Charging and OBC discussion split from Nissan Ariya thread

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GRA is thinking of himself, and is trying to concoct an argument that his situation represents the country at large (or at least a large enough fraction that infrastructure should be built in a way that he wants.)

His situation:
No home charging
No Workplace charging
Wants cheap electricity at his convenience

Of course, even if the home next door offers him free, 10 kW charging 24/7 he would *still* not buy an EV because he has other complaints about EV cost and long distance driving convenience. And that is the real point: the GRA's of the world are not buying EVs, so it is silly to read their infrastructure preferences, let alone act on them.
 
johnlocke said:
Even if you install 6 gauge wire, you can only pull 40 amps out of a 14-50 plug for more than 3 hours by code.
Apt dwellers typically have 60 Amp feeds; most of the housing stock in the USA is around 100 - 125 Amps. I bet the the large majority of these homes struggle or are unable to even support 32 Amp EV charging.
 
SageBrush said:
johnlocke said:
Even if you install 6 gauge wire, you can only pull 40 amps out of a 14-50 plug for more than 3 hours by code.
Apt dwellers typically have 60 Amp feeds; most of the housing stock in the USA is around 100 - 125 Amps. I bet the the large majority of these homes struggle or are unable to even support 32 Amp EV charging.

It would depend on wether their heat and hot water are gas or electric. We have a 100 amp service. We have two charge stations. A 12 amp 240 volt exterior clipper creek and a 32 amp 240 volt in garage unit. That would not be possible if we didn’t have natural gas. Well, unless we went with solar and on-site storage.
 
webeleafowners said:
SageBrush said:
johnlocke said:
Even if you install 6 gauge wire, you can only pull 40 amps out of a 14-50 plug for more than 3 hours by code.
Apt dwellers typically have 60 Amp feeds; most of the housing stock in the USA is around 100 - 125 Amps. I bet the the large majority of these homes struggle or are unable to even support 32 Amp EV charging.

It would depend on wether their heat and hot water are gas or electric. We have a 100 amp service. We have two charge stations. A 12 amp 240 volt exterior clipper creek and a 32 amp 240 volt in garage unit. That would not be possible if we didn’t have natural gas. Well, unless we went with solar and on-site storage.
Exactly. And in a perverse turn of events, the less expensive and/or older the house, the more likely it has cheap electric appliances and a small capacity electric panel.
 
johnlocke said:
GRA said:
johnlocke said:
Unless you hardwire the L2 charger, you're limited to a 50 amp plug. furthermore if you are drawing current for more than 3 hours, you're limited to 40 amps max out of that plug or 9.6 KW. There are plug-in chargers that can do that. Now assuming a100KH battery and 80% discharge (90%-10%), 90% efficiency and 240VAC, you need 9.5 hours to charge back to 90%. If you use a 32A charger instead then you're looking at 11.5 hours. Either way, plug it in when you get home and you'll be charged up in the morning. And who says you have to have a full charge in the morning anyway? Won't 60-70% be enough for the day? And how often are likely to discharge to 10% or less.

DCFC charging rates might be a problem if you're pressed for time, but overnight charging with a typical L2 isn't a problem.


I disagree that you'll want to take that much time to charge, as utilities more and more go to ToU rates with restricted hours. SDG&E only has a 6 hour super off-peak window, 12M - 6a.m. I agree that 40A (so that you can use a NEMA 14-50 on a 50A circuit) is reasonable for rental property, or anyone who wants to have the option of portability provided by using a plug-in EVSE. Personally, I'd routinely charge no more than 50-60% (20 or 30% - 80%) and except in extreme circumstances would normally limit myself to 70% max. (20-90%). I've been considering what I'll recommend to my landlord when the time comes, and am thinking that I'd suggest a 60A circuit terminating in a NEMA 14-50 receptacle. That way the occupant can always choose to hardwire it instead for 48A, a simple swap out rather than re-wiring.

Public L2 is a different matter, as those won't need portability, and you want people to be able to get a substantial charge in 2-3 hours (dinner and a movie, say) as well as overnight use.

Restricting to 30-32A or even 40A assumes that packs won't need to continue to grow beyond 100kWh so that they can provide full replacement for fossil-fueled ICEs, and that's extremely unlikely (barring [PH]FCEVs), so 48A or better is what we should aim at. Initially the public ones may be shared some or all the time, but eventually you'll need full power for each EVSE.
Even if you install 6 gauge wire, you can only pull 40 amps out of a 14-50 plug for more than 3 hours by code. The breaker can't be more than 50A if there's a 14-50 plug. Do you really think the landlord is likely to install larger gauge wire on the premise that someone in the future might want to hardwire a charger? He might let them pay for that improvement if they were lucky. If you are talking about destination chargers, why would you expect them to provide you with more than 40 amps? It's a convenience feature. In 3 hours you could suck down 20 KWH anyway. If your utility limits your lowest cost hours, then you might need to charge on two consecutive nights instead of one. If you need to charge faster than that, DCFC is the answer, not 11KW L2.

As far as batteries being larger than 100KWH in the future, maybe for pickups and delivery vans but not for cars. 300-400 mi range is more than adequate and carrying the extra weight for capacity that you don't use is detrimental to efficiency. Delivery vehicles will have charging stations at their home base capable of charging them at whatever speed the manufacturer deems optimal for their use. Semi's will have DCFC chargers. Pickups will be likely charged overnight for most business use. People who haul trailers will be the oddball case. Likely charging overnight for normal use and DCFC when hauling long distances. People tend to buy pickups for specific needs, so a range of battery sizes and hauling capacities are likely.
Actually from what I understand it's not the outlet nor wiring that the 80% rule comes into play but rather the breaker that will overheat if you exceed 80% for more than 3hrs. In this case, running a 60a breaker to a 50a outlet with 6g wiring should be fine as long as you don't exceed 48a continuously but the rub would be pulling more than 50a for a shorter period of time. The breaker wouldn't trip but you'd be overstressing the outlet and wiring. Whitney would probably know for sure if this scenario would be OK but I'd be inclined to say it wouldn't by code. Now they make continuous rated breakers where you could continuously pull 50a from a 50a breaker but they seem to be very rare and I personally haven't seen one for such high currents although they may very well be available.
I for one am in favor of high current L2 charging and am really bummed our pre-ordered PHEV(with a larger16kwh battery) will only come with a measly 3.3kw OBC, a step back from our 6.6kw Leaf but I wasn't willing to spend $5k+ extra to get the top of the line model and even then have to order the top of the line package upgrade to get not only the upgraded OBC but also tons other things I didn't want. I personally think 32a(7.7kw) is probably the best compromise for portable(pluggable) EVSEs, maybe 48a(11.5kw) if you wanted to use a 14-60 outlet and reserve faster L2 charging to hardwired EVSE.
 
jjeff said:
In this case, running a 60a breaker to a 50a outlet with 6g wiring
Negative. NEC 210.21(B)(1) "Single Receptacle on an Individual Branch Circuit. A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit."

Cheers, Wayne
 
wwhitney said:
jjeff said:
In this case, running a 60a breaker to a 50a outlet with 6g wiring
Negative. NEC 210.21(B)(1) "Single Receptacle on an Individual Branch Circuit. A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit."

Cheers, Wayne

I thought that might be the case. Just thinking it through and I never really see 240v outlets sharing a circuit, especially a high amperage circuit like were talking about but to comply with code could one put 2 individual 50a outlets on that 60a breaker? You'd really only ever use the one but that would get around the code you cited? again knowing you should never exceed the 50a outlet rating, you'd need an adjustable or fixed 48a max EVSE.
 
jjeff said:
could one put 2 individual 50a outlets on that 60a breaker?
A separate section limits circuits with more than one receptacle to having each receptacle match the branch circuit size, with the clarification that 15A receptacles match both 15A and 20A circuits (as they are listed for 20A feed through) and that 50A receptacles match both 40A and 50A circuits (as there are no NEMA 40A receptacles).

Cheers, Wayne
 
SageBrush said:
GRA said:
Sure, 7.2 is an improvement over 3.84, but then pack size has increased by an even greater %
But daily miles driven do not increase proportionally with pack size increase. :eek:

I find it amusing that you trumpet PHEV in one post, and bemoan 7.2 kW in another. Would the real GRA step forward ?


Of course daily miles driven don't increase with pack size, although there's often a correlation - if you've got a longer commute, you're going to need a car with a bigger battery, aren't you? As I've pointed out, what does increase given the same commute is the number of days you can go between charges. People who have dedicated charging at home or work won't much care, but those who rely on public charging at least until it's everywhere will care, and that's at least 44% of U.S. households as of a few years ago per Plug-in America. It's the people who live in high-density urban areas who typically have no way to charge at home, and where air pollution and GHG emissions are concentrated, we need to provide means to make a transition to ZEVs viable for and acceptable to them.

BTW, I've never 'trumpeted' PHEVs, I see them as one current means of reducing GHG emissions that could be acceptable for mass market consumers who need cars that can fully replace the capability of their ICEs now, given the lack of range, charging speed, longevity and infrastructure, and high price of current BEVs. Improve BEVs in those areas and the need for PHEVs reduces. Whether it ever goes to zero or we instead ultimately adopt a mix of BEVs, PHFCEVs and bio-fuels to meet the full spectrum of vehicle needs depends on relative developments in all three techs, plus consumer acceptance.
 
Third try at this. Finger problems plus one disappeared.


johnlocke said:
GRA said:
johnlocke said:
Unless you hardwire the L2 charger, you're limited to a 50 amp plug. furthermore if you are drawing current for more than 3 hours, you're limited to 40 amps max out of that plug or 9.6 KW. There are plug-in chargers that can do that. Now assuming a100KH battery and 80% discharge (90%-10%), 90% efficiency and 240VAC, you need 9.5 hours to charge back to 90%. If you use a 32A charger instead then you're looking at 11.5 hours. Either way, plug it in when you get home and you'll be charged up in the morning. And who says you have to have a full charge in the morning anyway? Won't 60-70% be enough for the day? And how often are likely to discharge to 10% or less.

DCFC charging rates might be a problem if you're pressed for time, but overnight charging with a typical L2 isn't a problem.


I disagree that you'll want to take that much time to charge, as utilities more and more go to ToU rates with restricted hours. SDG&E only has a 6 hour super off-peak window, 12M - 6a.m. I agree that 40A (so that you can use a NEMA 14-50 on a 50A circuit) is reasonable for rental property, or anyone who wants to have the option of portability provided by using a plug-in EVSE. Personally, I'd routinely charge no more than 50-60% (20 or 30% - 80%) and except in extreme circumstances would normally limit myself to 70% max. (20-90%). I've been considering what I'll recommend to my landlord when the time comes, and am thinking that I'd suggest a 60A circuit terminating in a NEMA 14-50 receptacle. That way the occupant can always choose to hardwire it instead for 48A, a simple swap out rather than re-wiring.

Public L2 is a different matter, as those won't need portability, and you want people to be able to get a substantial charge in 2-3 hours (dinner and a movie, say) as well as overnight use.

Restricting to 30-32A or even 40A assumes that packs won't need to continue to grow beyond 100kWh so that they can provide full replacement for fossil-fueled ICEs, and that's extremely unlikely (barring [PH]FCEVs), so 48A or better is what we should aim at. Initially the public ones may be shared some or all the time, but eventually you'll need full power for each EVSE.

Even if you install 6 gauge wire, you can only pull 40 amps out of a 14-50 plug for more than 3 hours by code. The breaker can't be more than 50A if there's a 14-50 plug.


Yes, wwhitney cleared that up; I thought it was okay to install a lower-amp receptacle on a higher-rated circuit, as (barring DIY) any appliance using a 14-50 plug would be 50A or less (40A for an EVSE).


johnlocke said:
Do you really think the landlord is likely to install larger gauge wire on the premise that someone in the future might want to hardwire a charger? He might let them pay for that improvement if they were lucky.


It it affects the desirability of the property, they might. Alternatively, it will be required by code in the future. Given the current illegality of installing a lower-rated receptacle on a dedicated higher-amp circuit, it likely won't happen (unless the code is changed). As for who pays, I've certainly considered paying for a higher-amp circuit than the landlord wants to when the time comes, just so I can buy an EVSE with a 14-50 for emergency use on trips. Whether I do so will depend on how road-trip DCFC infrastructure develops in the meantime. Note that given the intermittent use my car gets, I could get by with just L1 plus DCFC for emergencies. People with greater daily usage couldn't.



johnlocke said:
If you are talking about destination chargers, why would you expect them to provide you with more than 40 amps? It's a convenience feature. In 3 hours you could suck down 20 KWH anyway.


You're correct, it _is_ a convenience feature, and maximizing convenience is necessary to get consumer acceptance. Note, most public L2s will be 208 not 240V, and 208V/48A is 9.984kW, only 4% more than 240/40 so essentially the same. 208/40 is about 8% more than 240/32, so again practically the same.


johnlocke said:
If your utility limits your lowest cost hours, then you might need to charge on two consecutive nights instead of one. If you need to charge faster than that, DCFC is the answer, not 11KW L2.


Again, convenience. We're not talking about people with guaranteed parking/charging spots.

In that vein, I'm reminded of a former girlfriend who, when living in San Francisco, often had to park in bus stops because she was unable to find legal street parking within several blocks of her apt., and she didn't feel safe walking that far at night (working swing shift). She'd hopefully hear her alarm a few hours later and move her car when the early birds went to work before the buses started running. She sometimes didn't, and had a couple grand in parking fines when I met her.

There are far more on-street parking spaces than there'll be chargers for a long time to come. Others may not be able to find a convenient place to charge two nights in a row, or you may have to share chargers on a schedule in a MUD off-street setting. Eventually they'll be enough chargers for everyone, but that's decades away.


johnlocke said:
As far as batteries being larger than 100KWH in the future, maybe for pickups and delivery vans but not for cars. 300-400 mi range is more than adequate and carrying the extra weight for capacity that you don't use is detrimental to efficiency.


We disagree on your first point. If batteries were capable of 300-400 highway miles at realistic speeds with reserves adequate to get them to the next charging station beyond the intended one, plus allowances for hotel loads, could be repeatedly charged in the time it takes to eat at a fast food restaurant
and do the same distance again, and would provide that range for the life of the car, then we would agree. They can't yet. To take one example, the Ionic 5 can charge from 20-80% in 15 minutes, but per Bjorn Nyland its full range (100%-0%) at 75 mph is only 180 miles (hotel loads unstated). 60% of 180 is 108 miles, and plenty of western freeways have speed limits or are moving at 80mph. Do you want to be forced to stop every 1:00-1:20 to charge for 15 minutes? Are DCFCs even spaced that closely together on the route?

If so, is 20% enough of a reserve to get you to the next FC beyond that? Are you willing to use a wider SoC range regularly, knowing that it will cause accelerated battery degradation? I mentioned in another topic, the best-selling ICE cars in the U.S. have (EPA combined) ranges between 450-500 miles, so 400+ Hwy. Manufacturers aren't providing that range if there's no consumer demand for it, and unlike BEVs you can if you wish repeatedly use all of it without affecting the long-term viability of the car.

On your second point, I've been making the weight/efficiency (along with stretching the battery supply) argument in favor of fossil-fueled PHEVs -> PHFCEVs and/or syn- or bio-fueled PHEVs in the PHEV topic, with much pushback from battery-only advocates. Please feel free to support my argument there. :D


johnlocke said:
Delivery vehicles will have charging stations at their home base capable of charging them at whatever speed the manufacturer deems optimal for their use.


No argument from me, I'm talking about private not commercial vehicles, although the same basic consideration applies. Unless you've got guaranteed charging, you're not going to switch.


johnlocke said:
Semi's will have DCFC chargers


For regional distribution, but the payload weight and time penalties call for other techs for long-haul, even more than is the case with private vehicles. Current BEV semis apparently have about a 25% payload penalty vs. diesels at longer ranges, and that's after the extra 2,000 GVWR boost (82 vs. 80k) they're allowed as AFVs, to the detriment of our roads. That's not going to be acceptable unless they're restricted to hauling fluff commodities.


johnlocke said:
Pickups will be likely charged overnight for most business use. People who haul trailers will be the oddball case. Likely charging overnight for normal use and DCFC when hauling long distances. People tend to buy pickups for specific needs, so a range of battery sizes and hauling capacities are likely.


Again, while trailer-pulling is the most demanding case, plenty of people take road trips without pulling trailers. I don't see many trailers in national parks. NRAs are another matter.
 
wwhitney said:
jjeff said:
In this case, running a 60a breaker to a 50a outlet with 6g wiring
Negative. NEC 210.21(B)(1) "Single Receptacle on an Individual Branch Circuit. A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit."

Cheers, Wayne


Thanks, couldn't remember for sure and my knowledge is a few decades out of date in any case, but thought you could put a lower amperage receptacle on a higher amp. circuit provided the wiring was for the higher amperage. So, 50A max. circuit if there's a NEMA 14-50, for 40A charging.
 
SageBrush said:
johnlocke said:
Even if you install 6 gauge wire, you can only pull 40 amps out of a 14-50 plug for more than 3 hours by code.
Apt dwellers typically have 60 Amp feeds; most of the housing stock in the USA is around 100 - 125 Amps. I bet the the large majority of these homes struggle or are unable to even support 32 Amp EV charging.
Average electrical usage in the US is 800-900 KWH/month. That's 30 KWH per day or 1.25 KWH per hour. A little over 5 amps at 240vac. lots of room for a 32 amp load even on a 60 amp circuit. As a reference, I run a 2700 sf house (all electric except for the stove) off a 100 amp breaker. I use 32000 KWH annually or about 90 KWH per day. Highest peak demand ever was 21KWH/H but normal peak demand is around 13-15 KWH/H. Average demand is around 4-5 KWH/H. The spa and instant demand water heater are on separate breakers from the main house for load shedding during power outages but are included in the total power usage.
 
SageBrush said:
GRA is thinking of himself, and is trying to concoct an argument that his situation represents the country at large (or at least a large enough fraction that infrastructure should be built in a way that he wants.)

His situation:
No home charging
No Workplace charging
Wants cheap electricity at his convenience


Un huh, which per the Plug-in America survey I've mentioned describes 44% of America's 125 million or so households, which to my mind represents 'a large enough fraction'. Even of the 56% who can charge at home, some % only have L1, e.g. the house my grandparents bought new in Oakland in 1941, which subsequently passed to my dad and then me before I sold it, had a service entrance with 2 30A glass fuses wired for 120V only, and 4 15A branch circuits also with glass fuses. Like most houses in the Bay Area built probably well into the '60s if not later, cooking, heating and laundry were gas.

I've also previously described the results of some of the informal surveys I've done of some of the apartment buildings in my current neighborhood, which either lacked any circuits in their parking areas at all, or else had a few 5-15 or 5-20 receptacles covering just a small fraction of the total parking spaces. You know, the kind of households who make up a large % of that 44%. But I guess you consider them beneath your notice - they don't describe your situation, therefore they're unimportant. Thankfully, our state and many of our local goverments think differently.



SageBrush said:
Of course, even if the home next door offers him free, 10 kW charging 24/7 he would *still* not buy an EV because he has other complaints about EV cost and long distance driving convenience. And that is the real point: the GRA's of the world are not buying EVs, so it is silly to read their infrastructure preferences, let alone act on them.


Unless of course you think it important to convert them from fossil fuels to BEVs, in which case you have to listen to and meet their requirements. Ot course, if you can simply compel people to switch and force them to live with what they see as an inadequate replacement then no worries, but we haven't quite reached that stage yet.
 
johnlocke said:
SageBrush said:
Apt dwellers typically have 60 Amp feeds; most of the housing stock in the USA is around 100 - 125 Amps. I bet the the large majority of these homes struggle or are unable to even support 32 Amp EV charging.
Average electrical usage in the US is 800-900 KWH/month. That's 30 KWH per day or 1.25 KWH per hour. A little over 5 amps at 240vac. lots of room for a 32 amp load even on a 60 amp circuit.
Average consumption does not tell you anything about whether an electrical panel can support 32 Amp EV charging. You have to add up your breakers and then apply a fudge factor that estimates concurrent operation, presuming that there is space in the panel in the first place.

The problem with measuring peak loads, at least in terms of the electrical utility, is that they average loads over 15 or 30 minutes. They don't care about transient peaks that last a few seconds, but your electrical panel does. As one example, my fridge averages 40 watts but each time the compressor kicks in power rises to about 1900 watts for a few seconds. Below is a short list of common 240v electric appliances and typical breakers:

Electric water heater: 30 Amps
Demand water heater: 50 - 60 Amps
Electric range: 40 - 50 Amps
A/C: 40 Amps
Electric furnace: 80 - 100 Amps
Electric dryer: 30 Amps

It is assumed that air heating and cooling are not going on at the same time, but otherwise load calcs are something along the lines of
0.4 * (Load - 10 kW) + 10 kW.

In terms of Amps for 240v loads it would be
0.4 * (breaker_total - 40) + 40

So e.g., a demand water heater + electric range + electric furnace + electric dryer = 50+50+80 + 30 = 210 Amps of breakers. The load calc just for these devices is
0.4 * (210 - 40) + 40 = 108 Amps

A more modest electric home with electric range + electric dryer + A/C + electric water tank = 50 + 30 + 40 + 30 = 150 Amps of breakers. The load calc for these devices is
0.4 * (150 - 40) + 40 = 84 Amps.

And these are just the major loads. A typical home has another 10 - 20 breakers of 15 Amps each at 120 volts
 
GRA said:
Unless of course you think it important to convert them from fossil fuels to BEVs, in which case you have to listen to and meet their requirements. Ot course, if you can simply compel people to switch and force them to live with what they see as an inadequate replacement then no worries, but we haven't quite reached that stage yet.

Time needs to be considered. Yes, there might be a problem starting a decade or more in the future.

If BEV sales continue to double roughly ever 2.5 years, then sometime around 2030 BEV sales will be the majority of new cars. If the lifetime of cars on the road continues at 20+ years and that's true for both BEVs and ICEs, then sometime around 2050 BEVs will the majority of cars on the road.

Apartment dwellers usually don't buy new cars. So in twenty years, give or take 5-10 years, this problem needs to be solved. Solving it now likely leads to unwanted, unused and decaying infrastructure.

If this is market forces only, then higher end units will get charging first (which is already happening) and the units where almost everyone takes the bus or drives a 40 year old junker will get charging last. Why would a landlord install charging? Hint, the landlord doesn't get to compel tenants to stay.

Notice that the used car and rental markets will drive the change, not any "compel people". Yet there is likely a point where subsidies and/or mandates and/or taxes might make the transition better. Markets can be reactive, and not forward looking.

Unless your goal is to prevent the spread of electric cars, then forcing charging to be installed where it is unwanted, will be unused and will decay isn't useful.
 
WetEV said:
Time needs to be considered. Yes, there might be a problem starting a decade or more in the future.

Apartment dwellers usually don't buy new cars. So in twenty years, give or take 5-10 years, this problem needs to be solved. Solving it now likely leads to unwanted, unused and decaying infrastructure.

Unless your goal is to prevent the spread of electric cars, then forcing charging to be installed where it is unwanted, will be unused and will decay isn't useful.

Exactly
 
Kind of way off topic here, aren't we? That said, here's my 2 cents...

I look at the market potential based on best fit for purpose on the current crop of EVs, and notice that roughly 2/3rd of American households own their own place and could presumably charge at home some very large fraction of the time, say 85-100%. I'm not certain, but I'm inclined to think the vast majority of those households are well-enough off to also have 2 cars. If just half of these households don't need 2 cars capable of cross-country trips, that would imply about a third of households could not only justify but likely strongly benefit from going electric right now, at least with their "second" car.

Since the major advantage of an EV lies mostly in their low cost of operation, this suggests that take up could indeed accelerate very quickly once the word gets out, so to speak. I'm also inclined to believe that take up beyond that use case will tend to tail off looking forward. I don't see folks wholesale abandoning ICE vehicles across the board any time soon, but circumstances will change with market acceptance of EVs, and I'd be happy to be wrong on that point.

Maybe I just listen to all the guys revving the engines on their giant trucks in the neighborhood too much... there are emotional attachment and psychological identity factors to consider. Those factors are notoriously difficult and resilient to change.
 
WetEV said:
GRA said:
Unless of course you think it important to convert them from fossil fuels to BEVs, in which case you have to listen to and meet their requirements. Ot course, if you can simply compel people to switch and force them to live with what they see as an inadequate replacement then no worries, but we haven't quite reached that stage yet.

Time needs to be considered. Yes, there might be a problem starting a decade or more in the future.

If BEV sales continue to double roughly ever 2.5 years, then sometime around 2030 BEV sales will be the majority of new cars. If the lifetime of cars on the road continues at 20+ years and that's true for both BEVs and ICEs, then sometime around 2050 BEVs will the majority of cars on the road.


Assuming BEV sales actually do double every 2.5 years, and they aren't doing that here yet. Sure, time needs to be considered. Sometime around 2050 will probably be far too late, which is why more and more states are panning to ban sales of them by 2030 or 2035.


WetEV said:
Apartment dwellers usually don't buy new cars. So in twenty years, give or take 5-10 years, this problem needs to be solved. Solving it now likely leads to unwanted, unused and decaying infrastructure.


Well, no, because used BEVs (which had inadequate range even when new) with seriously degraded batteries will be of even less use to apartment dwellers, especially if they can't charge them quickly. Maybe we'll develop batteries that degrade far more slowly; California's draft plan seemed to assume we could mandate that by 2026 (i.e. requiring warrantying 80% capacity at 15 years), which would be an interesting trick. You've got to make used BEVs useful to them much earlier in the cycle not 10-12 years down the road, and that requires infrastructure plus longer ranges when new, which is why California is emphasizing putting a large % of the additional 1M+ chargers the state estimates we'll need by 2030 at MUDs plus public areas (L2 and DCFCs at the latter), especially in lower-income areas that have the worst pollution.


WetEV said:
If this is market forces only, then higher end units will get charging first (which is already happening) and the units where almost everyone takes the bus or drives a 40 year old junker will get charging last. Why would a landlord install charging? Hint, the landlord doesn't get to compel tenants to stay.


See above. Charging facilities will have to be mandated for most rental property, because most landlords get no benefit, and the tenant isn't going to pay.



WetEV said:
Notice that the used car and rental markets will drive the change, not any "compel people". Yet there is likely a point where subsidies and/or mandates and/or taxes might make the transition better. Markets can be reactive, and not forward looking.


See above.



WetEV said:
Unless your goal is to prevent the spread of electric cars, then forcing charging to be installed where it is unwanted, will be unused and will decay isn't useful.


Uh huh, and the whole reason for mandating charging and ensuring adequate battery life/range is to make BEVs a viable option for people who have much less choice in where they live or what cars they buy. California is also providing extra subsidies for PEV purchases and charging infrastructure in low-income communities with poor air quality, who also tend to drive the oldest and dirtiest cars. While I'm against direct to consumer subsidies in general, if you're going to subsidize anyone to buy BEVs it should be people at the lower end of the income scale, not the well-off who don't need it. In any case, as another poster has noted we've wandered far off-topic here and we've had this argument before, so I'll close by re-iterating that I consider the Ariya's OBC power inadequate, both as to its competition and the need, for the reasons I've stated.
 
SageBrush said:
johnlocke said:
SageBrush said:
Apt dwellers typically have 60 Amp feeds; most of the housing stock in the USA is around 100 - 125 Amps. I bet the the large majority of these homes struggle or are unable to even support 32 Amp EV charging.
Average electrical usage in the US is 800-900 KWH/month. That's 30 KWH per day or 1.25 KWH per hour. A little over 5 amps at 240vac. lots of room for a 32 amp load even on a 60 amp circuit.
Average consumption does not tell you anything about whether an electrical panel can support 32 Amp EV charging. You have to add up your breakers and then apply a fudge factor that estimates concurrent operation, presuming that there is space in the panel in the first place.

The problem with measuring peak loads, at least in terms of the electrical utility, is that they average loads over 15 or 30 minutes. They don't care about transient peaks that last a few seconds, but your electrical panel does. As one example, my fridge averages 40 watts but each time the compressor kicks in power rises to about 1900 watts for a few seconds. Below is a short list of common 240v electric appliances and typical breakers:

Electric water heater: 30 Amps
Demand water heater: 50 - 60 Amps
Electric range: 40 - 50 Amps
A/C: 40 Amps
Electric furnace: 80 - 100 Amps
Electric dryer: 30 Amps

It is assumed that air heating and cooling are not going on at the same time, but otherwise load calcs are something along the lines of
0.4 * (Load - 10 kW) + 10 kW.

In terms of Amps for 240v loads it would be
0.4 * (breaker_total - 40) + 40

So e.g., a demand water heater + electric range + electric furnace + electric dryer = 50+50+80 + 30 = 210 Amps of breakers. The load calc just for these devices is
0.4 * (210 - 40) + 40 = 108 Amps

A more modest electric home with electric range + electric dryer + A/C + electric water tank = 50 + 30 + 40 + 30 = 150 Amps of breakers. The load calc for these devices is
0.4 * (150 - 40) + 40 = 84 Amps.

And these are just the major loads. A typical home has another 10 - 20 breakers of 15 Amps each at 120 volts
My point still stands. Even with my large house and numerous loads I still manage to charge my car off that 100 amp main breaker. If you're talking about a typical apartment with a 12000 BTU AC and a small electric stove, you're looking a peak load of 25-30 amps and average load of 10 amps or less. In all but the most unusual circumstances, charging an EV is not going to be a problem. Putting the wiring in would be more of problem than the load calcs. The Fudge factor you allude to is just that. A guess as to what typical loading is. .4 is just a rule of thumb meant to get you into the ballpark. To be really accurate, use an ammeter to measure actual loading.
 
johnlocke said:
My point still stands. Even with my large house and numerous loads I still manage to charge my car off that 100 amp main breaker. If you're talking about a typical apartment with a 12000 BTU AC and a small electric stove, you're looking a peak load of 25-30 amps and average load of 10 amps or less. In all but the most unusual circumstances, charging an EV is not going to be a problem. Putting the wiring in would be more of problem than the load calcs. The Fudge factor you allude to is just that. A guess as to what typical loading is. .4 is just a rule of thumb meant to get you into the ballpark. To be really accurate, use an ammeter to measure actual loading.
Your point is that you probably violate NEC if all your loads were on one main breaker and you did not use NG. And so far as I know, NEC requires an estimate.
 
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