By definition a sunk cost is one that you cannot recover value. Your panels are an asset as you say, not a sunk cost. You can recover value from them.
Ed
Cost per mile of an EV?
- Thread starter dlundblad
- Start date
Ed
If I own an EV, I would be less worried about miles / kwh or mpg equivalent, but rather the depreciation cost, insurance cost (Tesla is 2x as much to repair so likely translate to higher insurance cost), long term battery and small production volume related repair / part cost.
You can look at Nissan Leaf, that is one expensive EV to own due to its battery design problem. You can also look at Tesla, which is also an expensive EV due to repair and insurance cost, but you get a lot more because you have a luxury car that is in high demand, although expensive to buy and depreciate (battery depreciate regardless of use, and if you don't need the range you are throwing money away). kwh? sure it cost some money but nothing in comparison to the above.
Think of it this way, people comparing a 19mpg pickup that cost $60k to a 20mpg car that cost $20k, is likely not going to worry much about the mpg difference between them.
Miles per kwh also doesn't mean much without knowing how much your kwh is at what time (3am vs 7pm) or location (at home or at work). If it is slightly more expensive to charge at work but you can double your range, buying a smaller battery, etc, you can still come out ahead (i.e. buying a used up Nissan Leaf vs a used up Chevy Volt).
You can look at Nissan Leaf, that is one expensive EV to own due to its battery design problem. You can also look at Tesla, which is also an expensive EV due to repair and insurance cost, but you get a lot more because you have a luxury car that is in high demand, although expensive to buy and depreciate (battery depreciate regardless of use, and if you don't need the range you are throwing money away). kwh? sure it cost some money but nothing in comparison to the above.
Think of it this way, people comparing a 19mpg pickup that cost $60k to a 20mpg car that cost $20k, is likely not going to worry much about the mpg difference between them.
Miles per kwh also doesn't mean much without knowing how much your kwh is at what time (3am vs 7pm) or location (at home or at work). If it is slightly more expensive to charge at work but you can double your range, buying a smaller battery, etc, you can still come out ahead (i.e. buying a used up Nissan Leaf vs a used up Chevy Volt).
I have actually built a spreadsheet to track running and charging costs for my E-Golf - have not incorporated depreciation, insurance or registration into the sheet yet but will at some point as those costs are less variable than the ongoing fueling/charging cost. If anyone wants this spreadsheet send me message and I'll be more than happy to share, would work for ICE cars as well.
Charging cost:
I live in a condo that does not have provisions for charging at home so I am relegated to public charging stations, fortunately my charging has been free at work for past few months so my cost per mile has been slowly averaging downwards.
With that being said after 4,906 miles driven since March 2, 2020 my cost per mile for charging is currently sitting at 4.59 cents per mile. With continuing free charging it goes lower and lower each charge.
Maintenance cost:
Currently I'm tracking about in line with ICE cars, I could probably reduce it by skipping the annual inspection at the dealer as it nothing more than a visual inspection of a bunch of crap but with the battery warranty going through January 29, 2025 I don't want to give VW any reason to deny battery warranty should it degrade to the 70% threshold before 2025.
Charging cost:
I live in a condo that does not have provisions for charging at home so I am relegated to public charging stations, fortunately my charging has been free at work for past few months so my cost per mile has been slowly averaging downwards.
With that being said after 4,906 miles driven since March 2, 2020 my cost per mile for charging is currently sitting at 4.59 cents per mile. With continuing free charging it goes lower and lower each charge.
Maintenance cost:
Currently I'm tracking about in line with ICE cars, I could probably reduce it by skipping the annual inspection at the dealer as it nothing more than a visual inspection of a bunch of crap but with the battery warranty going through January 29, 2025 I don't want to give VW any reason to deny battery warranty should it degrade to the 70% threshold before 2025.
As an investment, the solar panels refer to "spend money to make money."
The purchase cost of the solar project is gone; it is a sunk cost. The incremental cost of energy may change over time, but that depends on if I exceed the solar production or PGE changes their policy.
Sunk costs are excluded from future business decisions because the cost will remain the same regardless of the outcome of a decision.
The break even and future cost savings were estimated based on past usage and current electricity cost (late 2017). The break even point is accelerated as energy is consumed up to the solar generation limit and energy costs go up.
4 miles/kwh is $12/ 400 miles. Hard to beat that. EV is going to vary from 2-5 miles/kwh probably. Just like any car, efficiency varies according to the car and driver. If you go on a trip though the cost could go much higher like to 30-35 cents/kwh, or more. 12 cents though is a good rate that makes sense.
Exactly. It's called an investment. A very low risk investment. I will save tens of thousands over the 20 year expected lifetime. Minimum $25K.
Why else would anyone buy solar?
To maximize the benefit, I need to consume electricity up to the solar generation limit.
By the way, in the solar project, which included a new roof (gutters, etc) and got the 30% tax credit.
We shall have to agree to disagree on this. It seems we’ve had this discussion before. Just like Keynesian versus Friedman economics, there will be no winner.
Fair enough. I laid out my points; I am not sure you did. Or perhaps I just don't understand.
OVERKILL
$100 Site Donor 2021
Have you factored in the risk of early panel failure or degradation? What about inverter failure?
This article is a bit concerning:
Built solar assets are ‘chronically underperforming’ and modules degrading faster than expected, research finds
Solar asset underperformance continues to worsen, with projects “chronically underperforming” P99 estimates and modules degrading faster than previously anticipated, risk management firm kWh Analytics has found.
www.pv-tech.org
I like how costs became investments. A way of self persuasion that the decision was sound? In Jeff’s case, living in the bubble of Silicon Valley made it easy. For most, it is not.
If I spend $1000 on a appliance that will save me $50 a month on the electric bill that would be considered smart as the pay back time is low. If I spend $10,000 to save that same $50 then it’s not such a wise choice.
Then the issue of maintenance and repair comes into play as @OVERKILL mentioned. One good storm could lay to waste the whole project. Things will wear out or break. Maintenance has to be factored in whether it’s a solar panel system or a automobile.
If I spend $1000 on a appliance that will save me $50 a month on the electric bill that would be considered smart as the pay back time is low. If I spend $10,000 to save that same $50 then it’s not such a wise choice.
Then the issue of maintenance and repair comes into play as @OVERKILL mentioned. One good storm could lay to waste the whole project. Things will wear out or break. Maintenance has to be factored in whether it’s a solar panel system or a automobile.
That’s what happens at my FL house too! The more I use, the less the effective KWH rate. Right up until I reach 750kwh. Then the rate doubles. The sweet spot seems to be just under 750
I was looking at solar info and saw generating more than used does result in money back. I see pge does that too. What program are you on that zeros it out? If you produce more, they get to keep? This is not clear. It must be some options are available to choose from.
I don't think this is how it works. Typically if you spend the money to reduce future expense they will get depreciated, and the depreciation would be the cost per year / usage on your expense.
Once pass the depreciation limit you will likely use the opportunity cost as your "cost" per year and then the other side look at it as a "gain" you made from your investment years ago.
You usually buy insurance to cover that, or warranty. This is like asking what if your car on a loan has an engine or transmission failure. You of course would want to put that insurance or warranty cost into the calculation.Have you factored in the risk of early panel failure or degradation? What about inverter failure?
This article is a bit concerning:
Built solar assets are ‘chronically underperforming’ and modules degrading faster than expected, research finds
Solar asset underperformance continues to worsen, with projects “chronically underperforming” P99 estimates and modules degrading faster than previously anticipated, risk management firm kWh Analytics has found.
Warranted for 20 years.Have you factored in the risk of early panel failure or degradation? What about inverter failure?
This article is a bit concerning:
Built solar assets are ‘chronically underperforming’ and modules degrading faster than expected, research finds
Solar asset underperformance continues to worsen, with projects “chronically underperforming” P99 estimates and modules degrading faster than previously anticipated, risk management firm kWh Analytics has found.
States have been aware of this issue for years but low take rates gave them time before they had to do something. Obviously that's changing.
I need to look into this a little more, but I do not get money back. My cost is 32 cents per day to use the PGE grid.
If I use more than my panels generate, which many people do, then there is a true up once a year in the March/April timeframe.
I did not do the solar project for the Tesla. The Tesla does not affect the solar project cost 1 penny.
I do not know of an investment that does not incur cost. I purchased the solar project with an expected return, just like any other investment.
I agree the Silicon Valley came into play. Los Gatos is the hottest part of the valley, we get a lotta sun.
When I did substantial work to the house, I insulated the crap outta things and installed ceiling fans.
The investment was paid for in cash, so there was no interest expense. Of course, there was the opportunity cost, just like any expendature.
Our electricity costs are very high and expected to continue to rise. Staying at home this past year added unexpected energy consumption.
So you are right; the investment in the solar project was a no brainer.
Regarding maintenance, I hose 'em off. I did use the car warsh pole and car detergent after the fires. As I posted earlier, they are warranted for 20 years. The chances of something happening around here, beyond earthquakes, is pretty small anyways.
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