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Charging cars at home at night is not the way to go: study

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Re: Charging cars at home at night is not the way to go: study

#91

Post by wing-_-nuts »

ctrlmeta wrote: post #28
wing-_-nuts wrote: post #8

Earlier quoted context omitted.

Frankly, if a user cannot trust their EV to charge without going up in flames it is not ready for prime time and should be recalled. Period.

Yes! It surprises me that the reliability issues in charging an EV are not discussed more. This bears more discussion and subject to regulations. It is not ok for companies to push EVs to general consumers without creating a good safety record.

I think we already have enough regulations to hold companies liable for creating a dangerous product, we simply need to use them to hold corporations accountable.

None of this 'oh, our owners manual says you should only charge in these special conditions or we can't be held responsible'. Nope. You make a product and it hurts people or destroys property? You better make your peace with punitive damages that'll make you wish you properly tested before shipping to customers.

Re: Charging cars at home at night is not the way to go: study

#92

Post by elzbardico »

calrain wrote: post #32

My understanding was that it helps countries with nuclear powered base electrical load to use that power at night, when there isn't a lot of demand. With further development, a key side benefit is that the grid can then tap into about 5% of your cars battery storage during the day when demand is higher (if you allow it).

The same issue applies to almost every country's baseload generation infrastructure, with a small exception of hydro (that has some small degree of dispatchability), it is not exclusive to nuclear power generation. Traditional thermo-electric plants also can't ramp up and down their power levels instantaneously.

Re: Charging cars at home at night is not the way to go: study

#93

Post by jayd16 »

lbriner wrote: post #43
denimnerd42 wrote: post #18

I would be curious about a study done for the Texas market. From what I understand, you'd definitely want to charge at night due to the vast amounts of wind power available and the otherwise low demand. Even better would be to plug the car in at all times when parked either at work or home and it just charges when the rate is cheapest. You don't need to charge every day to refill that 20 or 30 miles.

I guess the issue with this report is that it is specific to the unique mix of energy that the (west of the) USA has compared to other areas/countries. Countries with a lot of nuclear see that energy wasted at night because you can't just dial down the level very quickly, in that sense, in most of Nothern Europe this would be desirable. In countries that have extreme levels of solar, clearly this only works during th…

Smart metering would make it easily enforceable but couldn't tie into the smart thermostat system to at least delay charging to off peak hours?

Re: Charging cars at home at night is not the way to go: study

#94

Post by shiftpgdn »

landemva wrote: post #86
GoOnThenDoTell wrote: post #55

Earlier quoted context omitted.

time-of-use is also cognitive load that can cause anxiety

For the small amount I consume, tiny potential savings are not worth the mental hassles. I switched a residence to flat rate to avoid these mental games.

My house uses around 3-4MW/mo. I hyper optimized when I had true spot pricing before Griddy energy was disbanded by the state. My bill was extremely low compared to what I pay now.

Re: Charging cars at home at night is not the way to go: study

#95

Post by elzbardico »

m0RRSIYB0Zq8MgL wrote: post #20

> Current time-of-use rates encourage consumers to switch electricity use to nighttime whenever possible, like running the dishwasher and charging EVs. This rate structure reflects the time before significant solar and wind power supplies when demand threatened to exceed supply during the day, especially late afternoons in the summer. So, if you have a grid that doesn't heavily rely on solar then charging at night ma…

Late morning and early afternoon. So, basically, people would charge their cars where they park them during the day while they work, not at home while they sleep.

Seems very doable to me.

Re: Charging cars at home at night is not the way to go: study

#96

Post by Gasp0de »

DropPanda wrote: post #60
Gasp0de wrote: post #46

Earlier quoted context omitted.

Inductive charging seems like a horrible solution as it must surely be extremely inefficient? Also, if dynamic charging refers to charging while in motion, why would that be a good solution? It seems way more complicated and inefficient than charging while stationary, and personally owned cars are stationary more than 90% of the time.

Surprisingly, transmission efficiency (grid to motor) does not appear to be lower with inductive methods than conductive. Numbers above 90% should be expected. A bit lower for the dynamic (in-motion) solutions, but not so much that it’s a deal breaker. There seem to be much larger savings/costs elsewhere in the system that make transmission efficiency of less importance. Cars that are stationary most of the time are…

This source (https://batteryuniversity.com/article/bu-412-charging-withou....) says efficiency is only 75-80% when charging inductively. Do you have any better sources for those 90%?

Re: Charging cars at home at night is not the way to go: study

#97

Post by NickM »

Schroedingersat wrote: post #85
NickM wrote: post #78

Earlier quoted context omitted.

If you're regularly committing a certain percentage of your car's battery capacity to powering your house, wouldn't it make more sense to just have a stationary battery at home? Otherwise you can't rely on that extra range in your car if you need it to power your home anyway, and you're just spending extra energy carrying around extra battery weight in your car every day.

I wonder if there's any correlation between times someone travels 400 miles and times when they are not home... we probably need a study or something to figure it out.

The problem is, you need a full charge in the morning if you're leaving on a road trip, so then your car will not be powering your house the night before. This would likely lead to big spikes in demand the night before the start of holiday a weekend, for example.

Re: Charging cars at home at night is not the way to go: study

#98

Post by elzbardico »

upsidesinclude wrote: post #80
m0RRSIYB0Zq8MgL wrote: post #20

> Current time-of-use rates encourage consumers to switch electricity use to nighttime whenever possible, like running the dishwasher and charging EVs. This rate structure reflects the time before significant solar and wind power supplies when demand threatened to exceed supply during the day, especially late afternoons in the summer. So, if you have a grid that doesn't heavily rely on solar then charging at night ma…

I appreciate that you acknowledge Californians show up late and leave early

Only in Sacramento

Re: Charging cars at home at night is not the way to go: study

#99

Post by notatoad »

GoOnThenDoTell wrote: post #55
Grimburger wrote: post #39

Earlier quoted context omitted.

> The solution is simple. Make electricity cheaper when it's more available From the parts of the world I come from the majority of people are vehemently opposed to time of use pricing. Because that's when they use it most. They and their political representatives would much prefer to keep taking from those who consume in off-peak rather than fix the underlying mechanism.

time-of-use is also cognitive load that can cause anxiety

it is, but that's the part that technology can actually help us with. all the internet-connected smart home stuff that companies have been trying to sell us is a bit silly when electricity is sold at a flat rate, but if my car charger, my clothes dryer, or my or my dishwasher could sit idle until electricity prices drop into the cheap zone and then turn themselves on, that internet connection becomes useful.

an attitude of "i don't want to deal with the stress of thinking about the electricity i use" is absolutely the sort of luxury that you should pay extra for, the people willing to schedule their power usage to reduce peak demand should be paying less than the people who aren't willing to do that.

Re: Charging cars at home at night is not the way to go: study

#100

Post by khuey »

shiftpgdn wrote: post #94
landemva wrote: post #86

Earlier quoted context omitted.

For the small amount I consume, tiny potential savings are not worth the mental hassles. I switched a residence to flat rate to avoid these mental games.

My house uses around 3-4MW/mo. I hyper optimized when I had true spot pricing before Griddy energy was disbanded by the state. My bill was extremely low compared to what I pay now.

Average US residential consumption is under 1MWh/mo so you are definitely not a typical customer.
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