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Xcel Time of Use Rates in Colorado
- Thread starter theheff
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- Mountain & Southwest USA
SageBrush
REJECT Fascism
Those with grandfathered plans should also consider that any voluntary switch out to an alternative plan may waive their right to avoid future plans.
Yes, they are all included in the billing, but they are rates that are applied to your net consumption, so they just apply to the net energy delivered by XCEL (total kWh consumed - generated kWh).
FYI, I have pretty meticulous energy consumption and production stats for the past 8+ years on my home in Colorado. I can apply the TOU rates to historical data. With no changes in habits (I have a 14.2kW PV array and a Model 3 and Volvo TC60 TD Hybrid as well as geothermal HVAC), TOU is about 5 and up to 10% higher in cost than standard residential. This is not taking into account any changes to EV charging patterns (ie charging after 9pm). The flexibility of charging whenever I want is attractive. The only thing that would sway me to TOU is if my PV surplus was somehow worth more in TOU then in residential. So does anyone know if a monthly surplus offsets more with TOU than in residential? In other words, does 5 kWh produced in shoulder rates equate to roughly 10kWh in off peak power?
I think if you currently generate more than you consume, under the two options in the current plan, you would probably be indifferent.
Option 1 (default) TOU generation for each time block is first used to offset XCEL delivered kWh for that block. Peak for peak, shoulder for shoulder, off-peak for off peak. If there are XCEL delivered kWh that are not "retired" by these block for block, then the next more valuable generated kWh is applied against the shortage (ie excess shoulder generation is used against remaining XCEL off-peak). Under this plan, the monthly excess is banked by time block for the calendar year, and can be used against future months consumption, and at year end it is all cashed out for the average annual incremental acquisition cost for the year - last year that was about $0.015/kWh.
I'd say you have little to no advantage trying to capture TOU value, since in the end, the excess is all worth the same.
Option 2 - you need to elect, and that election cannot be revoked once it's made. In this case, the generation is captured by time block, and valued the same as kWh delivered by XCEL for the same time blocks. This value goes into a bank which is used to pay for energy delivered by XCEL, so there is some value to generating in high cost times and consuming in low cost.
The problem with this option is that you will never be able convert this bank into cash. When the contract ends (you move, or shut down your system, etc) the bank is simply zeroed out, it has no cash value. So if you have and will continue to have excess generation, then you can never access the value it creates.
Sorry about the missive, but I had to talk myself through this. If anyone knows the program better than me then please feel free to correct. Thanks
Sorry, I think I replied before seeing your post. In looking at my data and calculating retrospectively, option 1 ends up costing me more on my power bill without the flexibility I currently have. Option 2, if true, may be worth it as excess PV generated during peak should offset more than 1:1 with off peak usage. Am I reading this correctly? I did apply for the program but before switching I will clarify with Xcel this critical detail. If anyone else knows the answer here, I would love to hear more detail. It's not entirely clear how consumers are supposed to know what the right choice is here as it all seems like guesswork, even with my data from the last 8 years (which most don't have).
Option 2 does allow you to offset more than 1:1. If you don't have an excess at the end of the year then that's almost certainly the option you want. I switched my solar to option 2 once I got on the TOU plan. I get credit for peak production at peak rates that then cancel out that same dollar value worth of off-peak usage later. Since there are other fees besides the rate itself I'm not sure the exact ratio of that exchange but it's definitely better than 1:1. My solar doesn't produce nearly enough to ever have a credit at the end of the year so Option 2 has no downsides for me.
The answer to that question is "it depends". That's what I tried to explain above. I don't know how much excess production you have, I don't know what it's worth under your current plan, I don't know which option under the TOU plan you would choose. I tried to describe how the TOU excess production was handled under the two options that are available, but if you always run a deficit (consumption exceeds generation) then it appears to me that if you can change your habits and use off peak energy for charging the car, you could end up ahead of the game. In this option, Energy pricing ($/kWh, ignoring all the other fees which are applied equally to all time blocks) for consumption and generation are currently:
On Peak - winter/summer $0.08880 $0.13814
Shoulder - winter/summer. $0.05143. $0.08420
Off Peak - winter/summer. $0.04440 $0.04440
So - the qualified answer to your question is - maybe. You will need to determine how much excess generation you have and when it occurs, and what it's worth under your current plan, how much of your energy usage you can shift to off peak/shoulder time, and also how you value credits in a bank for future use versus cash in hand, among other things.
BTW, as I read your last post, if your consumption for an entire month is not usually greater than consumption, do you pay XCEL for energy - not just the "service and facilities" fee - every (or most) months? If that's the case, I would say you do not have excess production, and either option under TOU could possible save you some money, but again, you will need to do some analysis to determine that.
Sorry it looks like a simple question, but there a just so many variables there is not a simple answer.
I have all the data I need to be able to calculate this: Optimus 14.190kW | Live Output
You are correct in assuming that, for the year, I only produce about 70% of consumption (obviously more in the summer).
I calculated TOU for July and for last January based upon the Peak, Shoulder, and Off Peak rates you've outlined. Unless I'm calculating incorrectly, my bill would be 5-10% higher under TOU than currently. This of course, is without any change in charging habits and also excludes the higher rate of usage with EV as I now have a Model 3 and Volvo hybrid instead of just a Volt previously. My current residential rate is $0.0546/kWh (in summer that jumps to $0.0990/kWh over 500kWh for the month). So time shifting my Model 3 charging to after 9pm saves me about $0.01/kWh used. Assuming 4 miles/kWh and 15,000 miles/year, that's a savings of about $37.50 for the year.
The only question is if I am calculating correctly from the data I have. I believe my estimates are assuming PV production to offset 1:1 kWh/kWh which I don't think is accurate. Any thoughts are appreciated.
The 1:1 assumption is not accurate if you are set up with Option 2 described above. Between that and shifting your charging to off-peak I think your calculation should show a more dramatic savings.
Edit:
The point of TOU is to encourage customers to shift their usage to off-peak times. If one is not willing or able to do that for any reason then TOU is not a good choice. A side-benefit of TOU with solar is that one can increase the effective monetary output of one's solar array by getting more credit for over-production in shoulder and peak times than one otherwise would without TOU. If one doesn't significantly over-produce during those times (and you can't shift loads outside of those times so that you have more over-production) then TOU is not a good choice.
If loads can be shifted and there is overproduction during peak times then TOU is highly likely to be a good choice.
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Using Option 2, if your PV generation exceeds the consumption during peak and shoulder times, then in the summer months, the value of the left over kWh can be used to offset about 1.5 kWh of off peak for each kWh of shoulder remaining or about 2 kWh of any peak remaining.
Then, the value of time shifting in summer should be $0.055/kWh since it looks like your base load pushes you above the 500 kWh/ month, so all car charging that's done off peak in the summer would be offsetting the higher rate.
It would probably be a good idea to confirm all this with XCEL, but I agree with @MrClown that TOU Option 2 looks pretty valuable for your situation.
TOU without solar has helped us cut our bills by nearly 30% over the past year. We recently had solar and Powerwalls installed but are still waiting for PTO. Going forward, we should really never have any peak usage, thanks to our Powerwalls. I think nearly all usage will end up being Off peak.
BTW, we ended up going with option 2 ourselves, hoping that the kWh we bank in the summer months can help offset our winter usage.
BTW, we ended up going with option 2 ourselves, hoping that the kWh we bank in the summer months can help offset our winter usage.
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I think I understand now. With some back of napkin calculations, this seems like an attractive option for me, even without Tesla charging included. Based upon the assumptions that about 1/3 of PV production is during peak hours and 60% during shoulder, I should actually end up saving over 50% of my current charges for usage for the year. Which, once you include all the fixed fees (!!), would be about a 30% savings for the year. It is very unlikely to cost me more based upon PV production being valued at TOU, which is the critical piece of the equation.
Pandamoanium
Member
I have also seen about the same reduction in my bill with this, and I don't have solar either (roof layout doesn't really work for it sadly).
Did anyone receive the recent email from Xcel concerning the changes to their Time of Use plan?
It sounds like they will be switching all residential accounts over to use ToU as smart meters are installed starting in 2021. Peak will be 3 pm to 7 pm Monday - Friday from June through September instead of 2 pm to 6 pm year-round that we have currently. Off-peak will be 10 pm until 11 am.
I don't think this is as good as what we have currently. Since installing solar and Powerwalls, I can send nearly everything back to the grid and earn credits year-round during Peak. We also send a lot back to the grid during the current Shoulder period and almost all of our usage is Off-peak, thanks to our Powerwalls. Under the proposed plan, I'll only be earning Peak credits June - September and the power we send back outside of Peak will only earn Off-peak credits instead of Shoulder credits. We just expanded our solar system by 25% last month. This could greatly affect our return on investment on our expanded 20.5 kW solar system.
There are more details on Xcel's site here. What's your opinion? Good? Bad? Depends?
It sounds like they will be switching all residential accounts over to use ToU as smart meters are installed starting in 2021. Peak will be 3 pm to 7 pm Monday - Friday from June through September instead of 2 pm to 6 pm year-round that we have currently. Off-peak will be 10 pm until 11 am.
I don't think this is as good as what we have currently. Since installing solar and Powerwalls, I can send nearly everything back to the grid and earn credits year-round during Peak. We also send a lot back to the grid during the current Shoulder period and almost all of our usage is Off-peak, thanks to our Powerwalls. Under the proposed plan, I'll only be earning Peak credits June - September and the power we send back outside of Peak will only earn Off-peak credits instead of Shoulder credits. We just expanded our solar system by 25% last month. This could greatly affect our return on investment on our expanded 20.5 kW solar system.
There are more details on Xcel's site here. What's your opinion? Good? Bad? Depends?
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