Leawood911:
Whoopsy:
964C2:

What happens to your electric grid when you plug-in, for example, 100 million EV's every night, your infrastructure better be ready!

 

To some pipedream believers, we already have more than enough off peak capacity to charge all of them many times over.

The math is extremely simple and basic, but for some they claim the calculation is wrong.

Back to the fact that people don’t drive enough and cars don’t charge fast enough at home in order to make a dent during off peak hours.  You have this vision of everyone DC charging at home in 60 minutes after a 300 mile day. The reality is that perhaps %5 of your total monthly bill might be car charging.  It would not even matter if you did this off peak but if you did I doubt, compared to peak use during the day, it would be anywhere near the grid challenge you think it would be.  But - as eyes open to the vast battery on wheels which will outlast the wheels by a factor of 10 - the ability for that battery to serve as home energy storage and grid hardening is obvious.  In fact it is key to solar and other renewable energy. Homes can power up when power is cheap and use it when most needed.  This is so obvious I hate to keep pointing it out. 

 

Again, it's simple math buddy. Right now, EVs are still a tiny fraction of the overall car market. The drain on the grid is still negligible. 

Just in the USA alone, about 100 million cars are driven every day. Every year, the world's car production is just under 100 million.

Using that 100 million number. Each car gets plugged in at home to a home charger after work, that's 100 million times 7-9kW/hr per car. Works out to be 800,000,000,000,000W/hr, that's 800 GW, Giga-Watt. That's the output of 800 nuclear power stations. 

So not all of them needs a full 8-10hr charge, but all chargers works the same and negotiate the fastest charge rate first then ramp down depending on state of charge, so the instantaneous load right after work would still be roughly the same but the load would ramp down the later the night goes as chargers are ramping down their charge rate based on SoC. Some cars might only need a 30 min charge, others might need a couple hours, others could be a 4-6 hour charge. 

To ease the strain, government could mandate smart chargers and control their charge rate to not overload the grid, but who gets to decide which charge has charging privilege for faster rate? If I am your neighbor, why are you getting the full 9kW and I am throttled to only 3kW even if we plugged in at the same time?

These loads are on top of whatever household is using without EVs. 

Now for your other pipe dream about 'battery wall' energy storage, how many homes have it and how many don't yet? We are still decades away from widespread adoption.

 

 

 

 


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