Does powerwall make sense without solar in 2021?

[cusetownusa]

Let me start off by saying that the Power Wall combined with Solar is the best solution by far. However, if you're like me and you haven't converted to solar yet, I think investing in a Power Wall without Solar is still a very smart investment. Here's why:

I have a separate meter for my car that's on a Time of Use plan. That Time of Use plan has worked out very well for me and for the purposes of charging my car. I pay 11 cents per kWh during off peak hours which is an extremely good rate (even when compared to solar). But that's just for my car.

I've always felt that a Time of Use plan for my home would make sense if I could find a way to store the energy during Super Off Peak hours and use it during peak hours. With the Tesla Power Wall I can do that!

Right now my home is on a tiered system where I pay 15 cents a kilowatt for Tier 1 and max out at 31 cents a kilowatt for Tier 4. I'm almost always in Tier 3 or 4 by the end of the month.

But if I switched to a Time of Use plan my cheapest rate would be 11 cents a kilowatt during Super Off-Peak hours and 36 cents during On-Peak hours.

My plan is to buy one or two of the Power Walls and have them charge up during Super Off-Peak hours and set them to power the house during peak hours. That way I'm always paying 11 cents a kilowatt regardless of the time of day. That and it would get me one step closer to a perfect Solar solution when (not if) I eventually make the switch .


Note - Please do not email me or try to sell me on Solar. I've done all the math, I've had quotes from every Solar company you can imagine (including Solar City) and I haven't switched yet for reasons that I'm not going to discuss here. Every time I tell someone that I haven't switched to Solar yet I get an ear full. I will invest in Solar sometime in the next year or two, but I'm not doing it yet for reasons that - frankly - I'm tired of explaining. So please do not message me about it, I will not respond. Thank you

So did you go through with this? I was just thinking about this very topic last night and when I googled Powerwall without solar arbitrage, this is the first thing that popped up.

I haven't done a deep dive yet by I believe for my TOU plan my off peak rate is $0.01. Not sure what my Super Peak (2pm-6pm June-August) rates are yet, but right now I pay about $0.11 when not on a TOU plan.

Not sure If I could even buy powerwalls without solar but thought there might be a possibility of using powerwalls to arbitrage my rates (charge them at night and power house during the day) and also have them as back up during a power outage.

 

[wk057]

The ROI for consistent arbitrage is pretty nonexistent even in pretty extreme cases, especially with the Powerwall costing something like $650/kWh installed, best case, these days.

Even DIY with refurbished battery modules that are significant less expensive per kWh and supporting equipment, and 100% self-consuming (so no need for grid feeding and associated costs)... it still rarely makes sense at a small scale vs other investments. You'd need something like a ~$0.50/kWh TOU delta for it to begin to be appealing, and that's not super common... nor would I expect such a thing to persist for long enough for a realistic ROI.

The energy marketplace stuff seems cool, but also seems inconsistent as a source of ROI.

If energy is so expensive in an area where battery-grid TOU arbitrage starts to seem like it might make sense... it'd probably be a better investment to just move somewhere with less ridiculous electricity costs.

 

[sunwarriors]

I'm guessing getting a PW without solar would be tough due to inventory concerns. Tesla probably won't sell it to you and 3rd parties are already limited in what they have. I have a friend waiting on a PW for over a year (has solar already).

Solar installs are also easy $$, straight forward most of the time and PWs are more work, regulation, permits, inspections, you name it.

 

[Fruitcake]

I'm guessing getting a PW without solar would be tough due to inventory concerns. Tesla probably won't sell it to you and 3rd parties are already limited in what they have. I have a friend waiting on a PW for over a year (has solar already).

Solar installs are also easy $$, straight forward most of the time and PWs are more work, regulation, permits, inspections, you name it.

>PWs are more work, regulation, permits, inspections, you name it.

That's because PWs will island/microgrid and keep your home powered during outage scenarios. Solar alone doesn't give you that. (I hear Enphase has some new technology that can island/microgrid while there is sufficient sunlight - that's some consolation, but say goodnight to that when the sun sets....)

Fruity

 

[jjrandorin]

So did you go through with this? I was just thinking about this very topic last night and when I googled Powerwall without solar arbitrage, this is the first thing that popped up.

I haven't done a deep dive yet by I believe for my TOU plan my off peak rate is $0.01. Not sure what my Super Peak (2pm-6pm June-August) rates are yet, but right now I pay about $0.11 when not on a TOU plan.

Not sure If I could even buy powerwalls without solar but thought there might be a possibility of using powerwalls to arbitrage my rates (charge them at night and power house during the day) and also have them as back up during a power outage.

(moderator note)

I moved the post you made into its own thread, because the thread you necro ressurected was from 2015, and very little from 2015 is relevant in 2021 as far as solar ROI etc is concerned.

=========================================

(regular content, not moderation)

You would need to buy this from someone other than tesla, right now.. and I also doubt that this would make sense for anyone unless the devices were basically free (which some have gotten in CA).

 

[Kandiru]

IMHO in these two scenarios:

-nuclear states with lower nocturnal rates

-rural areas where the lines are poorly maintained and power goes out with every storm

 

[cusetownusa]

Yeah. The more I look into the finances don’t seem to work. They are just too expensive right now. Also have the problem of even getting your hands on a powerwall.

The only reason I had this thought is that my utility company offers a TOU plan for EV owners and I noticed my off peak rate was only $0.01 per kWh. Was just trying to think of a way to power my house with stored energy at that $0.01 per kWh rate and have backup power for power outages.

Maybe in a few years when powerwall supply increases and prices drop it could make more sense.

 

[dandrewk]

Has anyone succeeded in purchasing the PW a la carte recently. I thought they were currently available only as a solar add on.

 

[TexacoStar5]

The only way it made sense for us was due to the batteries being subsidized by our local energy provider (Southern California Edison) due to their forced power outages during high winds.
The California Public Utility Comission dumped about $680m into an 'Equity Resilience' fund for Edison, PG&E and SDG&E to provide backup batteries for customers in high fire zones who either have water wells or medical equipment.
We have a well and had been through a few of these multi day 'public safety' outages in 2019 and 2020.
Our 2 Tesla Powerwall batteries were installed in June at a cost of $26,500.
Our developer finally got the rebate paperwork to Edison's rebate adminsitrators today, so probably another 2-3 months before we see the $26,400 check ($1,000 per KwH of rated storage)
We have been running the batteries every day to power everything in the home between the TOU peak hours of 4-9pm. The batteries then recharge after 9pm from the grid during off peak hours.
Comparing the peak demand summer months when we run the a/c a lot, the batteries are saving us about 18% compared to our prior year energy bills when we were on a non TOU rate.
Without the rebate, it would not have made sense as the ROI would be decades in our case and probably longer than the 10 year warrantied life of a Powerwall battery. We would have just continued to use a gas generator hooked in to our main supply panel during outages as before.

 

[BGbreeder]

Same here. We were on the verge of upgrading our generators (to something quieter), when the program came out. The SGIP made a big difference in the ROI for us, and we promptly ordered batteries. Those with frequent outages, medical needs, well water are obviously in a different boat compared to the typical suburban homeowner in terms of their need for power. Power is essential. And yes, we own several generators because power is essential for us, and generators have failed when needed. (Hidden metal failure) Generators are neither cheap to acquire, nor cheap to maintain nor to run, and have shorter lifetimes than most folks appreciate.

While the importance of being powered has increased during Covid due to work from home, if you can't put a dollar number on it, Powerwalls would still have a lengthy ROI for most folks, as losing food, being cold, and off line isn't costly, just uncomfortable and annoying.

On the other hand, if you do have a work from home situation, I think that the ROI begins to look more favorable as you price in the costs of directly foregone hours of work, and then less tangible costs like reputation loss due to missing meetings, etc. And if you live somewhere that freezes, like, say, Texas and places farther north, don't forget to factor in the cost of replumbing a house from frozen pipes, and all of the ensuing water damage, and how long you will be out of your house while that goes on.

I think trying to rationalize the economics of battery purchases solely by power arbitrage profits misses some other import costs and benefits. YMMV...

All the best,

BG

 

[sunwarriors]

Same here. We were on the verge of upgrading our generators (to something quieter), when the program came out. The SGIP made a big difference in the ROI for us, and we promptly ordered batteries. Those with frequent outages, medical needs, well water are obviously in a different boat compared to the typical suburban homeowner in terms of their need for power. Power is essential. And yes, we own several generators because power is essential for us, and generators have failed when needed. (Hidden metal failure) Generators are neither cheap to acquire, nor cheap to maintain nor to run, and have shorter lifetimes than most folks appreciate.

While the importance of being powered has increased during Covid due to work from home, if you can't put a dollar number on it, Powerwalls would still have a lengthy ROI for most folks, as losing food, being cold, and off line isn't costly, just uncomfortable and annoying.

On the other hand, if you do have a work from home situation, I think that the ROI begins to look more favorable as you price in the costs of directly foregone hours of work, and then less tangible costs like reputation loss due to missing meetings, etc. And if you live somewhere that freezes, like, say, Texas and places farther north, don't forget to factor in the cost of replumbing a house from frozen pipes, and all of the ensuing water damage, and how long you will be out of your house while that goes on.

I think trying to rationalize the economics of battery purchases solely by power arbitrage profits misses some other import costs and benefits. YMMV...

All the best,

BG

Totally. I have batteries and never went in thinking there was any ROI and tell others the same.

We used to run a business from home and seriously considered getting a loud generator because if we lose power, that's thousands of dollars of revenue that day. A small portable genny would pay for that in less than a day and a no brainer.

We're WFH now and if we can't do that, we'd have to actually go through various checks to go to the office and, the horror, drive to work in a gas car!

I think having some energy storage plus solar just gives anyone with it more flexibility in case of more issues and for me, I sorta just saw it as $$ I spent that I won't waste on maybe a fancier car, trip, toy, etc...

You gotta admit the fun we all had with staring at the app and you draining the batteries. That's entertainment value right there.

If this climate thing gets worst and we actually start seeing more outages here, I may get a generator to charge the batteries during cloudy days like today.

 

[h2ofun]

Totally. I have batteries and never went in thinking there was any ROI and tell others the same.

We used to run a business from home and seriously considered getting a loud generator because if we lose power, that's thousands of dollars of revenue that day. A small portable genny would pay for that in less than a day and a no brainer.

We're WFH now and if we can't do that, we'd have to actually go through various checks to go to the office and, the horror, drive to work in a gas car!

I think having some energy storage plus solar just gives anyone with it more flexibility in case of more issues and for me, I sorta just saw it as $$ I spent that I won't waste on maybe a fancier car, trip, toy, etc...

You gotta admit the fun we all had with staring at the app and you draining the batteries. That's entertainment value right there.

If this climate thing gets worst and we actually start seeing more outages here, I may get a generator to charge the batteries during cloudy days like today.

Not aware batteries can be charged from a generator?

 

[sunwarriors]

Not aware batteries can be charged from a generator?

I'm on Enphase and it's live now...

Generac "solution" generator, panels, batteries

For the medical need I have at my house, IMO, my generator provides me much better long term options than batteries. If we get into a long rainy spell, at least with my generator I know I can run it whenever I need it. We solar and batteries, I am not in the same level of control That's really...

teslamotorsclub.com

 

[el-guapin]

I'm on Enphase and it's live now...

Generac "solution" generator, panels, batteries

For the medical need I have at my house, IMO, my generator provides me much better long term options than batteries. If we get into a long rainy spell, at least with my generator I know I can run it whenever I need it. We solar and batteries, I am not in the same level of control That's really...

teslamotorsclub.com

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