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Comment by simplicio | Hacker News Reader

Baseline power is less of an issue for EVs, since they a) have their own energy storage built in, and b) generally just run ~ 1 hour a day, making it pretty easy to come up with schemes to shift demand around.

Agree the trend of decommissioning nuclear plants is counterproductive for other reasons though.

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> Baseline power is less of an issue for EVs, since they a) have their own energy storage built in, and b) generally just run ~ 1 hour a day, making it pretty easy to come up with schemes to shift demand around.

Is that really true when much of the employed population falls on a relatively uniform commute schedule?

I'd expect similar congestion to what's seen on roadways to recur on an inadequate power grid.

Yes it's still true. To charge an EV the average person needs around 10kWh a day, distributed over 23h of parking time. That's not a lot of current. You just need to teach the car to talk to the grid so that not all cars charge at once.

The median driving distance in the EU is 30 km. The electric cars on sale use 15-20 kWh per 100 km. Thus daily routine per median will be 5-7.5 kWh. The current will be even less than the parent’s statement.

I recall a study that if 80% of cars were electric in the U.K., it will increase the load on the grid by 10-20%.

23h? That strikes me as ridiculously optimistic on a population-scale level.

When only charged at home it's just an overnight charging window.

Cars are parked about 23h a day. Eventually most parking spots will also have a charger, because that's pretty much the only way EVs will be adopted in cities where people don't have garages.

I'm not sure how this looks WRT grid limits/congestion, but there's an alternative mass-adoption scenario where battery tech matures to the point of charge rates becoming equal or better than "gassing up" today.

We don't have gas pumps at every parking spot and drivers are generally content with the current situation.

Ah yes, that's of course also possible, but I think it's a lot less likely, because the shift to EVs needs to happen quite quickly, imho before batteries had time to improve sufficiently.

Anyone having charger at home will never voluntarily connect the charger at work or in town unless they actually are desperate for charge.

Why?

Also, most people live in cities. Most people in cities don't have a charger at home.

Most people in cities don't have cars at all. They use public transportation or ride sharing. Parking a car in a city is expensive, especially since you need to park it both at home and at your destination.

Cities are full of cars during the day, but the parking lots empty out at night. They live in less-dense suburbs, where it's comparatively easy to park and comparatively easy to have a charger installed. In the city, many of those who are willing to afford a car at all will also find ways to charge it (including sharing a few charging stations at their garage).

1. It is a hassle with no benefit.

2. At least one but perhaps several orders of magnitudes more expensive than doing it at home. In part because you can charge overnight when pricing is the lowest.

I'd guess most people that have a EV-vehicle have a charger at home.

Both points are true today, but need not be true in the future. If everyone plugging in and charging at 20kW around 6pm becomes a problem (at it probably would be one), then the incentives will change.

I guess I'm mostly worried about the wind power trend.

a) Politicians love them

b) Politicians really don't understand power grids

c) They don't seem to be that "green", after all, if you consider the life span and the co2 emissions from the concrete manufacturing.

Not green? Really? Anything here change your mind:

https://www.factcheck.org/2018/03/wind-energys-carbon-footpr...

Wind is dynamic generation - that means there is a likelihood within the system where there is a backup generation when wind is not blowing. I am not expert, but the way Grid works, you cannot simply pick the wind farm, you have to have a systems view of the wind farm and how its back-up (likely NG generator) interact as a whole and does wind blow during the high demand etc. Wind at right places is excellent but outside of those geographic areas its a dead end. Also, windy places tend to be farther from where the demand is and you have to include transmission related expenditure. I think 500 mile distance is more or less rule of thumb considered not good, economically or environmentally.

A metaphor if I may engage, is you cannot get a six pack with pure calorie counting, you have to have a bit more sophisticated system in nutrition and work outs for that. Same thing applies for The Grid, a wind mill of same specification at two different locations will give different yields, at different time of day and have completely different effect on system as a whole.

If the next-best alternative on point (c) was nuclear, nuclear is probably less polluting. But since nuclear is off the table, since people react really poorly to rare events that cause towns to be uninhabitable, the next-best for (c) is going to be natural gas or another fossil source. I'll take wind any day.

I read an essay talking about another field where the authors conclusions apply to nuclear vs wind and solar.

He participated in research on low cost rocket designs. His take away was the actual design wasn't as important as building more rockets rather than less.

With solar you make panels by the 100 million. Wind turbines by the tens of thousand. Nuclear by the low digits. Per year.

There are a number of people who do understand how grids work who still love wind and solar.

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