoke with over the phone said that most people in the Bay Area will continue to be connected to the grid and use the batteries as emergency backup. If you do this you can utilize "load shifting" which helps you store energy during Off Peak hours and send it back to the grid during Peak hours for higher credits.
In order to have backup for your entire home, 3-4 Powerwalls are recommended. The price of each is $7,000 + tax + permit + fees (estimated to be roughly $8,000 apiece after these costs). They store 14 kWh each, so the representative said that at 40 kWh/day usage, 3 units would be conservative at 42 kWh/day and 4 units would give you more leeway at 56 kWh/day.
Concerning your winter question:
1) The solar more than likely doesn't need to be resized. Since you're still going to be connected to the grid, you can utilize the grid in the same way you are going to now in the winter months. In case of emergency with your power being out for more than 1 day in the winter months (which is unlikely) you can always allocate your Powerwalls to your most important electrical loads, thus sparing extra kWh for subsequent days.
2) The energy will not go wasted since you'll still be connected to the grid and getting credits from PG&E. In fact, your credit value will increase by sending more kWh back to the grid during peak hours. However, at a cost of ~ $30,000, it's going to take a lot of kWh credits to help you recoup your investment if you're not frequently using the emergency backup benefit. A smaller system (2 Powerwalls) could make sense to more economically back up your most important electrical loads.
_____________
Regarding the Tesla battery pack, their website is helpful in initially sizing the system.
https://www.tesla.com/powerwall
The representative I spoke with over the phone said that most people in the Bay Area will continue to be connected to the grid and use the batteries as emergency backup. If you do this you can utilize "load shifting" which helps you store energy during Off Peak hours and send it back to the grid during Peak hours for higher credits.
In order to have backup for your entire home, 3-4 Powerwalls are recommended. The price of each is $7,000 + tax + permit + fees (estimated to be roughly $8,000 apiece after these costs). They store 14 kWh each, so the representative said that at 40 kWh/day usage, 3 units would be conservative at 42 kWh/day and 4 units would give you more leeway at 56 kWh/day.
Concerning your winter question:
1) The solar more than likely doesn't need to be resized. Since you're still going to be connected to the grid, you can utilize the grid in the same way you are going to now in the winter months. In case of emergency with your power being out for more than 1 day in the winter months (which is unlikely) you can always allocate your Powerwalls to your most important electrical loads, thus sparing extra kWh for subsequent days.
2) The energy will not go wasted since you'll still be connected to the grid and getting credits from PG&E. In fact, your credit value will increase by sending more kWh back to the grid during peak hours. However, at a cost of ~ $30,000, it's going to take a lot of kWh credits to help you recoup your investment if you're not frequently using the emergency backup benefit. A smaller system (2 Powerwalls) could make sense to more economically back up your most important electrical loads.
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