> It assumes people drive to the work in the morning have charging stations at work
That's a pretty reasonable assumption once electric cars are the majority of cars.
> and don't commute very far.
There are popular electric cars with a range on the order of 300 miles. The average commute is 41 miles round trip.
> Also, there's loads of people doing errands during the day, or utility vehicles transporting cargo.
The average person does not drive 300 miles a day in total, and so does not need to charge more than once a day in total. Utility vehicles will have larger batteries and more range, and will strongly prefer to charge during daylight because charging from solar will cost less.
> And lastly, few grid operators are going to accept that their grid storage may drive away on masse during the holidays.
It's storing the energy that the vehicle itself will use. If the vehicle leaves the area then so does its demand for electricity.
> During a cloudy week, you're going to have a shortfall all the time. Solar drops to 10-25% effectiveness with cloud cover
If your grid has 40GW of nuclear and 60GW average of solar (which generates 120GW during daylight) then the 120GW drops to 30GW and you have 70GW of generation, which could be less than the demand before noon. You can also run the peaker plants even though you already had a surplus in those hours so you can put even more into the batteries to have enough later in the day.
> But again, peak demand isn't at midnight it's at 8pm. You can't just hand-wave away the challenge of meeting peak demand when intermittent sources aren't producing.
Suppose you have enough nuclear to meet the demand at midnight, which is enough to meet half of the demand at 8PM. So now you need to satisfy the other half from batteries for four hours, because before 6PM the sun is still up and after 10PM the demand falls off to what you're getting from nuclear. So you don't need enough batteries to satisfy all of the demand for the 12 hours when there is no sunlight, you only need enough to satisfy half of the demand for those four hours.
> And it aligns even worse during the Winter: solar is producing the least amount of energy, cloud cover is at its greatest extent.
But there is more wind in the winter, and at night, when there is more demand for heating.
And one of the ways to decarbonize heating in cities is nuclear with cogeneration. Then you're not using electricity for heat, you're using the waste heat from the reactors, which chops off a large chunk of even the existing nighttime load.
Again, electric vehicles only work as storage if people can charge their cars at work, drive home, and then tap that storage over night.
Many vehicles aren't being used for commuting, they're used for work or running errands. They're going to be used during the day and charged at night. People aren't just going to become nocturnal in order to charge their cars. Someone who drives to work in the morning, goes shopping during the day, and picks kids up in the evening isn't going to be able to do all these chores at night.
What happens if someone's car is discharged over night right before a trip to Grandma's and now they don't have enough range? They're going to be pissed and stop letting the grid tap into their car.
> If your grid has 40GW of nuclear and 60GW average of solar (which generates 120GW during daylight) then the 120GW drops to 30GW and you have 70GW of generation
If you've got 50GW deficit over a week of cloud cover you need 4,200 GWh of storage to offset that. Consider that in many parts of the world, cloud cover can be present for a month or longer.
These are absolutely massive storage figures. The latter is about ten times the annual global battery output. And energy demand is much higher than 120 GW. US electricity demand is 500 GW. Global electricity demand is 3,300 GW.
> Suppose you have enough nuclear to meet the demand at midnight, which is enough to meet half of the demand at 8PM.
It's enough to satisfy 70% of the demand at 8PM. And since nuclear is just as cheap to run at 100% capacity all day long, it's better to scrap the bulk of your renewables because the nuclear plants make them redundant.
> But there is more wind in the winter, and at night, when there is more demand for heating.
This depends on geography. On the west coast, it's the opposite: wind produces the least energy during winter.
> Again, electric vehicles only work as storage if people can charge their cars at work, drive home, and then tap that storage over night.
They're storing the energy that they themselves use. You're not using it for your house, you're charging during sunlight and then driving home or to a restaurant after dark. It allows close to the entire demand for electric vehicles to be served from renewable generation.
> They're going to be used during the day and charged at night.
A supercharger adds 200 miles of range in 15 minutes. You go into the shop, plug into the charger in the parking lot and when you come back out in 15 minutes you don't have to charge again until tomorrow.
> What happens if someone's car is discharged over night right before a trip to Grandma's and now they don't have enough range?
They'll plug it in and charge it. Charging your car at night isn't going to be illegal, but it will cost more, so people will prefer not to, and then 95% of the charging will happen during the day.
Notice also that "overnight" is not synonymous with "darkness" -- if the sun comes up at 6AM and you leave for work at 8AM, you've had two hours of sunlight to charge your car while it was parked in your garage, and there are computers that can automate this.
> If you've got 50GW deficit over a week of cloud cover you need 4,200 GWh of storage to offset that.
Or 50GW of peaker plants, or 40GW of peaker plants and 20% of that amount of storage.
> And energy demand is much higher than 120 GW.
These are just example numbers for a hypothetical grid with 100GW of average demand.
> It's enough to satisfy 70% of the demand at 8PM.
In California, in October. Not in Texas in July.
> And since nuclear is just as cheap to run at 100% capacity all day long, it's better to scrap the bulk of your renewables because the nuclear plants make them redundant.
Nuclear is base load. It can make sense to build as much of it as there is base load demand, i.e. the minimum demand during any part of the day. But what do you want to do about the higher demand periods? Build extra nuclear plants that only operate 4 hours a day? Use battery storage with nuclear, even though that's way more expensive than battery storage with renewables?
> This depends on geography. On the west coast, it's the opposite: wind produces the least energy during winter.
The west coast has mild winters and thus less heating demand.
> A supercharger adds 200 miles of range in 15 minutes. You go into the shop, plug into the charger in the parking lot and when you come back out in 15 minutes you don't have to charge again until tomorrow.
Except very few parking lots have superchargers. And those that do, usually have just 5 or 10 for a parking lot of hundreds of spaces. This whole idea that a grid operator is going to accept that traffic conditions are going to potentially cause blackouts is not where near feasible.
> Or 50GW of peaker plants, or 40GW of peaker plants and 20% of that amount of storage
Right so ultimately the solution is: keep using fossil fuels. Great...
And a 10GW deficit over a week is still 1,680 GWh of storage. This is massive several times annual global battery production.
> Notice also that "overnight" is not synonymous with "darkness" -- if the sun comes up at 6AM and you leave for work at 8AM, you've had two hours of sunlight to charge your car while it was parked in your garage, and there are computers that can automate this.
Solar output is sinusoidal. Right after sunrise is still producing nearly zero energy.
> Nuclear is base load. It can make sense to build as much of it as there is base load demand, i.e. the minimum demand during any part of the day.
Base load is the significant majority of the electricity demand. It's not a small part of electricity demand, it's almost all of it.
> The west coast has mild winters and thus less heating demand.
Uh no? Maybe in California, but here in Seattle we regularly see nighttime temperatures below freezing.
> Except very few parking lots have superchargers. And those that do, usually have just 5 or 10 for a parking lot of hundreds of spaces.
The number of chargers increases with the number of cars.
> This whole idea that a grid operator is going to accept that traffic conditions are going to potentially cause blackouts is not where near feasible.
Pricing determines demand. Charging at the supercharger at the mall during sunlight is cheap so people go out of their way to do it, and the mall loves this because people come to the mall and buy things when they know it's a quick and cheap place to charge.
> Right so ultimately the solution is: keep using fossil fuels. Great...
Cloudy for an entire week happens, but it's rare. So 98% of the time you use nuclear and solar, then one week out of the year you use nuclear and fossil fuels instead, and you've got a 99% decarbonized grid.
Or you find something to burn instead of natural gas. You could quite plausibly have a one-week supply of biofuels or synthetic fuel, since it's for emergency use rather than everyday generation.
> And a 10GW deficit over a week is still 1,680 GWh of storage. This is massive several times annual global battery production.
Yeah, batteries don't really work for long-term storage. But the amount of batteries you need to avoid running the peaker plants on a normal day, combined with running the peaker plants 24 hours a day instead, gets you through a period of two or three days of low generation.
At that point you're doing demand suppression through pricing and things, but only when the period of low generation lasts for many contiguous days. And getting 50% demand suppression probably isn't reasonable, but 10% is, especially when you only rarely have to do it.
> Solar output is sinusoidal. Right after sunrise is still producing nearly zero energy.
"Right after sunrise" is nearly zero, but two hours after sunrise is more than 50% of peak.
And human activity is sinusoidal too. You start getting some solar generation before anybody is awake and you can put it into charging vehicles. Generation increases as more people start to wake up. Moreover, some people leave for work at 8AM, some leave at 9AM, some will charge at work or the mall, so you're still spreading the load throughout the daylight hours rather than trying to fit everything into the period immediately after sunrise.
> Base load is the significant majority of the electricity demand. It's not a small part of electricity demand, it's almost all of it.
Peak load in summertime is nearly double the base load.
> Uh no? Maybe in California, but here in Seattle we regularly see nighttime temperatures below freezing.
The average winter temperature in California is 46 degrees F, and California is >75% of the population of the west coast. The average winter temperature in Washington state is 33 degrees. The average winter temperature in New York, despite a more southern latitude than Washington, is 23 degrees. In North Dakota, still slightly south of Washington, it's 12.
The west coast has mild winters and less heating demand.
It also has a ton of existing hydro and existing high voltage transmission lines because the hydro is in the northwest but powers much of California, so you could fill California to the brim with renewables and then use the existing hydro as your batteries.
That's a pretty reasonable assumption once electric cars are the majority of cars.
> and don't commute very far.
There are popular electric cars with a range on the order of 300 miles. The average commute is 41 miles round trip.
> Also, there's loads of people doing errands during the day, or utility vehicles transporting cargo.
The average person does not drive 300 miles a day in total, and so does not need to charge more than once a day in total. Utility vehicles will have larger batteries and more range, and will strongly prefer to charge during daylight because charging from solar will cost less.
> And lastly, few grid operators are going to accept that their grid storage may drive away on masse during the holidays.
It's storing the energy that the vehicle itself will use. If the vehicle leaves the area then so does its demand for electricity.
> During a cloudy week, you're going to have a shortfall all the time. Solar drops to 10-25% effectiveness with cloud cover
If your grid has 40GW of nuclear and 60GW average of solar (which generates 120GW during daylight) then the 120GW drops to 30GW and you have 70GW of generation, which could be less than the demand before noon. You can also run the peaker plants even though you already had a surplus in those hours so you can put even more into the batteries to have enough later in the day.
> But again, peak demand isn't at midnight it's at 8pm. You can't just hand-wave away the challenge of meeting peak demand when intermittent sources aren't producing.
Suppose you have enough nuclear to meet the demand at midnight, which is enough to meet half of the demand at 8PM. So now you need to satisfy the other half from batteries for four hours, because before 6PM the sun is still up and after 10PM the demand falls off to what you're getting from nuclear. So you don't need enough batteries to satisfy all of the demand for the 12 hours when there is no sunlight, you only need enough to satisfy half of the demand for those four hours.
> And it aligns even worse during the Winter: solar is producing the least amount of energy, cloud cover is at its greatest extent.
But there is more wind in the winter, and at night, when there is more demand for heating.
And one of the ways to decarbonize heating in cities is nuclear with cogeneration. Then you're not using electricity for heat, you're using the waste heat from the reactors, which chops off a large chunk of even the existing nighttime load.