EV charging

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Topic Author
RogerRabbit
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EV charging

Post by RogerRabbit »

I’ve noticed a new dynamic on fees for EV charging, curious what others may think, as well as how pricing for public EV charging stations stands to develop over the next few years.

We have two PHEVs, a 2020 Honda Clarity that charges within 2-3 hours on a standard level 2 charger for 40-50 miles of range, and a 2019 Chevy Volt that takes 4-5 hours on a level 2 charger for 55-70 miles of range. At home, we plug into 120V wall outlets overnight. Our electricity costs around $0.18/kWH, so ~$3 to fully charge either one. For the Honda is near comparable to a gallon of gas, for the Volt ~1.5 gal. Gas here currently runs around $3.20/gal.

Chargepoint and the other J1772 level 2 chargers used to be free for a few months after new install then would charge around 0.15/kWH. Recently they’ve started charging by time, anywhere from $2-3/hr on weekdays. Weekends seem to occasionally be lower at $1-2/hr. The change in pricing is new so don’t know if things spiked and fell off, or are tied to electricity costs and other factors.

Fast charge can get the Clarity most of the way there in an hour ($2-3=>$0.12-0.18/kWH) but for the Volt, which lacks fast charging, it’s now $8-12! I’m guessing the change may relate to the fast charging systems for EVs and PHEVs that can deliver more kWH per unit time, so optimal to turn around charging sessions every 1-2h?

Many area charging stations were installed under grants to local govts and non-profits to encourage more e- charging for transportation. With costs at public stations now frequently >>gallon of gas for many PHEVs, I don’t know what their present mandate has become. I guess we’ll relegate our favored Volt to the wall.

RR
snic
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Re: EV charging

Post by snic »

RogerRabbit wrote: Sat Mar 30, 2024 5:47 pm I’ve noticed a new dynamic on fees for EV charging, curious what others may think, as well as how pricing for public EV charging stations stands to develop over the next few years.

We have two PHEVs, a 2020 Honda Clarity that charges within 2-3 hours on a standard level 2 charger for 40-50 miles of range, and a 2019 Chevy Volt that takes 4-5 hours on a level 2 charger for 55-70 miles of range. At home, we plug into 120V wall outlets overnight. Our electricity costs around $0.18/kWH, so ~$3 to fully charge either one. For the Honda is near comparable to a gallon of gas, for the Volt ~1.5 gal. Gas here currently runs around $3.20/gal.

Chargepoint and the other J1772 level 2 chargers used to be free for a few months after new install then would charge around 0.15/kWH. Recently they’ve started charging by time, anywhere from $2-3/hr on weekdays. Weekends seem to occasionally be lower at $1-2/hr. The change in pricing is new so don’t know if things spiked and fell off, or are tied to electricity costs and other factors.

Fast charge can get the Clarity most of the way there in an hour ($2-3=>$0.12-0.18/kWH) but for the Volt, which lacks fast charging, it’s now $8-12! I’m guessing the change may relate to the fast charging systems for EVs and PHEVs that can deliver more kWH per unit time, so optimal to turn around charging sessions every 1-2h?

Many area charging stations were installed under grants to local govts and non-profits to encourage more e- charging for transportation. With costs at public stations now frequently >>gallon of gas for many PHEVs, I don’t know what their present mandate has become. I guess we’ll relegate our favored Volt to the wall.

RR
Just curious, do you often charge away from home? We also have 2 PHEVS but we rarely charge them anywhere other than our garage. Once in a while, if there's free charging somewhere we visit (e.g., near a restaurant or whatever), we take advantage of it, but this is rare. Kind of the whole point of PHEVs is that you can do your everyday commute on electricity from your home EVSE, without having to worry about finding a charging station when you're on a longer trip.
madbrain
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Re: EV charging

Post by madbrain »

I only charge my 2015 Volt at home. Never on the go, unless it is free, which is rare nowadays. We have two 240V/40amp Juiceboxes at home. One for the Volt and one for the Bolt.

If we didn't have solar, the cost per mile would be significantly higher for electricity than gas in the Volt.

Am EV/PHEV uses more electricity on 120V than 240V. 120V is less efficient. Installing a 240V charger- or two - will reduce both your charging time and electric bill.
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Re: EV charging

Post by Jack FFR1846 »

I don't own an EV but I watch a ton of videos of people negotiating trips and charging. I do remember specifically, Craig from Flying Wheels charging somewhere in New Hampshire at 35 cents a kWh and thought that was quite reasonable as my home cost is currently 38 cents a kWh. I do also think that you could certainly do the math on cost for gas and cost for electricity per mile as your gas price is near mine, but your electricity price is half mine. So I can tell you that electric is cheaper for you. For me, they're near equal with a Tesla Model 3 RWD kWh per mile rate. Anything more, like driving in the winter or driving a Ford lightning and gas becomes much cheaper in my area.

Perhaps keep your ear to new store opening chargers. It does seem that this happens and for some time, the chargers are free to use. And as someone else asked, why aren't you charging at home?
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MGBMartin
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Re: EV charging

Post by MGBMartin »

I don’t know if there is a question in the OPs post but…
I have an EV and I’ve never charged away from home and can’t see myself doing so any time soon.
If I had a PHEV I don’t even see the point in public charging, I’d just put enough gas in it to get me home then charge.
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vg55
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Re: EV charging

Post by vg55 »

I also have a volt. Pretty much only charge at home. Our utility provides up to 1,500 for the electrical work, another 500 for a charger, and 25/month to charge off peak. Check your utility for subsidies
Nekrotok
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Re: EV charging

Post by Nekrotok »

4 out of 4 ev/phev owners replying before me saying they just charge at home. Same for me, that makes 5/5. Why are you charging away from home OP? Most of the time it's just not worth the hassle, not even considering the cost. If you don't have the plugs at home, then install more plugs. If the range doesn't last the day, then just use gas, and consider going full ev next time around. What do you mean by "relegating" the volt to the wall? Charging at home is the preferred option, so should be "promoted" to wall charging?
FIRWYW
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Re: EV charging

Post by FIRWYW »

I play it by ear with each trip. I also have a clarity PHEV. I much prefer to drive on electric when I can (just so much quieter and better power- hence looking at next car being pure EV). I use PlugShare to look around hotels we stay at, etc. if something close to the hotel (ie rarely have used as my run for the day there and back) and reasonably priced or where we are shopping/eating out on trips, then I will charge. Vast majority in the Seattle Tacoma area has been free to 0.15/kwh. Also most hotels are cool about letting us use the 120v outlet in the garages on trips which is a full charge overnight. I have seen some hotels run as much as $6 for a gallon equivalent of range and I skip those and use gas. with clarity PHEV specifically if you like me prefer the electric in city, I have found the “EV charge mode” doesn’t rev the engine too bad if on roads without lights between 45-55mph. Overall mpg if using EV charge mode and accounting for regular charging is about the same at those speeds.
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PottedPlant
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Re: EV charging

Post by PottedPlant »

We do 99% of charging our BEV at home with a level 2 EVSE.
16¢/kWh or 5.5¢/mile.
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Re: EV charging

Post by crefwatch »

Having another car can be desirable if you make frequent trips over 150 miles. (Chevy Bolt EV owner posting.) I don't care for Elon Musk the person, but he seems to have solved most of this problem for most of his customers.

But there still are "charging deserts" near me, like Cape Cod and Maine. I'm more worried about broken chargers when I travel. For several YEARS, every charger (and the only one at some rest stops) ON the Mass Turnpike was broken.
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RogerRabbit
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Re: EV charging

Post by RogerRabbit »

Thanks for everyone’s answers.
At present we can’t run 240V into our garage per upcoming renovations. Thereafter, I agree that a level 2 home charging station will be an improvement. The other factor is that we periodically need to drive distances outside of PHEV and EV ranges, to locations where this new charging dynamic has also taken hold. This latter factor is what gives me pause to get an EV.

My broader question, perhaps not stated explicitly enough - how do folks think EV charging will evolve, in terms of expanding national infrastructure, and pricing for charging, with the corollary of needed PHEV vs EV improvements to get more of these cars on the road.

Few EVs top 500mi per charge, and are in the less affordable range; subsequent generations of PHEVs still can’t beat the 2019 Volt. Yet, I see how the Volt and other early generation PHEVs without fast charging are at a disadvantage. I read that Toyota has considerations to get the Prius Prime PHEV to 120mi range, no idea if they’ll also meet criteria for the federal rebates. However, that range for a PHEV with fast charging would be a worthwhile advancement.
Regards,

RR
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Re: EV charging

Post by crefwatch »

I've owned two Priuses, and my still has one. You are understating how revolutionary and satisfactory the Prius is, except for those who demand a Captain's Chair and a "Command seating postion" suitable for CEO chauffering. Indeed, I would be the first to say that my Bolt has rather poor "cargo capacity". But it is 10" shorter than my last Prius, which is just great for my trips to NYC.

I don't think lay person (or politicians, for that matter) can give you reliable advice for a 5-year or 10-year "trend" in on the road High-Speed EV charging. The whole thing has become political (... please, let's not start discussing that in detail!), which means that regional differences and surprise delays will unavoidably come up. So instead of thinking of yourself as a potential victim of gouging charging companies, you might think back .... unless you are too young ... to waiting in one-hour lines for gasoline, during the various oil-crises of the American past! (I'm age 72.)

To pick a less-political issue, my suburban town officials have the perverse idea that a charging station at a medium-sized strip-mall would attract "undesirables" to the town! What about the several existing gasoline stations! And these are elected councilmen who are (in fact) very "pro-business." Why would they oppose a way to get NEW customers to spend 30 minutes in a 1970's strip mall?

Your personal problem is a bit like someone who lives in a condo colony or apartment building. Your work-charging and along-the-commute-options become very important. BTW, a niece of mine is 100% satisfied with her 120 volt garage charging, because her job is within 10 miles, and she has two kids at home. Most Americans are not willing to admit or accept that the vast majority of their driving is under 10 miles. (I'm not saying you didn't express valid concerns, just making an observation.)
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Re: EV charging

Post by Wwwdotcom »

RogerRabbit wrote: Sun Mar 31, 2024 9:19 am My broader question, perhaps not stated explicitly enough - how do folks think EV charging will evolve, in terms of expanding national infrastructure, and pricing for charging, with the corollary of needed PHEV vs EV improvements to get more of these cars on the road.
It's written on the wall that public charging will either be based solely on "time parked", or "time parked" + electricity used. Obviously its up to a owner/municipality/state of a charging station to decide whether they want to subsidize electricity, but its extremely wasteful to have people be able to be parked indefinitely in an EV parking spot without being charged for it. If an non-EV wants to pay to park in a charging compatible space, so be it.
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Re: EV charging

Post by harrychan »

MGBMartin wrote: Sat Mar 30, 2024 7:51 pm I don’t know if there is a question in the OPs post but…
I have an EV and I’ve never charged away from home and can’t see myself doing so any time soon.
If I had a PHEV I don’t even see the point in public charging, I’d just put enough gas in it to get me home then charge.
Same. I can go months without charging at a public charger. The only time I use a Tesla supercharger is when we are on road trips.
This is not legal or certified financial advice but you know that already.
Valuethinker
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Re: EV charging

Post by Valuethinker »

crefwatch wrote: Sun Mar 31, 2024 11:12 am

Your personal problem is a bit like someone who lives in a condo colony or apartment building. Your work-charging and along-the-commute-options become very important. BTW, a niece of mine is 100% satisfied with her 120 volt garage charging, because her job is within 10 miles, and she has two kids at home. Most Americans are not willing to admit or accept that the vast majority of their driving is under 10 miles. (I'm not saying you didn't express valid concerns, just making an observation.)
("the wrong kind of drivers" -- I am imagining the Prius drivers of South Park, suffocating everyone with their emissions of "smug gas" :? :happy )

My guess is c 60% of American car owners park their car in their own driveway. A level 1 charger, if not a level 2, is perfectly possible then.

There was an article. Maybe Wall Street Journal?

EV users are finding "plug point" chargers quite useful. I.e. 120v Level 1. It's a mindset shift. You don't "fill er up", you just always plug your car in when it's available. Adding a few kwhr of charge each time. Your charge is seldom 100% but it's also seldom less than 20%.

This is pretty much what happens on the Canadian Prairie in winter. Plugging in to engine block heaters at offices and shopping malls - AFAIK everyone still uses them when available.

Those additional hours of charging make all the difference.

Range limitation is a valid concern, but I agree most of us probably don't realise how few times we drive more than 200 miles, say. Which is kind of the lower limit as to where most EVs are, in winter conditions, I think?
runswithscissors
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Re: EV charging

Post by runswithscissors »

Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
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Re: EV charging

Post by neilpilot »

runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Where I live, we pay about 11 cents/kWh as well, only without solar.
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Re: EV charging

Post by Valuethinker »

runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Is that 11 cents = what you do not get paid for exporting surplus power to the grid from your solar PV or your retail rate in daytime (ie assuming you have no power to export)?

Otherwise, the effective marginal cost should be 0? If your solar PV array generates surplus power in daytime & that is when you charge?
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Re: EV charging

Post by Valuethinker »

neilpilot wrote: Mon Apr 01, 2024 11:49 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Where I live, we pay about 11 cents/kWh as well, only without solar.
There's a very big range of retail power rates in the USA.

In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.

In Hawaii, where the leading source of electricity supply is fuel oil-fired generation, it can be over 50 cents/ kwhr.

Similarly in Connecticut and some other parts of New England, I believe, it can be over 30 cents/ kwhr.

OTOH it tends to be much lower in southeastern USA, and northwestern USA. Which is good in the former case, because air conditioning is so important.

State averages as of 2022

https://www.eia.gov/electricity/state/

Says average US retail rate is 12.36 c/ kwhr.
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just frank
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Re: EV charging

Post by just frank »

I've been driving PHEVs and BEVs for close to ten years, and I have used L2 public charging less than a dozen times. I never saw saving a few pennies to be worth my time. I will charge on one lot that is often full, but has a few L2 spaces (that charge the same parking fee), which will ticket non-charging vehicles parked there.

I honestly think that the economics on L2 charging are terrible... how do they make money selling for less than kWh cost at home? They don't. I think many are installed as amenities, paid for by a hotel (for guest use) or store (for customer use) or in a parking garage (where the garage still charges for the space) or in a business district where business owners or town taxpayers are footing the bill.

For this reason I see many L2 get installed, and then abandoned/broken within a couple years, and then removed a couple years after that.

I think there is a trend that these operators think they will make more money by avoiding people plugging in and sitting there all day with a full charge. AS the number of EVs has increased (about 2000% since I got my first EV), DCFCs are starting to charge idle fees. Charging L2's by time seems consistent with this trend.
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Re: EV charging

Post by madbrain »

Valuethinker wrote: Mon Apr 01, 2024 12:03 pm In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.
That's a laugh. PG&E buried a whole 73 miles of lines in 2021. 350 the next year. They have plans for 10,000 miles more, but nobody knows when that will happen. I live in a wildfire area, and it has not happened here. The reality is that the IOUs have hungry shareholders to feed.
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Re: EV charging

Post by madbrain »

just frank wrote: Mon Apr 01, 2024 12:23 pm I honestly think that the economics on L2 charging are terrible... how do they make money selling for less than kWh cost at home?
I think you meant public L2 charging.
I would say it makes sense only in locations one is likely to stay for a long time - several hours at least. Those could be things like hotels, movie theaters, hospitals, etc.

Certainly fast chargers make more sense for EVs that support them. That's not the case for all. Fast charging is only an option on many EVs. And not found on any PHEV as far as I know. Of course, PHEV drivers can just use gas for long distances.
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Re: EV charging

Post by runswithscissors »

neilpilot wrote: Mon Apr 01, 2024 11:49 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Where I live, we pay about 11 cents/kWh as well, only without solar.
This is amazing. It's about 42 cents where we are. And that's not TOU rates. That's 24-7. Gas is about $4.50/gallon here.
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Re: EV charging

Post by runswithscissors »

Valuethinker wrote: Mon Apr 01, 2024 11:59 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Is that 11 cents = what you do not get paid for exporting surplus power to the grid from your solar PV or your retail rate in daytime (ie assuming you have no power to export)?

Otherwise, the effective marginal cost should be 0? If your solar PV array generates surplus power in daytime & that is when you charge?
No, 11 cents is our LCOE. Basically the cost of electricity I pay that's generated by the PV system. It covers about 98% of our needs. The other 2% is from the grid @ 42 cents.
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Re: EV charging

Post by runswithscissors »

Valuethinker wrote: Mon Apr 01, 2024 12:03 pm
neilpilot wrote: Mon Apr 01, 2024 11:49 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Where I live, we pay about 11 cents/kWh as well, only without solar.
There's a very big range of retail power rates in the USA.

In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.

In Hawaii, where the leading source of electricity supply is fuel oil-fired generation, it can be over 50 cents/ kwhr.

Similarly in Connecticut and some other parts of New England, I believe, it can be over 30 cents/ kwhr.

OTOH it tends to be much lower in southeastern USA, and northwestern USA. Which is good in the former case, because air conditioning is so important.

State averages as of 2022

https://www.eia.gov/electricity/state/

Says average US retail rate is 12.36 c/ kwhr.
I believe the average is closer to 16 cents now. Most HCOL and VHCOL areas probably average closer to 20-25 cents. There are of course many exceptions.
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Re: EV charging

Post by Valuethinker »

madbrain wrote: Mon Apr 01, 2024 3:40 pm
Valuethinker wrote: Mon Apr 01, 2024 12:03 pm In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.
That's a laugh. PG&E buried a whole 73 miles of lines in 2021. 350 the next year. They have plans for 10,000 miles more, but nobody knows when that will happen. I live in a wildfire area, and it has not happened here. The reality is that the IOUs have hungry shareholders to feed.
It was something Severin Borenstein (who is on the California Energy Commission) said. I did not investigate its truth (or whether I understood him correctly).

The question of public rather than private ownership of utilities is here, too. Thames Water, the water & sewerage supplier for over 10m people including most of London, is owned by various big pension funds via private equity, and is teetering on bankruptcy. The papers tell me there is a plan to renationalise it.
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Re: EV charging

Post by Valuethinker »

runswithscissors wrote: Mon Apr 01, 2024 4:09 pm
Valuethinker wrote: Mon Apr 01, 2024 11:59 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Is that 11 cents = what you do not get paid for exporting surplus power to the grid from your solar PV or your retail rate in daytime (ie assuming you have no power to export)?

Otherwise, the effective marginal cost should be 0? If your solar PV array generates surplus power in daytime & that is when you charge?
No, 11 cents is our LCOE. Basically the cost of electricity I pay that's generated by the PV system. It covers about 98% of our needs. The other 2% is from the grid @ 42 cents.
Understood and thank you. LCOE usually involved a discounting, I believe, and the choice of what rate to discount at is key.

Also if you sized your solar PV array for one (larger) size because of the EV, but would have had a smaller sized array if not, then that delta could, arguably, be the capital cost of your system.

Depending on Time of Day that you charge, your marginal cost could be 0 -- if you would otherwise produce more than you need (at that time of day, and assumed no storage battery to time shift).

This is the whole trick with the combination of domestic PV and storage -- be it home battery or EV. Suddenly the economics of electricity supply are upended.
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Re: EV charging

Post by runswithscissors »

Valuethinker wrote: Mon Apr 01, 2024 4:17 pm
runswithscissors wrote: Mon Apr 01, 2024 4:09 pm
Valuethinker wrote: Mon Apr 01, 2024 11:59 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Is that 11 cents = what you do not get paid for exporting surplus power to the grid from your solar PV or your retail rate in daytime (ie assuming you have no power to export)?

Otherwise, the effective marginal cost should be 0? If your solar PV array generates surplus power in daytime & that is when you charge?
No, 11 cents is our LCOE. Basically the cost of electricity I pay that's generated by the PV system. It covers about 98% of our needs. The other 2% is from the grid @ 42 cents.
Understood and thank you. LCOE usually involved a discounting, I believe, and the choice of what rate to discount at is key.

Also if you sized your solar PV array for one (larger) size because of the EV, but would have had a smaller sized array if not, then that delta could, arguably, be the capital cost of your system.

Depending on Time of Day that you charge, your marginal cost could be 0 -- if you would otherwise produce more than you need (at that time of day, and assumed no storage battery to time shift).

This is the whole trick with the combination of domestic PV and storage -- be it home battery or EV. Suddenly the economics of electricity supply are upended.
Yes that's correct. I did the brain damage on the LCOE years ago but I had to settle on something lol. So I went with 11 cents. It did vary depending on inputs and assumptions and I I recall they were as high as 15 cents and as low as 7 cents. So I went in the middle. The performance of the PV system which includes batteries have met or exceeded my expectations so the true LCOE may be closer to 8 or 9 cents. The system is designed to accommodate 100% of our EV charging and luckily we WFH so we use the batteries in our EVs to absorb most of the excess production. It's not very often both our cars aren't home. We are also in a very year round sunny area so this helps the LCOE calculation. Arguably the PV system with batteries has been the best investment we ever made. Not just from a financial standpoint but from a convenience and peace of mind standpoint. We've had quite a few grid outages since we installed the system and never actually experienced the outage. I'm amazed more people in our area don't have systems.
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just frank
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Re: EV charging

Post by just frank »

runswithscissors wrote: Mon Apr 01, 2024 4:10 pm
Valuethinker wrote: Mon Apr 01, 2024 12:03 pm
neilpilot wrote: Mon Apr 01, 2024 11:49 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Where I live, we pay about 11 cents/kWh as well, only without solar.
There's a very big range of retail power rates in the USA.

In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.

In Hawaii, where the leading source of electricity supply is fuel oil-fired generation, it can be over 50 cents/ kwhr.

Similarly in Connecticut and some other parts of New England, I believe, it can be over 30 cents/ kwhr.

OTOH it tends to be much lower in southeastern USA, and northwestern USA. Which is good in the former case, because air conditioning is so important.

State averages as of 2022

https://www.eia.gov/electricity/state/

Says average US retail rate is 12.36 c/ kwhr.
I believe the average is closer to 16 cents now. Most HCOL and VHCOL areas probably average closer to 20-25 cents. There are of course many exceptions.
Mostly high rates are a feature of New England, California (some markets) and NYC.

There are plenty of HCOL areas outside of those places. In my area, electricity is $0.18/kWh.
chemocean
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Re: EV charging

Post by chemocean »

madbrain wrote: Sat Mar 30, 2024 7:16 pm
Am EV/PHEV uses more electricity on 120V than 240V. 120V is less efficient. Installing a 240V charger- or two - will reduce both your charging time and electric bill.
Please explain, why is a KWh charging on 120V different than a KWh charging on 240V. Is there something about the thermodynamics of a battery that I don't understand.

RE pricing. At home, I pay $0.08KWh and get about 3 miles per KWh. Therefore, the transportation costs is about $0.03/mile. At $3.00/gal, your ICE engine would need to get 100/gal to beat electric rates.
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vnatale
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Re: EV charging

Post by vnatale »

Valuethinker wrote: Mon Apr 01, 2024 12:03 pm
neilpilot wrote: Mon Apr 01, 2024 11:49 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Where I live, we pay about 11 cents/kWh as well, only without solar.
There's a very big range of retail power rates in the USA.

In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.

In Hawaii, where the leading source of electricity supply is fuel oil-fired generation, it can be over 50 cents/ kwhr.

Similarly in Connecticut and some other parts of New England, I believe, it can be over 30 cents/ kwhr.

OTOH it tends to be much lower in southeastern USA, and northwestern USA. Which is good in the former case, because air conditioning is so important.

State averages as of 2022

https://www.eia.gov/electricity/state/

Says average US retail rate is 12.36 c/ kwhr.
I am in Western Massachusetts. Currently we are at 32.4 cents per KwH. Six months prior it was 29.6 cents and the six months before then was 34.4.

As a side note .. that goes counter to all the solar companies payback projections where they have the electric rates constantly increasing with no letup.

I have extensive records on electricity rates and it's not uncommon for rates to come down for extended periods of time.
Above provided by: Vinny, who always says: "I only regret that I have but one lap to give to my cats." AND "I'm a more-is-more person."
madbrain
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Re: EV charging

Post by madbrain »

chemocean wrote: Mon Apr 01, 2024 9:25 pm Please explain, why is a KWh charging on 120V different than a KWh charging on 240V. Is there something about the thermodynamics of a battery that I don't understand.
Charging the car involves active cooling. That cooling consumes a higher percentage of the total wattage on 120V vs 240V, even if amps are equal. The cooling will need to be done for a longer period of time on 120V, also.
RE pricing. At home, I pay $0.08KWh and get about 3 miles per KWh. Therefore, the transportation costs is about $0.03/mile. At $3.00/gal, your ICE engine would need to get 100/gal to beat electric rates.
$0.08/kWh is a very low electric rate. The PG&E rate is $0.43/kWh for the first 300 kWh/month. And beyond that, $0.53/kWh. 300 kWh is very low, so, the marginal rate to charge the EV would be $0.53/kWh. I get about 3.5 miles/kWh in my Volt on average. So, the cost per mile is 15.14 cents.

The cheapest premium gas (2015 Volt requires premium) is $4.79/gallon in San Jose today. I get about 33 miles per gallon. That is 14.51 cents per mile. Slightly lower than than if I charge.

Of course, I have a $70k solar PV system, so I'm not actually paying the $0.53/kWh, and still charge the car home.
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just frank
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Re: EV charging

Post by just frank »

chemocean wrote: Mon Apr 01, 2024 9:25 pm
madbrain wrote: Sat Mar 30, 2024 7:16 pm
Am EV/PHEV uses more electricity on 120V than 240V. 120V is less efficient. Installing a 240V charger- or two - will reduce both your charging time and electric bill.
Please explain, why is a KWh charging on 120V different than a KWh charging on 240V. Is there something about the thermodynamics of a battery that I don't understand.

RE pricing. At home, I pay $0.08KWh and get about 3 miles per KWh. Therefore, the transportation costs is about $0.03/mile. At $3.00/gal, your ICE engine would need to get 100/gal to beat electric rates.
EVs have a circuit that converts input AC power to DC for charging the battery. It is designed to work well with 240V, and has a conversion efficiency greater than 90%, let's say 90-95%. The same circuit can be used to convert 120V AC to DC, but it is less efficient doing so, maybe 85-90%.
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Re: EV charging

Post by madbrain »

just frank wrote: Mon Apr 01, 2024 10:07 pm EVs have a circuit that converts input AC power to DC for charging the battery. It is designed to work well with 240V, and has a conversion efficiency greater than 90%, let's say 90-95%. The same circuit can be used to convert 120V AC to DC, but it is less efficient doing so, maybe 85-90%.
Yes . Most of the world changed to 220V for efficiency ;)

Level 1 chargers in the US are often limited to 12 amps, in order to avoid tripping a 15 amp circuit that may not be dedicated.
In addition, some cars limit the amps. On L1 my Volt charges at 8 amps by default. You can force it to 12 amps, but this has to be done every time you charge.
On L2, it charges up to 15 amps without manual intervention. The charge at 120V/8amps takes about 4x as long as 240V/15 amps.
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Re: EV charging

Post by kaseg »

madbrain wrote: Mon Apr 01, 2024 10:05 pm $0.08/kWh is a very low electric rate. The PG&E rate is $0.43/kWh for the first 300 kWh/month. And beyond that, $0.53/kWh. 300 kWh is very low, so, the marginal rate to charge the EV would be $0.53/kWh. I get about 3.5 miles/kWh in my Volt on average. So, the cost per mile is 15.14 cents.
With a PGE EV rate plan, its 0.35/kwh for off peak use (midnight to 3pm). And at least where I live, most public L2 chargers are less than this, sometimes significantly less.
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Re: EV charging

Post by madbrain »

kaseg wrote: Wed Apr 03, 2024 12:08 am With a PGE EV rate plan, its 0.35/kwh for off peak use (midnight to 3pm). And at least where I live, most public L2 chargers are less than this, sometimes significantly less.
The EV rate plans significantly raise the price at other hours, up to $0.73/kWh.

https://www.pge.com/content/dam/pge/doc ... ricing.pdf

If you have a large home, as I do, and use most of your electricity in the afternoon and evenings, as I also do, the EV charging plan will actually end up costing much more. EV owners generally have single family homes with significantly above-average consumption. Basically, the EV plan sucks. Even with 1 EV+ 1 PHEV it is better to use the ETOU-C rate, especially with solar.
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Re: EV charging

Post by TierArtz »

I'm a very happy Tesla Model Y LR owner. We almost always charge at super off peak hours on an EV plan for $0.069 (7 cents) kWh and only use superchargers while on road trips. At home, our level 2 (240w 48 amp) charger typically only takes an hour or a few to get us to our target of 80 (daily) or 100% (prior to a trip). Per the Tesla app, we've spent $957 dollars to go an estimated $21K miles; since 80% was at the super low rate, we've allegedly saved about $2700 in gasoline costs. I'll spare you all the math, but supercharging on a trip (average of 37c/kWh) does not save much over gasoline. Charging only at home is roughly 1/5th the price of gasoline/mile.
Last edited by TierArtz on Fri Apr 05, 2024 3:41 pm, edited 1 time in total.
4nursebee
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Re: EV charging

Post by 4nursebee »

RogerRabbit wrote: Sun Mar 31, 2024 9:19 am Thanks for everyone’s answers.
At present we can’t run 240V into our garage per upcoming renovations. Thereafter, I agree that a level 2 home charging station will be an improvement. The other factor is that we periodically need to drive distances outside of PHEV and EV ranges, to locations where this new charging dynamic has also taken hold. This latter factor is what gives me pause to get an EV.

My broader question, perhaps not stated explicitly enough - how do folks think EV charging will evolve, in terms of expanding national infrastructure, and pricing for charging, with the corollary of needed PHEV vs EV improvements to get more of these cars on the road.

Few EVs top 500mi per charge, and are in the less affordable range; subsequent generations of PHEVs still can’t beat the 2019 Volt. Yet, I see how the Volt and other early generation PHEVs without fast charging are at a disadvantage. I read that Toyota has considerations to get the Prius Prime PHEV to 120mi range, no idea if they’ll also meet criteria for the federal rebates. However, that range for a PHEV with fast charging would be a worthwhile advancement.
Regards,

RR
The national infrastructure is already there, built by a public company, now being offered for more vehicles, that being the evolution.
The cars you drive aren't really much of an EV and are barely around town cars for the E miles they get.
Pricing should be such that profits are made so expect higher.

I don't get the corollary PHEV/EV thing. To get more of them the road people just have to buy them. Top selling cars get 300 mi range.

Your charging situation sounds horrible though perhaps self induced. Stop charging anywhere than home. Use 120V.
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madbrain
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Re: EV charging

Post by madbrain »

TierArtz wrote: Wed Apr 03, 2024 1:50 am I'm a very happy Tesla Model Y LR owner. We almost always charge at super off peak hours on an EV plan for 0.069 c/kWh and only use superchargers while on road trips. At home, our level 2 (240w 48 amp) charger typically only takes an hour or a few to get us to our target of 80 (daily) or 100% (prior to a trip). Per the Tesla app, we've spent $957 dollars to go an estimated $21K miles; since 80% was at the super low rate, we've allegedly saved about $2700 in gasoline costs. I'll spare you all the math, but supercharging on a trip (average of 37c/kWh) does not save much over gasoline. Charging only at home is roughly 1/5th the price of gasoline/mile.
I assume you meant $0.069 / kWh, not 0.069 cents/kWh. Where are you getting that rate?
The average rate in the US is about 15 cents/kWh.

EIA lists only 2 states with < 10 cents/kWh, and they are almost at 10.

https://www.eia.gov/electricity/monthly ... epmt_5_6_a
runswithscissors
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Re: EV charging

Post by runswithscissors »

vnatale wrote: Mon Apr 01, 2024 9:34 pm
Valuethinker wrote: Mon Apr 01, 2024 12:03 pm
neilpilot wrote: Mon Apr 01, 2024 11:49 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Where I live, we pay about 11 cents/kWh as well, only without solar.
There's a very big range of retail power rates in the USA.

In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.

In Hawaii, where the leading source of electricity supply is fuel oil-fired generation, it can be over 50 cents/ kwhr.

Similarly in Connecticut and some other parts of New England, I believe, it can be over 30 cents/ kwhr.

OTOH it tends to be much lower in southeastern USA, and northwestern USA. Which is good in the former case, because air conditioning is so important.

State averages as of 2022

https://www.eia.gov/electricity/state/

Says average US retail rate is 12.36 c/ kwhr.
I am in Western Massachusetts. Currently we are at 32.4 cents per KwH. Six months prior it was 29.6 cents and the six months before then was 34.4.

As a side note .. that goes counter to all the solar companies payback projections where they have the electric rates constantly increasing with no letup.

I have extensive records on electricity rates and it's not uncommon for rates to come down for extended periods of time.
We ignore the inflation adjustment when doing the return calculation on our PV system. We just took the current rate and assumed it would stay the same over 20 years. Even with this the return was phenomenal. If the rates increase then it's just gravy. But it would be hard to argue rates won't go up over time. So unless there is zero inflation on electrical equipment and material; existing electrical infrastructure lasts forever with no degradation, there are zero storms or adverse weather events and all employees in the utility sector get zero raises for 20 years, I think it's safe to say the rates will keep going up.
runswithscissors
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Re: EV charging

Post by runswithscissors »

madbrain wrote: Wed Apr 03, 2024 12:43 am
kaseg wrote: Wed Apr 03, 2024 12:08 am With a PGE EV rate plan, its 0.35/kwh for off peak use (midnight to 3pm). And at least where I live, most public L2 chargers are less than this, sometimes significantly less.
The EV rate plans significantly raise the price at other hours, up to $0.73/kWh.

https://www.pge.com/content/dam/pge/doc ... ricing.pdf

If you have a large home, as I do, and use most of your electricity in the afternoon and evenings, as I also do, the EV charging plan will actually end up costing much more. EV owners generally have single family homes with significantly above-average consumption. Basically, the EV plan sucks. Even with 1 EV+ 1 PHEV it is better to use the ETOU-C rate, especially with solar.
That's wild. And I thought our rate at 42 cents (non TOU) were high.
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Re: EV charging

Post by madbrain »

runswithscissors wrote: Wed Apr 03, 2024 3:10 am
vnatale wrote: Mon Apr 01, 2024 9:34 pm
Valuethinker wrote: Mon Apr 01, 2024 12:03 pm
neilpilot wrote: Mon Apr 01, 2024 11:49 am
runswithscissors wrote: Mon Apr 01, 2024 11:41 am Another 100% charging at home household here. If we didn't have solar we wouldn't realize any operational savings over an ICE car. With solar we pay an effective rate of about 11 cents/kWh. Which is roughly 1/4 the cost of gas per mile.
Where I live, we pay about 11 cents/kWh as well, only without solar.
There's a very big range of retail power rates in the USA.

In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.

In Hawaii, where the leading source of electricity supply is fuel oil-fired generation, it can be over 50 cents/ kwhr.

Similarly in Connecticut and some other parts of New England, I believe, it can be over 30 cents/ kwhr.

OTOH it tends to be much lower in southeastern USA, and northwestern USA. Which is good in the former case, because air conditioning is so important.

State averages as of 2022

https://www.eia.gov/electricity/state/

Says average US retail rate is 12.36 c/ kwhr.
I am in Western Massachusetts. Currently we are at 32.4 cents per KwH. Six months prior it was 29.6 cents and the six months before then was 34.4.

As a side note .. that goes counter to all the solar companies payback projections where they have the electric rates constantly increasing with no letup.

I have extensive records on electricity rates and it's not uncommon for rates to come down for extended periods of time.
We ignore the inflation adjustment when doing the return calculation on our PV system. We just took the current rate and assumed it would stay the same over 20 years. Even with this the return was phenomenal. If the rates increase then it's just gravy. But it would be hard to argue rates won't go up over time. So unless there is zero inflation on electrical equipment and material; existing electrical infrastructure lasts forever with no degradation, there are zero storms or adverse weather events and all employees in the utility sector get zero raises for 20 years, I think it's safe to say the rates will keep going up.
The rates will go up. The question is whether it will be the fixed monthly fees, distribution fees, or generation fees. And whether your NEM scheme allows your PV system to offset the non-generation costs. I'm willing to bet a good amount of money that in 20 years, your NEM rate schedule will be a lot less favorable than it is today.
You should plan for increased net monthly costs over time, not decreases. Your PV will produce a little less every year, also as cells wear out.
runswithscissors
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Re: EV charging

Post by runswithscissors »

madbrain wrote: Wed Apr 03, 2024 4:07 am
runswithscissors wrote: Wed Apr 03, 2024 3:10 am
vnatale wrote: Mon Apr 01, 2024 9:34 pm
Valuethinker wrote: Mon Apr 01, 2024 12:03 pm
neilpilot wrote: Mon Apr 01, 2024 11:49 am
Where I live, we pay about 11 cents/kWh as well, only without solar.
There's a very big range of retail power rates in the USA.

In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.

In Hawaii, where the leading source of electricity supply is fuel oil-fired generation, it can be over 50 cents/ kwhr.

Similarly in Connecticut and some other parts of New England, I believe, it can be over 30 cents/ kwhr.

OTOH it tends to be much lower in southeastern USA, and northwestern USA. Which is good in the former case, because air conditioning is so important.

State averages as of 2022

https://www.eia.gov/electricity/state/

Says average US retail rate is 12.36 c/ kwhr.
I am in Western Massachusetts. Currently we are at 32.4 cents per KwH. Six months prior it was 29.6 cents and the six months before then was 34.4.

As a side note .. that goes counter to all the solar companies payback projections where they have the electric rates constantly increasing with no letup.

I have extensive records on electricity rates and it's not uncommon for rates to come down for extended periods of time.
We ignore the inflation adjustment when doing the return calculation on our PV system. We just took the current rate and assumed it would stay the same over 20 years. Even with this the return was phenomenal. If the rates increase then it's just gravy. But it would be hard to argue rates won't go up over time. So unless there is zero inflation on electrical equipment and material; existing electrical infrastructure lasts forever with no degradation, there are zero storms or adverse weather events and all employees in the utility sector get zero raises for 20 years, I think it's safe to say the rates will keep going up.
The rates will go up. The question is whether it will be the fixed monthly fees, distribution fees, or generation fees. And whether your NEM scheme allows your PV system to offset the non-generation costs. I'm willing to bet a good amount of money that in 20 years, your NEM rate schedule will be a lot less favorable than it is today.
You should plan for increased net monthly costs over time, not decreases. Your PV will produce a little less every year, also as cells wear out.
Agreed. We had PV on our other home and the panels degraded very little over 10+ years. The degradation was almost imperceptible... Less than 5%. So with that in mind we don't bother with calculating the degradation rate. It's just too low to be a consideration. However we are factoring a battery replacement at year 12. But we're hoping the battery tech will be significantly better (and cheaper) by that time. I am doubtful the utility will charge significant connection fees. They may go up from $15 today to maybe $50 several years downstream but if it goes well above that people will start disconnecting altogether and just using PV, battery and a generator.

Our current home is not on NEM and the utility pays peanuts (1/4 retail) for our exported power. Even if those peanuts dropped to nothing we would be fine. NEM is only important for those without battery storage.
Angel of Empire
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Re: EV charging

Post by Angel of Empire »

When everyone is charging at the same time, is it still considered "off peak"?
alfaspider
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Re: EV charging

Post by alfaspider »

madbrain wrote: Wed Apr 03, 2024 4:07 am
runswithscissors wrote: Wed Apr 03, 2024 3:10 am
vnatale wrote: Mon Apr 01, 2024 9:34 pm
Valuethinker wrote: Mon Apr 01, 2024 12:03 pm
neilpilot wrote: Mon Apr 01, 2024 11:49 am
Where I live, we pay about 11 cents/kWh as well, only without solar.
There's a very big range of retail power rates in the USA.

In PG&E territory in California, it can be over 40 cents/ kwhr - the cost of burying the power lines to protect against wildfire risk.

In Hawaii, where the leading source of electricity supply is fuel oil-fired generation, it can be over 50 cents/ kwhr.

Similarly in Connecticut and some other parts of New England, I believe, it can be over 30 cents/ kwhr.

OTOH it tends to be much lower in southeastern USA, and northwestern USA. Which is good in the former case, because air conditioning is so important.

State averages as of 2022

https://www.eia.gov/electricity/state/

Says average US retail rate is 12.36 c/ kwhr.
I am in Western Massachusetts. Currently we are at 32.4 cents per KwH. Six months prior it was 29.6 cents and the six months before then was 34.4.

As a side note .. that goes counter to all the solar companies payback projections where they have the electric rates constantly increasing with no letup.

I have extensive records on electricity rates and it's not uncommon for rates to come down for extended periods of time.
We ignore the inflation adjustment when doing the return calculation on our PV system. We just took the current rate and assumed it would stay the same over 20 years. Even with this the return was phenomenal. If the rates increase then it's just gravy. But it would be hard to argue rates won't go up over time. So unless there is zero inflation on electrical equipment and material; existing electrical infrastructure lasts forever with no degradation, there are zero storms or adverse weather events and all employees in the utility sector get zero raises for 20 years, I think it's safe to say the rates will keep going up.
The rates will go up. The question is whether it will be the fixed monthly fees, distribution fees, or generation fees. And whether your NEM scheme allows your PV system to offset the non-generation costs. I'm willing to bet a good amount of money that in 20 years, your NEM rate schedule will be a lot less favorable than it is today.
You should plan for increased net monthly costs over time, not decreases. Your PV will produce a little less every year, also as cells wear out.
It's a relatively minor impact. About .5% decrease per year. I find weather changes from year to year more noticeable. The number of hours of sun in a given year can fluctuate by a lot more than .5%.
Valuethinker
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Re: EV charging

Post by Valuethinker »

Angel of Empire wrote: Wed Apr 03, 2024 8:30 am When everyone is charging at the same time, is it still considered "off peak"?
There will be load shifting, yes.

But if peak demand is roughly twice 3am demand, then you have a lot of load growth before EVs start to stress the grid.

If you think everyone is going to try to charge their EV at 5 pm on a weekday, then there's a problem. However Time of Use rates are increasingly common, and that would militate against that. Remembering that as solar PV becomes more common, the price of electricity around mid day (wholesale) will tend towards zero.

(There's already, at least in the UK, tariffs which "lease" your EV battery back to the grid at peak hours, in return for a monthly fee).

There are variations by geography (Texas has grown *a lot*) but units (kwhr) shipped for many US electric utilities is lower now than it was in the early 2000s. So there is spare capacity there.
cmr79
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Re: EV charging

Post by cmr79 »

Valuethinker wrote: Wed Apr 03, 2024 10:32 am
Angel of Empire wrote: Wed Apr 03, 2024 8:30 am When everyone is charging at the same time, is it still considered "off peak"?
There will be load shifting, yes.

But if peak demand is roughly twice 3am demand, then you have a lot of load growth before EVs start to stress the grid.

If you think everyone is going to try to charge their EV at 5 pm on a weekday, then there's a problem. However Time of Use rates are increasingly common, and that would militate against that. Remembering that as solar PV becomes more common, the price of electricity around mid day (wholesale) will tend towards zero.

(There's already, at least in the UK, tariffs which "lease" your EV battery back to the grid at peak hours, in return for a monthly fee).

There are variations by geography (Texas has grown *a lot*) but units (kwhr) shipped for many US electric utilities is lower now than it was in the early 2000s. So there is spare capacity there.
As an example, we use roughly 7 kWh for our EV on a daily basis and have started plugging it in every day (especially over the winter, this was convenient for preconditioning). This is only 20-25% of US average daily electricity use, so it isn't really enough to move the needle outside of unusual events that affect intermittent electricity generation or increase non-EV draws, like summer heat waves and AC use.

Smart EVSEs, much like smart water heaters, actually offer an opportunity to improve grid stability by allowing utilities to have some input on charging your vehicle/heating your water when there is excess energy in the grid. With how much electricity gets wasted to supply exceeding demand at certain times, having a bunch of large batteries available (that also happen to have other utility) seems like a feature, not a bug!
madbrain
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Joined: Thu Jun 09, 2011 5:06 pm
Location: San Jose, California

Re: EV charging

Post by madbrain »

cmr79 wrote: Wed Apr 03, 2024 12:32 pm
Valuethinker wrote: Wed Apr 03, 2024 10:32 am
Angel of Empire wrote: Wed Apr 03, 2024 8:30 am When everyone is charging at the same time, is it still considered "off peak"?
There will be load shifting, yes.

But if peak demand is roughly twice 3am demand, then you have a lot of load growth before EVs start to stress the grid.

If you think everyone is going to try to charge their EV at 5 pm on a weekday, then there's a problem. However Time of Use rates are increasingly common, and that would militate against that. Remembering that as solar PV becomes more common, the price of electricity around mid day (wholesale) will tend towards zero.

(There's already, at least in the UK, tariffs which "lease" your EV battery back to the grid at peak hours, in return for a monthly fee).

There are variations by geography (Texas has grown *a lot*) but units (kwhr) shipped for many US electric utilities is lower now than it was in the early 2000s. So there is spare capacity there.
As an example, we use roughly 7 kWh for our EV on a daily basis and have started plugging it in every day (especially over the winter, this was convenient for preconditioning). This is only 20-25% of US average daily electricity use, so it isn't really enough to move the needle outside of unusual events that affect intermittent electricity generation or increase non-EV draws, like summer heat waves and AC use.

Smart EVSEs, much like smart water heaters, actually offer an opportunity to improve grid stability by allowing utilities to have some input on charging your vehicle/heating your water when there is excess energy in the grid. With how much electricity gets wasted to supply exceeding demand at certain times, having a bunch of large batteries available (that also happen to have other utility) seems like a feature, not a bug!
I have two Juice Box Pro 40 smart. They used to be smart EVSEs. Last year, Enel withdrew from the smart charging demand program. I was getting a $80/year credit for letting PG&E choose the charging times during the night. No more.
cmr79
Posts: 1355
Joined: Mon Dec 02, 2013 3:25 pm

Re: EV charging

Post by cmr79 »

madbrain wrote: Wed Apr 03, 2024 4:44 pm
cmr79 wrote: Wed Apr 03, 2024 12:32 pm
Valuethinker wrote: Wed Apr 03, 2024 10:32 am
Angel of Empire wrote: Wed Apr 03, 2024 8:30 am When everyone is charging at the same time, is it still considered "off peak"?
There will be load shifting, yes.

But if peak demand is roughly twice 3am demand, then you have a lot of load growth before EVs start to stress the grid.

If you think everyone is going to try to charge their EV at 5 pm on a weekday, then there's a problem. However Time of Use rates are increasingly common, and that would militate against that. Remembering that as solar PV becomes more common, the price of electricity around mid day (wholesale) will tend towards zero.

(There's already, at least in the UK, tariffs which "lease" your EV battery back to the grid at peak hours, in return for a monthly fee).

There are variations by geography (Texas has grown *a lot*) but units (kwhr) shipped for many US electric utilities is lower now than it was in the early 2000s. So there is spare capacity there.
As an example, we use roughly 7 kWh for our EV on a daily basis and have started plugging it in every day (especially over the winter, this was convenient for preconditioning). This is only 20-25% of US average daily electricity use, so it isn't really enough to move the needle outside of unusual events that affect intermittent electricity generation or increase non-EV draws, like summer heat waves and AC use.

Smart EVSEs, much like smart water heaters, actually offer an opportunity to improve grid stability by allowing utilities to have some input on charging your vehicle/heating your water when there is excess energy in the grid. With how much electricity gets wasted to supply exceeding demand at certain times, having a bunch of large batteries available (that also happen to have other utility) seems like a feature, not a bug!
I have two Juice Box Pro 40 smart. They used to be smart EVSEs. Last year, Enel withdrew from the smart charging demand program. I was getting a $80/year credit for letting PG&E choose the charging times during the night. No more.
Yeah, we unfortunately aren't there yet. I have a "dumb" EVSE for that reason, but I also love in an area where renewable penetration isn't high enough for it to matter much right now. Seems like something that you guys in California will need to figure out for us in the rest of the country, so if things are actually moving backwards out there, we must be even further away than I thought!
EHEngineer
Posts: 1098
Joined: Sat Feb 28, 2015 3:35 pm

Re: EV charging

Post by EHEngineer »

Valuethinker wrote: Mon Apr 01, 2024 10:43 am Range limitation is a valid concern, but I agree most of us probably don't realise how few times we drive more than 200 miles, say. Which is kind of the lower limit as to where most EVs are, in winter conditions, I think?
I have owned a model 3 for about five years. Here's how I think about range. Considering all of the following, my rule of thumb is that with current tech and charging options, normal daily driving should definitely be no more than 30% of the rated battery capacity, and ideally about 15%. If your regular commute and errands are 45 miles total, you want a car rated for 300 miles.

Above 80% is bad for the battery, so charge to 80% daily and above 80% only as required.
Below 20% is bad for 1) range anxiety, and 2) for the battery

Daily driving should be done in the middle 60%. [200 miles rated battery = 120 miles rated, for daily driving]

My tesla, and most EVs based on tests I've seen, don't get their rated efficiency in actual driving. Also, they experience vampire drain. My car is rated to consume 240 Wh/mi. It uses more like 290 Wh/mi (The screen doesn't report this because the software ignores vampire drain and most (all?) of the battery use while stopped. It definitely uses more than the screen says). Let's call it 20% less efficient than rated for real daily driving.

So, the middle 60% is more like 48% of rated range for real daily driving. [200 miles rated battery = 96 real miles for real daily driving]

Cold temps make efficiency decline further. In freezing weather it can be 50% less efficient than rated. So, the middle 60% of battery is really 30% of its rated range while driving in freezing temps. [200 miles rated battery = 60 miles for daily driving in freezing temps]

If your cold weather consumption is twice the rated value, your range anxiety may start at a higher battery percentage, further shrinking the available range that doesn't stress you out.

Additionally, you need to plan for some battery degradation with age. Over 5 years and 50,000 miles, I've lost about 5.5% of capacity. Planning for 5-10% loss is reasonable. [200 miles of rated battery = 54 miles for daily driving in freezing temps when the battery has aged]

Lastly, if instead of thinking about our normal daily mileage (median daily mileage), let's consider our 99th percentile day. That's approximately the 2nd most mileage you drove in a day during the last 3 months. How far was that, and would an EV go that far without giving you range anxiety on a cold day starting with an 80% charge and a battery with 5% degradation?
Or, you can ... decline to let me, a stranger on the Internet, egg you on to an exercise in time-wasting, and you could say "I'm probably OK and I don't care about it that much." -Nisiprius
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