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So far, EVs have been limited to small to mid-size cars that get 3-5 miles per kWh. Those easily recharge overnight at 8, 16, 24, 32, 40, or 48 Amps AC converted by the car to DC. Those amounts of power are generally fairly readily available with minor to moderate modifications of a typical home's electric service.

The next generation of EVs will include much bigger vehicles some of which will routinely tow trailers - boats, horses, campers, utility trailers, etc.

In the next 3-5 years EVs with 150 - 200 kWh batteries will become commonplace - think Cybertruck, Rivian, Ford Transit van EV, GM Sierra Pickup, GM Hummer SUV and many more to come...look at the mix of vehicles around you as you drive and ask yourself how they convert to EVs.

Suppose a 2 mile / kWh vehicle driven 150 - 200 miles / day needs to recharge in 8 hours at home. That's 9 - 12 kW or more...what if two or more EVs need charging?

Do homes evolve to have 300-400 Amp service to cover either multiple AC EVSEs or 15 - 25 kW DCFC? What does that look like in terms of retrofitting existing neighborhoods? Utility transformers are sized way below individual home service capacities since actual continuous loads are far less (~10%) than panel main breaker current rating. That works since typical home loads are very intermittent - drying clothes, cooking, heating water and HVAC operation are typically short term - less than an hour at a time. EV charging is a bit different in that the load may persist for hours at a time.

In the near term, electric utilities benefit as their installed infrastructure enjoys increased capacity factors and revenue without additional investment. My heavy Uber driving increases our electricity bill $100 - $150 per month which the utility enjoys without having had to upgrade my service.

Does a hybrid scenario evolve wherein heavy EVs get some (50 - 100 miles) charging at home but may sometimes have to visit a very fast DCFC station to gain at least 200 miles of range in no more than 10 minutes...at 2 mi / KWh? 200 miles of range gain in 10 minutes requires a charge rate of 600 kW or 750 Amps at 800 Volts. That's a lot of power, but mainstream America isn't likely to accept EVs unless and until the ownership experience resembles ICE.

Much of the attention on growth of EVs is on public fast charging infrastructure, but the pattern of ~90% of EV charging being at home or parked at work is likely to continue - the ramifications of that will be interesting.
 

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Don't have the time at the moment to fully explain it but with more EV penetration it will change the utility landscape. Think AC units, everyone has one but they don't run all the time but cycle on and stay on longer as it gets hotter. For example if an AC unit pulls 25 amps but only runs 25% of the time then on average 4 houses would have one AC unit running all the time. Well if you change that to it runs 50% of the time then the total neighborhood load has just doubled. EV are a bit different as they charge at a continuous current say 32 amps for a level 2 charger. If you have 10 houses with an EV then the total load will be 320 amps. Without the cycling on and off the load quickly becomes large. I see some ability of the car to schedule charging but IMO in the future we will need to have the ability to allow the utility to schedule charging so that the total system load is optimized. A step further would be the ability for an EV to be able to put power onto the grid from it's batteries.
Utility bills are interesting things particularly for regulated utilities. A component of the bill is for the installed infrastructure and a portion is for the generation costs.

In the near term i think house wiring will not change radically but newer houses will be built with charging infrastructure built in. It is easy to think that everyone will be charging overnight at 32 amps for the whole night but the reality people will charge to replace what was used during the day and most people do not drive that far. Their charging can be at higher current for shorter times or a lower current for longer times. I see this issue as begging and ripe for a good charging scheduler so that the total impact to the grid is minimized.
 

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Utilities and consumers stand to benefit from EVs, especially when combined with partial utility controlled charging. The customer has an app where they specify at what time the vehicle must be charged and ready to go, and the utility decides when to charge the vehicle to meet that requirement, usually at night when demand is low. It brings baseload up, so that the difference between peak and baseload is reduced. Bringing baseload closer to peak increases efficiency and reduces overall cost of generation.

As pointed out above, that's the first and easiest thing to implement. Next would be full V2G where EVs are capable of supplying electricity during peak demand. Owners would be able to opt in to supply a specified portion of their battery capacity to feed the grid when the cost of electricity soars. They would be credited their contribution during these high-cost periods of demand.

I don't know how the electrical codes are written, but my 200A service could easily feed 2x 40 amp loads at night. You bring up a good point that those regularly needing 150+ kWh or more will struggle to replenish in a typical evening of charging, but that would be atypical for most.

One more thing about 200 amp service; that was made standard during a period of time where incandescent lighting and less efficient appliances were the norm. With LED lighting and much more efficient appliances, I have less need of such service. EVs are the perfect thing to utilize the service I already have.

The few that need more service can probably afford to install a higher level of service. EVs at home will be a net benefit to the grid. It's DCFC that will wreak havoc on infrastructure during Thanksgiving travel. Utilities will need to build up infrastructure to accommodate a few hours per year where demand is extremely high.
 

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Some good points already mentioned. The current generating capacity may be far under the capacity needed if all of us charged at the same time, during evening peak demand periods. But, with enough owners shifting scheduled charging to later in the evening, we probably have more than enough for a fleet of 50-60% of cars being EV.

Utilities will likely shift peak demand times as loads shift. We already see solar generation causing some shifts in So Cal where peak solar generation in afternoons while AC use tends to be high is offsetting the grid demand, thus shifting the peak times to later in the afternoon. If large numbers of EV owners hold off to 10PM then suddenly start demanding power, peak times may shift to later in the night.

At some point, utility demand-response will be necessary as @redpoint5 suggests. V2H and V2G solutions could also help level demands.

There are many variables, but utilities tend to think in a macro sense about supply and demand. Sure, there will be large capacity and higher loads with some EVs, but many will be less impactful due to a portion being smaller cars and less mileage to recover. The utilities need to understand what causes the shifts, and adjust their generating schedules accordingly.

Certainly, some older homes may require upgrades, and some neighborhoods may require higher output transformers. At the same time, growing rooftop solar and local storage may offset or delay the need for upgrades.

Residential rates are based on relatively low short term demands, typically under 50kWh/day. But higher demands for large EV with high mileage uses may drive a push by utilities to impose a demand-charge on higher use customers who would tend to push systems for upgrades in their areas. Demand charges for commercial customers addresses the high load users.

All of this is not really new to utilities, but their attention to higher load factors has primarily been with commercial customers. Residential use trends may force them to consider a closer look at that segment of their customer base.
 

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Utilities are typically some of the biggest promoters of EVs. They have a vested interest in making sure that the grid is used more efficiently than it currently is, hence the growth in TOU plans. EVs fit ideally into their plans when most EV owners plug in for a few hours at night.

Some EV opponents cite the fact that some people, especially in cities, live in apartments and don't have access to night time charging. They obviously never lived in an apartment as apartments are typically in the denser and more transit accessible parts of a city. The current trends are to push more people who live in those denser neighbourhoods to ditch their second cars and commute by transit or bike. Even when apartment dwellers still commute by EVs, their commutes are shorter than suburban households in single family homes and thus require less electricity that could be achieved through L1 AC charging at work or at their apartment. Also parking is a bigger consideration in denser areas with a greater number of cars being more efficient small cars like the Bolt instead of less efficient ones like the Hummer EV.

Multi-family resident concerns aside, most North Americans live in a detached house that could very easily accommodate a 40 A receptacle in their driveway or garage. In those cases, most if not all of the charging will be for a few hours during periods of least demand. Utilities could intelligently ("Smart") control chargers to make sure that there is an even distribution of demand at night. Even with energy hogs like the Hummer EV or Audi E-Tron, most daily commutes can be covered within a fewer hours at 240 V @ 32 A, similar to the load required by home and commercial AC units during the day.

DCFCs are where things get tricky. While currently a few automakers and non-utility companies are in the DCFC game, we will begin to see more utility and convenience store companies take the DCFC development spotlight. For utilities, in order to get those night time customers, they need to make complete EV ownership possible with near seamless transition from ICE (for the typical driver) when it comes to long distance travelling. With convenience store franchises, they can use DCFCs and partnerships with franchise restaurant as a way to lure customers into spending more (time and money) at their establishments. For utilities and convenience store companies, DCFCs could lose money, yet still be considered valuable because the DCFC isn't their source of profits (for convenience stores fuel sales are low margin). Network operators like Chargepoint will be forced to enter a more niche DCFC ownership model and will more likely end up being the network operators (not owners) of DCFCs and private L2 stations. As far as future power draw from DCFCs, at the moment they are negligible and can very easily be forecasted into future peak daytime demand, especially when even greater usage demand statistics become available.

In many provinces and territories in Canada, the local power utility corporation is the largest owner of DCFCs and operate them at a loss and use Flo (similar to Chargepoint) to provide the network. Most of these power utility corporations only plan to break even or make small profit from DCFCs in the future. Meanwhile, Circle K/Couche Tard has big plans to copy their Norwegian success into North America.
 

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I had some solar panels at my last House and seriously considering adding a 10-15kW system to our current home WHILE SOLAR IS CHEAP. As the Demand for electricity grows , the prices increase not only for your local utility but also solar as everyone starts looking at alternatives.
 

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Perhaps garages in new homes will be built with their own service line and breaker box that are specifically meant for EV charging, separate from the home circuit. Would be relatively easy to retrofit most existing homes to do this as well. Not sure how much of an extra hassle it would be for the utility company or homeowner to have separate service lines.

I'm thinking about looking into adding a new, separate service line into my garage in the future as my wife is leaning toward getting the Mach-E in a few years. Her commute is 120 miles round trip, so she'd have to charge almost every day. My home panel is already maxed out and on the opposite side of the house from the garage (current 240 V line is run through a finished basement to the garage). Might not be that much more money & hassle to have a new service line put in (we have underground power utility lines) compared to upgrading the home panel & service, and running another line for a sub-panel in the garage.
 

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Perhaps garages in new homes will be built with their own service line and breaker box that are specifically meant for EV charging, separate from the home circuit. Would be relatively easy to retrofit most existing homes to do this as well. Not sure how much of an extra hassle it would be for the utility company or homeowner to have separate service lines.It wouldn't be difficult,
Not too difficult if the existing service line is capable of heavier loads, just split the incoming to two meters and terminate each meter on separate panels. SDG&E has a TOU plan for EVs which allows the customer to install a separate meter for EV charging. Apparently the meter is at customer cost, presumably $100-200.

If a second line, or upgraded line is required, it could get more costly.
 

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I had some solar panels at my last House and seriously considering adding a 10-15kW system to our current home WHILE SOLAR IS CHEAP. As the Demand for electricity grows , the prices increase not only for your local utility but also solar as everyone starts looking at alternatives.
Solar is tech, prices will continue to drop.

 

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Utilities and consumers stand to benefit from EVs, especially when combined with partial utility controlled charging. The customer has an app where they specify at what time the vehicle must be charged and ready to go, and the utility decides when to charge the vehicle to meet that requirement, usually at night when demand is low. It brings baseload up, so that the difference between peak and baseload is reduced. Bringing baseload closer to peak increases efficiency and reduces overall cost of generation.

As pointed out above, that's the first and easiest thing to implement. Next would be full V2G where EVs are capable of supplying electricity during peak demand. Owners would be able to opt in to supply a specified portion of their battery capacity to feed the grid when the cost of electricity soars. They would be credited their contribution during these high-cost periods of demand.

I don't know how the electrical codes are written, but my 200A service could easily feed 2x 40 amp loads at night. You bring up a good point that those regularly needing 150+ kWh or more will struggle to replenish in a typical evening of charging, but that would be atypical for most.

One more thing about 200 amp service; that was made standard during a period of time where incandescent lighting and less efficient appliances were the norm. With LED lighting and much more efficient appliances, I have less need of such service. EVs are the perfect thing to utilize the service I already have.

The few that need more service can probably afford to install a higher level of service. EVs at home will be a net benefit to the grid. It's DCFC that will wreak havoc on infrastructure during Thanksgiving travel. Utilities will need to build up infrastructure to accommodate a few hours per year where demand is extremely high.
Daytime, your roof top solar sends power to the grid while you are plugged in across town at work, charging. Utility rightfully charge a commission for enabling you to effectively "use" your rooftop solar from across town.
Night time, while your home power consumption is higher, you are not charging your EV.
Definitely upgrades required at commercial zones, no upgrade should be required at residential zones as long as the average home is 5-10KW solar. Since commercial zones are denser, it's cheaper.
 

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One thing to point out, more people that purchase EVs will likely install solar at their homes (if they own a home). I purchased a 2020 Bolt a few months ago and plan to install solar panels in back of my house.
 

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Not too difficult if the existing service line is capable of heavier loads, just split the incoming to two meters and terminate each meter on separate panels. SDG&E has a TOU plan for EVs which allows the customer to install a separate meter for EV charging. Apparently the meter is at customer cost, presumably $100-200.
FWIW, our local utility has a base service charge of $20 month just to have the meter and have it read and billed. Any consumption is tiered charge.

jack vines
 

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When thinking about grid-scale, you have to think in averages. The average driver drives 40 miles per day. The least efficient vehicle will get maybe 2 miles/kWh. In the winter, that could be halved, so 1 mile/kWh. But on average, I would guess that it would be about 2 miles/kWh. So 20kWh / day. Even a 32A / 240V EVSE would only take about 3 hours to provide 20kWh. Sure there will be hot spots (say a wealthy neighborhood with lots of large vehicles and towable toys). But on average, this is actually not as much of a challenge as you might think.

As it is, I am already servicing my two EVs from a single 32A EVSE. We simply alternate which car we charge at night. Either one will be fully charged by morning.
 

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Daytime, your roof top solar sends power to the grid while you are plugged in across town at work, charging. Utility rightfully charge a commission for enabling you to effectively "use" your rooftop solar from across town.
Night time, while your home power consumption is higher, you are not charging your EV.
Definitely upgrades required at commercial zones, no upgrade should be required at residential zones as long as the average home is 5-10KW solar. Since commercial zones are denser, it's cheaper.
One thing to point out, more people that purchase EVs will likely install solar at their homes (if they own a home). I purchased a 2020 Bolt a few months ago and plan to install solar panels in back of my house.
What has solar to do with the price of tea in China?

Solar can only make it more costly to operate the grid because it introduces supply sporadically, and other generation capacity needs to be available to supply 100% of demand for those times when solar generates nothing. "Batteries, batteries!" solar believers say. If you haven't noticed, battery supply is the constraining component to making EVs in the first place. Tesla isn't making the electric semi precisely because they don't have the battery supply to do it... then there's the cost.

PV is easy to accommodate when hardly anyone has it, but each additional amount increases the cost of electricity for everyone. Even in the Oregon valley where the sun shines only half the year, and at a low angle, many large areas have reached the limit for PV that our utility can handle. My parents and I just barely got our jobs accepted before the utility closed our zones for further PV.

It's not economically feasible to have homes average 5-10 kW of solar. We're averaging mere watts per household and already seeing restrictions.

The color areas are now restricted for PGE customers
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That's not to say that solar has no place now or in the future, but it's role now is small, and it's not THE solution in the future. Electricity generation will always be eclectic until we have a breakthrough with fusion.
 

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What has solar to do with the price of tea in China?

Solar can only make it more costly to operate the grid because it introduces supply sporadically, and other generation capacity needs to be available to supply 100% of demand for those times when solar generates nothing. "Batteries, batteries!" solar believers say. If you haven't noticed, battery supply is the constraining component to making EVs in the first place. Tesla isn't making the electric semi precisely because they don't have the battery supply to do it... then there's the cost.

PV is easy to accommodate when hardly anyone has it, but each additional amount increases the cost of electricity for everyone. Even in the Oregon valley where the sun shines only half the year, and at a low angle, many large areas have reached the limit for PV that our utility can handle. My parents and I just barely got our jobs accepted before the utility closed our zones for further PV.

It's not economically feasible to have homes average 5-10 kW of solar. We're averaging mere watts per household and already seeing restrictions.

The color areas are now restricted for PGE customers
View attachment 34295

That's not to say that solar has no place now or in the future, but it's role now is small, and it's not THE solution in the future. Electricity generation will always be eclectic until we have a breakthrough with fusion.
... Renewables are so sporadic and unreliable in California... sometimes when the sun it out, you'd get zero KW out of it. So weird! Here, have some more blue pill. LOL

34297


34298
 

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... Renewables are so sporadic and unreliable in California... sometimes when the sun it out, you'd get zero KW out of it. So weird! Here, have some more blue pill. LOL
That's an example of a day. Consumers don't expect power 95% of the days, but 100% of them.

Here's what solar production looks like in an ice storm
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...and when fires blot out the sun for weeks
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...and a typical Oregon day
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So far, EVs have been limited to small to mid-size cars that get 3-5 miles per kWh. Those easily recharge overnight at 8, 16, 24, 32, 40, or 48 Amps AC converted by the car to DC. Those amounts of power are generally fairly readily available with minor to moderate modifications of a typical home's electric service.

The next generation of EVs will include much bigger vehicles some of which will routinely tow trailers - boats, horses, campers, utility trailers, etc.

In the next 3-5 years EVs with 150 - 200 kWh batteries will become commonplace
I doubt this will actually happen. If it does, we will have accomplished nothing, but distraction. Reducing the size of private vehicles, and the size of the private fleet, is vital to reducing CO2 emissions.

@redpoint5, now this guy is a real optimist.

 

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That's an example of a day. Consumers don't expect power 95% of the days, but 100% of them.
5-10KW is probably what a family with 2 EVs would need.

So the example I mentioned was to charge EV during the day and V2G at night to run the house. Not a today thing but a let's work towards that goal.

BTW, for night time, check out Texas and the Midwest with their wind farms. For that matter, so is the America NW. You are part of the western grid. No one says you are limited to locally generated power (like Texas big mistake).

Time for you to take another blue pill. LOL
 

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So the example I mentioned was to charge EV during the day and V2G at night to run the house. Not a today thing but a let's work towards that goal.
I'm all for V2G and V2H schemes as these actually help to levelize grid demand. Solar by itself does the opposite. Only solar by itself is cost-competitive, and only so long as it doesn't exceed a certain low percentage of electrical generation. How do I know? Because that's exactly what utilities are doing. If solar was cheaper, they would invite me to pay a lower bill for opting in for solar generation. They do the opposite.

There is a likely a place in the future for solar to be competitive with other generation sources, but in certain locations only. Saying solar is the solution is like saying geothermal is the solution. True, that's the solution if you happen to live in Iceland or can get a permit to tap into Old Faithful. Every geographically unique area lends itself to differing electricity generation portfolios.

Time for you to take another blue pill. LOL
You keep saying that, but you'll be relieved to know everything is functioning normally downstairs. ;)
 

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Saying solar is the solution is like saying geothermal is the solution. True, that's the solution if you happen to live in Iceland or can get a permit to tap into Old Faithful.
Here's a test you can do to tell if a location can be used for geothermal energy. Grab a fistful of dirt from the ground and taste it. If it tastes like dirt, you can use the location for geothermal energy. But some areas do have higher temperature increases per depth, making it cheaper/easier. Most of Nevada is about as good as Iceland.
 
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