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Will EV's make electricity expensive? Need good answer.

Chris_V

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This statement came up on a Mach-E forum: "When everyone starts using Electric Vehicles the price of Electricity will soar!" They were complaining that the cost of DC fast charging is already expensive and that it will only get worse. Even residential rates are going to go up. Then they said solar and batteries will become more expensive too. Actually even people in my day to day life believe some narrative like this.

First I answered that we should be charging at home 90% of the time. Second I said that if residential rates go up we can just make our own energy with solar and that caps a lot of upward pressure for electricity.

Then they complained that solar was expensive investment. I said that Mach-E's cost way more than a typical solar install, and if we can afford to buy brand new Mach-E's money really isn't an object.... They didn't like that response.

Did I shoot myself in the foot or are these people just not getting it?
 
As usual, it depends. If the country is willing and able to make investments in the grid and power generation, the prices don't have to go up. The obvious example here is Norway, were 77.5% of all new cars bought are EVs. Norway generates most of its power from hydro.


If on the other hand, no investments are made in grid infrastructure, and monopolies in the market want to maintain the status quo, prices will undoubtedly go up. So in the end, it'll depend on where you are.
 
In America right now there has got be a price point where investing in solar is a no-brainer. Fortunately, my rates are capped at $.10per kwh no matter how much I use, but if it was $0.40per kwh I think I'd be covering my whole roof with panels.
 
Before making blanket statements, you have to start with the numbers. The details matter greatly here.

With my own research, I'm finding that an EV might consume about 0.4 to 0.5kWh of power per mile driven. So, guestimating that I might want to drive 30 miles from my homestead down the hill to town and buy groceries, my round-trip might consume about 30kWh of power.

Level 1 EV charging is 12A at 120VAC, which I could manage for maybe about 10 hours per day with my solar system. So, one trip into town would require two days of charging once I returned.

Level 2 EV charging varies from 20-50A at 240VAC. With my system, I could charge at 10A for about 8hours, but if forced to charge with at least 20A, then maybe 2-3 hours per day. I'd need to add a second charge controller to handle that much instantenous power for several hours.

Your statement about charging at home with solar is just not going to work. Assuming you arrive back home at ~5pm, there just is not going to be enough solar resources left at that time of day. And trying to pull 15kWh of power out of your solar batteries doesn't sound realistic.

The only way night-time charging is appropriate is when you are grid-connected, and you can start charging in the evening when rates start going down. The only way that solar would work is to have solar parking bays that you drive into at work, and immediately plug in to charge. After 8 hours at work, your batteries will be charged enough to get you back home.
 
Gotta look at it as a percentage of total consumption. Supply and demand and whatnot.

Right now EV power is a small fraction of total generation. Not a big deal.

I believe I read an estimate that by 2040 they will account for something like 1800 TWh annually, globally, and even that will only be about 5% of production.

I don't think it'll have a terribly dramatic effect.
 
60m

First I answered that we should be charging at home 90% of the time. Second I said that if residential rates go up we can just make our own energy with solar and that caps a lot of upward pressure for electricity.

Then they complained that solar was expensive investment. I said that Mach-E's cost way more than a typical solar install, and if we can afford to buy brand new Mach-E's money really isn't an object.... They didn't like that response.

Did I shoot myself in the foot or are these people just not getting it?
I think you missed your foot. Most daily drivers are under 50miles/30kWh each day. So a 120v 20A circuit can get most cars charged overnight. Solar would just require you to push power onto the grid during day and pulling it off at night. Not such a terrible thing. For off-grid could use batteries. I don't think grid will be terribly taxed in most places. People driving EVs are probably investing in solar panels as well (while whining about the cost).. City grids may be taxed the hardest. Many cars to charge without room for solar panels. I would expect the price of electricity in urban areas to have fees attached for higher usage. If in fact the price of electricity goes up those3 of us with panels may see an actual return on our investment.
 
Sorry if you think I'm attacking you. But, I very much have to drive far more than 50 miles per day. You need to start with the numbers, not rosy predictions. 90% of the problems I see on this site is people never doing the math first before they start building something.

You are not going to get a 20A/120V charger. They might not even be made. They make it a 12A standard for a reason, and that is so the standard EV user can simply plug directly into a wall socket. It's for simplicity, not performance. Your typical household socket will not handle 20A, so they do not make them that way. Maybe you only drive less than 50 miles per day, but in California a lot of regular folks have double that every day. 1.4kWh out of the wall might not get you there.

Getting a 20A+ 240V charging circuit installed in your house is also doable, but not going to be cheap. On solar, it's going to be very hard. I'd guess that my solar system is likely to be larger than about 95% of the other posters here, and I would be very hard-pressed to run a 240V charger for very long.
 
Sorry if you think I'm attacking you. But, I very much have to drive far more than 50 miles per day. You need to start with the numbers, not rosy predictions. 90% of the problems I see on this site is people never doing the math first before they start building something.

You are not going to get a 20A/120V charger. They might not even be made. They make it a 12A standard for a reason, and that is so the standard EV user can simply plug directly into a wall socket. It's for simplicity, not performance. Your typical household socket will not handle 20A, so they do not make them that way. Maybe you only drive less than 50 miles per day, but in California a lot of regular folks have double that every day. 1.4kWh out of the wall might not get you there.

Getting a 20A+ 240V charging circuit installed in your house is also doable, but not going to be cheap. On solar, it's going to be very hard. I'd guess that my solar system is likely to be larger than about 95% of the other posters here, and I would be very hard-pressed to run a 240V charger for very long.
The average commute to work is about 26minutes each way. I suppose that is near 50 miles/day The average mileage put on a car is near 14000. Assume 12000 is used for back and forth commute then that is near 250 miles/week or 50mi/day. I am talking average, not what any one person might do. So far my math seems to be holding up.

I said a 20A circuit, and didn't mention charger size. A 20A/120v charger is not a design oddity and is actually simple. Most circuits in the home are fused for 20A. That is why I chose that number. A well designed charger with power factor correction could pull 2kW out of a 20A line. User could program current if on a 15A breaker. Rackmount 3200W chargers with PFC are less than $600. These units are de-rated to 70% on 120v lines. TRC electronics.

Using 0.5kWh/mile results in 25kWh which is then 12.5 hours of charge time at 2kW. Easily doable. If your commute is double that then a 4 or 5 kW charger might be a better way to go. A line to the garage to run a charger might not be any more expensive than a line to the electric range or cloths dryer. I would expect that anyone who is going to make the investment in an EV might not balk at a few hundred bucks for a line out to the garage. I expect most be driving EV soon and most garages will have charging ports. We know that we need 25kWh for the average charge. That would be a 6kW array here in New England. I suppose you would need a larger array for your 30kWh trip into town. Again, the city dwellers will have to pay utility rates as I don't expect cities to be plastered with solar arrays anytime soon.

I was on the design team for a very large inductive coupled 50kHz resonant charger when I was at UW Madison. This was for EVs - before there were EVs, That was in 1995.

I don't think you are attacking me and enjoy the dialog so thank you for that. I work with numbers and have been over this a few times. I don't think I have made any rosy predictions and stand by what I presented. If you disagree with anything I said then please point it out. I agree-I see a bit of suspect data on this site. It would be a full time job just correcting it. I don't have time for that so just let it go. I do disagree with your blanket statement that charging from home with solar just isn't going to work. It works on both 120v and 240v commercial lines. I have enough surplus solar to get back and forth to work 30mi each way - 3 days/week. So for me solar would work with my system as is. My excess is just for cloudy winter days,. If you have the space for a larger array then someday you may find the electric rates high enough to justify a larger array for your trips into town.

And thank you OP Chris_V. I don't think we can predict what the price of electricity will do in the future based on impact of EV on grid. My money would bet that prices will go up as ECON101 supply and demand will apply. Again, congested cities will see the worse of it. Grid will have to be reinforced in some manner and that will cost money. Those in charge are on the greedy side so maybe that will have effect as well.
 
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Getting a 20A+ 240V charging circuit installed in your house is also doable, but not going to be cheap.

Everything is expensive when it is a unique, one-off installation. If there is a market for 1 million such chargers, they will be cheap enough. For us DIY types, wiring it will cost about $200 (permit will cost more, and take more hours, than doing the work). Add to that whatever the charger itself costs ($400?)


A 20A+ 240V is just an electric dryer circuit. Or the circuit for a 5kW grid-tie inverter. And a 5kW grid-tie inverter system complete with panels isn't expensive, it is considerably cheaper than the power it produces.

The U.S. has passed 2 million PV systems.

 
The EV will pay for the additional electricity needed from the grid.
The cost to charge at home can be half compared to gasoline.
 
Everything is expensive when it is a unique, one-off installation. If there is a market for 1 million such chargers, they will be cheap enough. For us DIY types, wiring it will cost about $200 (permit will cost more, and take more hours, than doing the work). Add to that whatever the charger itself costs ($400?)


A 20A+ 240V is just an electric dryer circuit. Or the circuit for a 5kW grid-tie inverter. And a 5kW grid-tie inverter system complete with panels isn't expensive, it is considerably cheaper than the power it produces.

The U.S. has passed 2 million PV systems.

The Tesla charger at $415/9.6kW is a bargain.
 
Sorry if you think I'm attacking you. But, I very much have to drive far more than 50 miles per day. You need to start with the numbers, not rosy predictions. 90% of the problems I see on this site is people never doing the math first before they start building something.

You are not going to get a 20A/120V charger. They might not even be made. They make it a 12A standard for a reason, and that is so the standard EV user can simply plug directly into a wall socket. It's for simplicity, not performance. Your typical household socket will not handle 20A, so they do not make them that way. Maybe you only drive less than 50 miles per day, but in California a lot of regular folks have double that every day. 1.4kWh out of the wall might not get you there.

Getting a 20A+ 240V charging circuit installed in your house is also doable, but not going to be cheap. On solar, it's going to be very hard. I'd guess that my solar system is likely to be larger than about 95% of the other posters here, and I would be very hard-pressed to run a 240V charger for very long.
That entire post is negated by the fact that averages account for everyone and work just fine when discussing something that's a global scale.

That's not a rosy prediction but a statistical fact.

The average American drives less than 30 miles per day. Factually.

And we drive more per day than any other country apparently, so you can safely assume that the whole rest of the world averages 30 or less.

Just because your individual needs are higher doesn't mean the assessment is false.

It just means you have above average usage. Where you drive 50 miles a day I probably average less than 10 and that's including the few times a year where I'll drive a thousand miles on a weekend. I live 1.5 miles from work, my bank, and the grocery store I shop at. All virtually on the same corner lol
 
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The average American drives less than 30 miles per day. Factually.

Where I live (rural) most people drive well over 50 miles a day. And in an urban area I am sure many may drive less. That 30 miles average for everyone may be correct, but IMO I don't think it is correct for the "average" person. And even where it may be 30 miles or less, how much is while sitting stuck in traffic. The EV may not be moving, but it will still be running AC, heater, lights, etc.
 
Where I live (rural) most people drive well over 50 miles a day. And in an urban area I am sure many may drive less. That 30 miles average for everyone may be correct, but IMO I don't think it is correct for the "average" person. And even where it may be 30 miles or less, how much is while sitting stuck in traffic. The EV may not be moving, but it will still be running AC, heater, lights, etc.
That makes no sense. If the average driver is 30 miles then the average driver is 30 miles.

The point of the thread is the total increased cost of power by increased demand to the planet (or even one country) and the average is the figure you use.

Realistically you're correct about the power consumption though. There are average figures for that available too which anyone taking this seriously would use instead.


You're also possibly confusing average with median, which is more appropriate when dealing with a sample of a population and trying to identify which market segment to chase after to sell equipment to. If most drivers drive 50 miles a day then the median will be higher than the average and you'll be better off trying to sell systems to the 50 mile crowd. But that's not the topic here lol
 
That makes no sense. If the average driver is 30 miles then the average driver is 30 miles.

If you have 10 people and 9 are old and retired and only drive 5 miles a day and one is working and drives 60 miles to work that is an average of about 10 miles driven. But does that mean all drivers are average drivers? Point is you can't just take an average of of all miles driven to calculate how the cost would be spread or how to build a EV infrastructure.
 
If you have 10 people and 9 are old and retired and only drive 5 miles a day and one is working and drives 60 miles to work that is an average of about 10 miles driven. But does that mean all drivers are average drivers? Point is you can't just take an average of of all miles driven to calculate how the cost would be spread or how to build a EV infrastructure.
Again you're confusing average and median.
 
The power company doesn't care which people contribute the most to the demand. All they care about is the demand... well. Within a very specific context of course.

And when factoring in an entire population, the average figure will suffice.

Of course you need to break it down to sub stations and whatever but we are not talking about actually delivering the power, only the overall effect on price through increased demand.

And the increase in demand for EV power is mouse farts compared to everything else.
 
I'm not the one who used the term average to begin with. And the point was that you can;t use that average as the basis for this thread topic.
You absolutely can.

You're right that the mileage isn't the thing to use but the average power consumption per EV per unit of time x the number of EVs is exactly the figure to use.
 
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