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In Germany the government asked people not to use electric heaters this winter because the grid could break down. An ev drains way more power then a 2kw space

In Germany the government asked people not to use electric heaters this winter because the grid could break down. An ev drains way more power then a 2kw space heater.

Semaphor 4y ago
Well, yes. If tomorrow everyone replaces their ICE cars with EVs, then the grid won’t be able to handle that. Completely different situation, though.
- hasmanean 4y ago
  We should not replace ICE cars with EVs, but something smaller. Steam engines were large because that was how they got efficiency up. ICE cars could afford to be smaller and more efficient. If they had just replaced steam locmotives with diesel ones that would have been stupid...instead they built a whole new infrastructure around smaller cars that was much better than the rail network and redesigned our entire cities. Existing cars are the optimal configuration for a given engine cost and gas price. Electric motors are even more efficient, but using them in the form factor of a car is also stupid. With robotics we can now make tiny self-driving vehicles that can do chores for us. Why should I drive a 2-ton car to the store to pick up a gallon of milk, when the store can send a small robot to deliver it to me? Similarly a large empty bus can be replaced with smaller ATV sized EVs that drive me from my house to the main artery and merge to form one train. That reduces the size of the EV engine and battery pack by 10x. Some of the problems to be solved are not merely technological but organizational and cultural.
  - vfclists 4y ago
    Why should the store send a small robot to deliver it you? You can ride a bicycle to the store to pick it up. Just think of the cardiovascular benefits. And you know what? Think of the energy cost of the robot's manufacture, and the energy the delivery takes.
    - decafninja 4y ago
      Because rain, snow, heat, lack of fitness, security, amongst other reasons. Cycling is my most common mode of transportation these days. I love it. But I also know it's not going to be practical primary means of transport for a huge slice of the population. And the "danger from cars" ranks pretty low in my list of reasons.
    - hasmanean 4y ago
      A bike cannot compete in terms of energy efficiency with a slow robot that delivers multiple packages to people along a route. Human food is the most expensive fuel on the planet when you factor in agriculture.
Retric 4y ago
An average EV averages far less power than an average 2kW space heater over time. A 2kW space heater used just 12 hours a day uses the same power per day as 4 mile per kWh EV driven 35,000 miles per year. Many space heaters see more than 12h/day of use but 35k miles per year is extremely rare. EV’s are like microwaves, they use a lot of power when on but the grid cares about average load across millions of them not what’s happening in any one home.
- jodrellblank 4y ago
  > “as a 4kWh/mile EV” “The battery size for a Tesla Model 3 ranges from 50 kWh to 82 kWh” that would give the largest a range of 20 miles. Ev-database.org says they use 151Wh/km which is about 240Wh/mile.
  - Retric 4y ago
    Just a typo. A reasonably efficient EV is 240Wh/mile or ~4 miles per kWh.
D13Fd 4y ago
This is a ridiculous comparison. Google tells me an electric vehicle uses around 14kWh per day if you drive ~14k miles per year, and is much more efficient than an internal combustion engine. Your hypothetical 2kw space heater uses 24kWh a day and is drastically less efficient than a heat pump.
- kybernetyk 4y ago
  Peak loads let the grid collapse. Not constant loads over N hours. If everyone starts charging their EVs at roughly the same time (like when getting home from work) it won't matter that the EV uses less power over 24hours than a space heater. EV zealots are just blind to the issues their silver bullet creates. Just like the "walk-able cities" folks.
  - theshrike79 4y ago
    This is why we have different pricing for different hours. Only those that actually need the capacity will use the expensive power from 16-20. Others will use dirt-cheap night time electricity. And with Vehicle to Grid smart people can sell the extra energy in their car battery during peak hours and use the credits from that to charge their car overnight. None of this is some kind of magical tech that's hard to use. Gridio (https://www.gridio.io https://www.gridio.io) already exists and works directly with multiple EV brands.
raisedbyninjas 4y ago
It looks like Germans drive an average of 19 miles per day. Charging an EV to cover that would only need 7kwh at 100% efficiency. So a space heater could use more or less overnight depending on its duty cycle.
themitigating 4y ago
A Tesla Model 3 charges at the rate of 3~ per hour using about 1.2 kw. Over 12 hours that's about 36 miles each night.
theshrike79 4y ago
My EV is currently charging at 2.4kW power. Or was, I'm pretty sure the battery was already at limit a few hours ago. The next time I need to plug it in is maybe on Saturday. You need to use your electric heater 24/7 to not freeze.

In Germany the government asked people not to use electric heaters this winter because the grid could break down. An ev drains way more power then a 2kw space heater.

Semaphor 4y ago

Well, yes. If tomorrow everyone replaces their ICE cars with EVs, then the grid won’t be able to handle that. Completely different situation, though.

hasmanean 4y ago
We should not replace ICE cars with EVs, but something smaller. Steam engines were large because that was how they got efficiency up. ICE cars could afford to be smaller and more efficient. If they had just replaced steam locmotives with diesel ones that would have been stupid...instead they built a whole new infrastructure around smaller cars that was much better than the rail network and redesigned our entire cities. Existing cars are the optimal configuration for a given engine cost and gas price. Electric motors are even more efficient, but using them in the form factor of a car is also stupid. With robotics we can now make tiny self-driving vehicles that can do chores for us. Why should I drive a 2-ton car to the store to pick up a gallon of milk, when the store can send a small robot to deliver it to me? Similarly a large empty bus can be replaced with smaller ATV sized EVs that drive me from my house to the main artery and merge to form one train. That reduces the size of the EV engine and battery pack by 10x. Some of the problems to be solved are not merely technological but organizational and cultural.
- vfclists 4y ago
  Why should the store send a small robot to deliver it you? You can ride a bicycle to the store to pick it up. Just think of the cardiovascular benefits. And you know what? Think of the energy cost of the robot's manufacture, and the energy the delivery takes.
  - decafninja 4y ago
    Because rain, snow, heat, lack of fitness, security, amongst other reasons. Cycling is my most common mode of transportation these days. I love it. But I also know it's not going to be practical primary means of transport for a huge slice of the population. And the "danger from cars" ranks pretty low in my list of reasons.
  - hasmanean 4y ago
    A bike cannot compete in terms of energy efficiency with a slow robot that delivers multiple packages to people along a route. Human food is the most expensive fuel on the planet when you factor in agriculture.

Retric 4y ago

An average EV averages far less power than an average 2kW space heater over time. A 2kW space heater used just 12 hours a day uses the same power per day as 4 mile per kWh EV driven 35,000 miles per year. Many space heaters see more than 12h/day of use but 35k miles per year is extremely rare. EV’s are like microwaves, they use a lot of power when on but the grid cares about average load across millions of them not what’s happening in any one home.

jodrellblank 4y ago
> “as a 4kWh/mile EV” “The battery size for a Tesla Model 3 ranges from 50 kWh to 82 kWh” that would give the largest a range of 20 miles. Ev-database.org says they use 151Wh/km which is about 240Wh/mile.
- Retric 4y ago
  Just a typo. A reasonably efficient EV is 240Wh/mile or ~4 miles per kWh.

D13Fd 4y ago

This is a ridiculous comparison. Google tells me an electric vehicle uses around 14kWh per day if you drive ~14k miles per year, and is much more efficient than an internal combustion engine. Your hypothetical 2kw space heater uses 24kWh a day and is drastically less efficient than a heat pump.

kybernetyk 4y ago
Peak loads let the grid collapse. Not constant loads over N hours. If everyone starts charging their EVs at roughly the same time (like when getting home from work) it won't matter that the EV uses less power over 24hours than a space heater. EV zealots are just blind to the issues their silver bullet creates. Just like the "walk-able cities" folks.
- theshrike79 4y ago
  This is why we have different pricing for different hours. Only those that actually need the capacity will use the expensive power from 16-20. Others will use dirt-cheap night time electricity. And with Vehicle to Grid smart people can sell the extra energy in their car battery during peak hours and use the credits from that to charge their car overnight. None of this is some kind of magical tech that's hard to use. Gridio (https://www.gridio.io https://www.gridio.io) already exists and works directly with multiple EV brands.

raisedbyninjas 4y ago

It looks like Germans drive an average of 19 miles per day. Charging an EV to cover that would only need 7kwh at 100% efficiency. So a space heater could use more or less overnight depending on its duty cycle.

themitigating 4y ago

A Tesla Model 3 charges at the rate of 3~ per hour using about 1.2 kw. Over 12 hours that's about 36 miles each night.

theshrike79 4y ago

My EV is currently charging at 2.4kW power. Or was, I'm pretty sure the battery was already at limit a few hours ago. The next time I need to plug it in is maybe on Saturday. You need to use your electric heater 24/7 to not freeze.