How long a period does one need to show that data? Months? Years?......Those taking the credit just need to have data stored for the charge cycles.....
You can install our site as a web app on your iOS device by utilizing the Add to Home Screen feature in Safari. Please see this thread for more details on this.
Note: This feature may not be available in some browsers.
How long a period does one need to show that data? Months? Years?......Those taking the credit just need to have data stored for the charge cycles.....
How long a period does one need to show that data? Months? Years?
I would presume that you would have to include all the data from installation until the end of the tax year that you take the credit in order to determine how much of the credit you can take. Since you take the credit entirely in the first year, I would have to wonder on what basis they could ask you for further data beyond that tax year.How long a period does one need to show that data? Months? Years?
I'm interested in getting a Powerwall2 for emergency backup purposes. Is the main purpose of the Powerball to shift TOU or as a backup in case of power outages or some combination of both ? Does it even make sense to have a Powerwall with the sole purpose of backup power ?
Thanks !
For places with high electricity costs, eg Australia, PW2 can save you a fair bit of money, pay for itself in 5-6 years, and deal with blackouts too. I've just done a detailed review of my install here:
www.mikesgear.com
Regarding the switchover time during a power failure, from what I have seen of the Energy Gateway pictures posted on another thread, it looks like it is not a typical transfer switch that would be used on something like a generator backup. It isn't a double pole double throw switch/relay that allows selecting either the Powerwall or the normal power line. It simply disconnects from the powerline when the power line is down. It can do this by simply using the power line to supply the coil current to the double pole single throw relay.
It's then up to the Powerwall and inverter to get up to speed to supply the required power. This can be very quick with proper design. You may not even notice the changeover.
You may not even notice the changeover
Anybody on this board likely has an EV, even if not a Tesla. The E-TOU and EL-TOU are terrible for EV drivers. You are much better off on the PG&E EV rate schedule. Here is my estimation of annual arbitrage savings when on the PG&E EV rate schedule. The assumption is that the battery is charged by solar during the Part-Peak hours on weekdays, Off-Peak hours on weekends and is discharged a fixed 10kWh/day during the Peak rate period, regardless of your actual power use. Accounting for weekends this way (2/7ths of the number of days in the season) gives you an extra $100/year in arbitrage. The Powerwall will have to push the energy out faster on the weekend because weekday Peak is 2-9pm (7 hours) while the weekend Peak is 3-7pm (4 hours). Anyway, this is completely dependent on the way Tesla sets up the strategy in the firmware, which it appears customers have no control over.The power differential of $.33 per KWh is only available during the summertime. Wintertime differential is only $.20 which then stretches your payback time to ~14 years.
Additionally PGE is phasing out the old time of use rates. The new rate is almost a flat schedule which negates the benefits of the powerwall altogether, and making solar more difficult to get a return for the consumer.
Pacific Gas & Electric - Tariffs
I never thought about it, but you're right, it's probably just a single throw disconnect, not double throw.Regarding the switchover time during a power failure, from what I have seen of the Energy Gateway pictures posted on another thread, it looks like it is not a typical transfer switch that would be used on something like a generator backup. It isn't a double pole double throw switch/relay that allows selecting either the Powerwall or the normal power line. It simply disconnects from the powerline when the power line is down. It can do this by simply using the power line to supply the coil current to the double pole single throw relay.
It's then up to the Powerwall and inverter to get up to speed to supply the required power. This can be very quick with proper design. You may not even notice the changeover.
Anybody on this board likely has an EV, even if not a Tesla. The E-TOU and EL-TOU are terrible for EV drivers. You are much better off on the PG&E EV rate schedule. Here is my estimation of annual arbitrage savings when on the PG&E EV rate schedule. The assumption is that the battery is charged by solar during the Part-Peak hours on weekdays, Off-Peak hours on weekends and is discharged a fixed 10kWh/day during the Peak rate period, regardless of your actual power use. Accounting for weekends this way (2/7ths of the number of days in the season) gives you an extra $100/year in arbitrage. The Powerwall will have to push the energy out faster on the weekend because weekday Peak is 2-9pm (7 hours) while the weekend Peak is 3-7pm (4 hours). Anyway, this is completely dependent on the way Tesla sets up the strategy in the firmware, which it appears customers have no control over.
Long story short, you could arbitrage $700/year purely charging on solar and discharging 10 of 13 kWh per PowerWall per day.
View attachment 231037
...do you get any fed tax credit for PW2 like with solar?..
There is a thread just talking about the tax credit.I don't think so but there might be a proposal for it:
A new bipartisan effort to introduce a 30% Tax Credit (just like Solar Power) for energy storage
TOU schedules comparisons really depends on how much PV generation matches/overproduces and overall usage. We moved over to EV schedule in SDGE since our PV system is undersized at 3.8kw only with 2 EVs.
That said, forget PW2. I want V2H. Why invest in another battery when we have 50+KwH sitting idle in the driveway at the shoulder time when the PV dies out and out utilization spikes.
All our OHM alerts these days are the shoulder periods since we have so much solar production now with the duckbill phenomena.
V2H solution for those with PV/Central Inverter already is easy gain. Of course Tesla PW2 would die because of that (hence no push from Tesla to support V2H).