Pretty sure OCtoSV is up north and they may have blackouts/brownouts so a powerwall makes sense. Down here we don't get hit with that much and between me and Cares, the #'s don't make sense to get a powerwall unless you have OCtoSV's use case or something else you need to store power for, growing weed, mining etherium/bitcoin, whatever it might be.
Tesla Solar Panels Price Cut
- Thread starter woodburyowner
- Start date
NEW -> Contingent Buyer Assistance Program
So can you set the PW to store electricity only during off peak time and then during peak time, sell the energy to the grid at the higher rate?
there are two ways to "sell" energy back to the grid in CA. one way is you get storage credits with your provider that are used to deduct against your metered usage. so if you "sell" energy during peak times, and use grid supply during non peak times, you come out ahead.
at end of year, any excess credits are liquidated at wholesale prices. so if you rely entirely on solar and PW and never use your banked credits you are getting a lower rate for your excess production. but you may value the energy independence more highly.
Also to fix energy costs. Avg PGE bill is almost $200 and rising rapidly. Couple that with stressed generation and transmission capability and fire related blackouts (even though my neighborhood has buried utilities) and the 26% federal subsidy and it just made too much sense.
No storage because I'll produce more power than I use, I'll generate about 15-16 kw per year depending upon the weather. I'll probably use 6 kw for the home + 2 kw for the pool pump + ? kw for my incoming EV. I can always add power walls later on but for now it'll just be solar. My backyard faces almost due south and the panels will be set on a 8x3 pattern (see attached picture).
I'll charge during the day and night along with charging at the Electrify America as I'll get 3 free years of fast charging there. I'll be grandfathered under net metering.
Current government incentives towards residential solar panels and batteries have only declined in recent years. California utility companies have also changed their rates/fees to reduce the favorability of residential solar and batteries.
Currently the economics of residential solar + battery storage provide very little ROI based on the most generous assumptions. The best argument imo for going battery storage in a home is for back up, though there are less expensive and more eco friendly ways to go about that, such as a whole house generator or even a smaller portable generator that can power the essentials (i.e. refrigerator).
I found a recent article that said for a few moments with ideal conditions, CA did indeed generate enough energy from renewables to meet their demand.
https://www.npr.org/2022/05/07/1097376890/for-a-brief-moment-calif-fully-powered-itself-with-renewable-energy
There's still 23 hours and 57 minutes of days with ideal conditions to figure out. Once we get that, then there's the days with non ideal conditions. Then stretches of days or weeks with non ideal conditions. CA is not an electric grid island, it's connected to the rest of North America (except for Texas, they're an island in terms of their grid, though they do export electricity), so just because CA's renewable supply > demand for a few moments, there's still the rest of the North America to manage. We're quite a ways off from going full renewable + stable grid.
And even if that's the direction we agree to go, it's not exactly zero emissions or ESG friendly. The mining process for the rare earth elements required to produce solar panels and batteries creates massive amounts of CO2. It also disrupts massive areas of the earth. The manufacturing process is fairly toxic as well. Much of these activities take place in developing countries with questionable labor practices. Solar panels and batteries eventually wear out, but we don't have good options for decommissioning or recycling them.
The trouble with the argument in favor of renewables and batteries is on the surface they sound plausible and win political support, but when you really dig into the economics, environmental impact, and engineering challenges, there are some serious negative impacts and problems that we do not currently have solutions for.
CA has led the charge towards adding renewables while shutting down base load generation (nuclear, fossil fuels) and peaker plants (gas). Adding demand via EV charging will exacerbate the electricity grid challenges. We'll start to see the results of these policies with grid instability soon, perhaps this summer.
I'm not saying never go renewable or buy an EV, we clearly need to manage our impact on the planet, but we have to be realistic about renewables' role in a portfolio of generation and be aware of the true environmental impact of EV & house battery manufacturing.
15-16 kilowatt-hours per day? With that size of system you should be generating about 40 kw-h per day. Or maybe you mean 15-16 megawatt-hours per year?
Yeah, I'm thinking much along the same lines. I could rationalize anywhere from 1 to 3 powerwalls, depending on assumptions. 3 PW = off grid.
See, I don't think we disagree. And when I say "incentives" I don't just mean government or monetary incentives. An increasingly unstable electric grid is, by itself, an incentive to have storage. I'm trying to make my best guess as to how it all unfolds. Should I try to wait for an increased monetary/tax installation incentive, and will I qualify, or is the 26% current incentive the best I can get, and will future increases in storage demand (due to an unstable grid) and higher costs of storage (due to limited supply) drive up costs to outweigh any increased incentives, and will future net metering rules change to favor overproduction? I think they will have to start throwing a larger bone to those who can provide power to the grid when the sun is down, and that requires storage.
The analysis paralysis has already cost me, as the price of the biggest Tesla system I would get has gone up $4k since I started thinking about it.
Yes, you are right...meta watts. My 4kw solar system in my Tustin Ranch home produces 22-24 kw per day in the summer and last year produced 6.5 meta watts so that's how I came up with 15-16 meta watts for the year and 50-60 kw per day for the Turtle Rock home (which I think is conservative as the back yard faces almost perfectly South where my panels in Tustin Ranch face southeast).
Given the uncertainty of future rates, utility company policy, and government incentives, determining the perfect time to buy a residential battery system is as clear as mud. Perhaps if you want it and can afford it, then go for it, don't look back, enjoy the peace of mind of battery back up and enjoy tinkering with all the other features. If you're not sure, maybe wait 6 months and revisit then? Good luck!
woodburyowner
Well-known member
zubs said:
So can you set the PW to store electricity only during off peak time and then during peak time, sell the energy to the grid at the higher rate?
I never use the grid - Solar during the day, and PW take over as usage becomes > solar generation. During the day I sent most of the Solar back to the grid once hte PW is regenerated. My first PGE "true-up" is next Feb, and I think if I read the arcane 10 page statement correctly I am due ~$500 so far.zubs said:
yeswoodburyowner said:
there are two ways to "sell" energy back to the grid in CA. one way is you get storage credits with your provider that are used to deduct against your metered usage. so if you "sell" energy during peak times, and use grid supply during non peak times, you come out ahead.
at end of year, any excess credits are liquidated at wholesale prices. so if you rely entirely on solar and PW and never use your banked credits you are getting a lower rate for your excess production. but you may value the energy independence more highly.
zubs
Well-known member
Apparently batteries can be run on a timer.
I do not have batteries for my solar, but was told this by the salesman.
I took my batteries budget and added more panels.
Why?....batteries degrade faster than solar panels.
I think by year 10 you are down to 70% charge....but who knows....
I do not have batteries for my solar, but was told this by the salesman.
I took my batteries budget and added more panels.
Why?....batteries degrade faster than solar panels.
I think by year 10 you are down to 70% charge....but who knows....
storage is so expensive per kwh that I really doubt it makes economic sense to get batteries just to arbitrage peak/off peak rates especially since the sun is out during much of the peak time.
it's more for people who want to be self sufficient and have protection during outages
it's more for people who want to be self sufficient and have protection during outages
fatduck said:
Also to fix energy costs. Avg PGE bill is almost $200 and rising rapidly. Couple that with stressed generation and transmission capability and fire related blackouts (even though my neighborhood has buried utilities) and the 26% federal subsidy and it just made too much sense.
The TOU plans at SCE certainly push the powerwall calculus closer to acceptance. They rape you on electricity costs right when solar generation falls off a cliff so having a reservoir to balance it all out takes the edge off. The convenience of staying powered during blackouts and not having to reset all the clocks sells it a bit more.
Financing @ 2.99% right now...with a 10 year payoff, my monthly bill would be about the same as my current electric bill (not counting the min SCE monthly charges), so not quite at breakeven, but doesn't include the tax rebate, and it would also insulate me from future price hikes.
Tax rebate not changing through 2022. I'm hoping the Powerwall V3 comes out in time to get the rebate, and without any price increases. If that pans out, I'll be in.
Financing @ 2.99% right now...with a 10 year payoff, my monthly bill would be about the same as my current electric bill (not counting the min SCE monthly charges), so not quite at breakeven, but doesn't include the tax rebate, and it would also insulate me from future price hikes.
Tax rebate not changing through 2022. I'm hoping the Powerwall V3 comes out in time to get the rebate, and without any price increases. If that pans out, I'll be in.
usctrojancpa
Well-known member
Just signed a contract with an installer through EnergySage for a 24 400w REC ProTrust panel solar system (9.6kw system) for the house that I just bought. The price was $2.60/kw which was lower than $2.69/kw for Tesla solar plus EnergySage offers a $500 rebate for an REC ProTrust panel solar system so that brings the price down to around $2.55/kw.
No storage? In the future I believe any incentives will heavily favor storage over just panels. CA is at the point of living completely off renewables during clear daylight hours, but burns a lot of fossil fuels at night, and the wide swing results in wasted energy.
You'll have to post back on your actual generation once you have some #s.
You'll have to post back on your actual generation once you have some #s.
usctrojancpa
Well-known member
daedalus said:
No storage because I'll produce more power than I use, I'll generate about 15-16 kw per year depending upon the weather. I'll probably use 6 kw for the home + 2 kw for the pool pump + ? kw for my incoming EV. I can always add power walls later on but for now it'll just be solar. My backyard faces almost due south and the panels will be set on a 8x3 pattern (see attached picture).
Attachments
How will you charge at night? My NEM for the whole year was only $190. My Tesla sucked out the PWs at night and then they recharge during the day. Solar without PWs makes little sense, especially as you start experiencing the blackouts that are currently routine up here. Remember the grid in most places isn?t set up to handle a neighborhood full of EVs.
usctrojancpa
Well-known member
OCtoSV said:
I'll charge during the day and night along with charging at the Electrify America as I'll get 3 free years of fast charging there. I'll be grandfathered under net metering.
someguy
Active member
daedalus said:
Current government incentives towards residential solar panels and batteries have only declined in recent years. California utility companies have also changed their rates/fees to reduce the favorability of residential solar and batteries.
Currently the economics of residential solar + battery storage provide very little ROI based on the most generous assumptions. The best argument imo for going battery storage in a home is for back up, though there are less expensive and more eco friendly ways to go about that, such as a whole house generator or even a smaller portable generator that can power the essentials (i.e. refrigerator).
I found a recent article that said for a few moments with ideal conditions, CA did indeed generate enough energy from renewables to meet their demand.
https://www.npr.org/2022/05/07/1097376890/for-a-brief-moment-calif-fully-powered-itself-with-renewable-energy
There's still 23 hours and 57 minutes of days with ideal conditions to figure out. Once we get that, then there's the days with non ideal conditions. Then stretches of days or weeks with non ideal conditions. CA is not an electric grid island, it's connected to the rest of North America (except for Texas, they're an island in terms of their grid, though they do export electricity), so just because CA's renewable supply > demand for a few moments, there's still the rest of the North America to manage. We're quite a ways off from going full renewable + stable grid.
And even if that's the direction we agree to go, it's not exactly zero emissions or ESG friendly. The mining process for the rare earth elements required to produce solar panels and batteries creates massive amounts of CO2. It also disrupts massive areas of the earth. The manufacturing process is fairly toxic as well. Much of these activities take place in developing countries with questionable labor practices. Solar panels and batteries eventually wear out, but we don't have good options for decommissioning or recycling them.
The trouble with the argument in favor of renewables and batteries is on the surface they sound plausible and win political support, but when you really dig into the economics, environmental impact, and engineering challenges, there are some serious negative impacts and problems that we do not currently have solutions for.
CA has led the charge towards adding renewables while shutting down base load generation (nuclear, fossil fuels) and peaker plants (gas). Adding demand via EV charging will exacerbate the electricity grid challenges. We'll start to see the results of these policies with grid instability soon, perhaps this summer.
I'm not saying never go renewable or buy an EV, we clearly need to manage our impact on the planet, but we have to be realistic about renewables' role in a portfolio of generation and be aware of the true environmental impact of EV & house battery manufacturing.
USCTrojanCPA said:
15-16 kilowatt-hours per day? With that size of system you should be generating about 40 kw-h per day. Or maybe you mean 15-16 megawatt-hours per year?
OCtoSV said:
Yeah, I'm thinking much along the same lines. I could rationalize anywhere from 1 to 3 powerwalls, depending on assumptions. 3 PW = off grid.
someguy said:
See, I don't think we disagree. And when I say "incentives" I don't just mean government or monetary incentives. An increasingly unstable electric grid is, by itself, an incentive to have storage. I'm trying to make my best guess as to how it all unfolds. Should I try to wait for an increased monetary/tax installation incentive, and will I qualify, or is the 26% current incentive the best I can get, and will future increases in storage demand (due to an unstable grid) and higher costs of storage (due to limited supply) drive up costs to outweigh any increased incentives, and will future net metering rules change to favor overproduction? I think they will have to start throwing a larger bone to those who can provide power to the grid when the sun is down, and that requires storage.
The analysis paralysis has already cost me, as the price of the biggest Tesla system I would get has gone up $4k since I started thinking about it.
usctrojancpa
Well-known member
daedalus said:
Yes, you are right...meta watts. My 4kw solar system in my Tustin Ranch home produces 22-24 kw per day in the summer and last year produced 6.5 meta watts so that's how I came up with 15-16 meta watts for the year and 50-60 kw per day for the Turtle Rock home (which I think is conservative as the back yard faces almost perfectly South where my panels in Tustin Ranch face southeast).
It's easiest to understand energy if you liken it to water. A kilowatt is a flow rate, similar to gallons per hour. A kilowatt-hour is like a "volume" of energy, similar to gallons; it's a discrete quantity of energy. If you have a flow rate of 10 gallons per hour, and the water flows for a total of 5 hours per day, then you end up with total of 50 gallons per day. Similarly, panels that generate 10 kilowatts for 5 hours per day will produce 50 kilowatt-hours per day.
someguy
Active member
daedalus said:
Given the uncertainty of future rates, utility company policy, and government incentives, determining the perfect time to buy a residential battery system is as clear as mud. Perhaps if you want it and can afford it, then go for it, don't look back, enjoy the peace of mind of battery back up and enjoy tinkering with all the other features. If you're not sure, maybe wait 6 months and revisit then? Good luck!