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Peak usage is not a problem. Why should everyone charge from 6 to 8 pm? People will charge when electricity is cheapest. Also there are already discounted rates

by _ph_ 6y ago

Peak usage is not a problem. Why should everyone charge from 6 to 8 pm? People will charge when electricity is cheapest. Also there are already discounted rates for heat pumps where the utilities can control the running times to help balancing the net. Actually, electric cars will stabilize the grid by being charged automatically when the grid has a lot of supply and not when there is a shortage.

bonzini 6y ago
> People will charge when electricity is cheapest So if it's cheapest from 6 PM to 6 AM they will start charging (absent any control from the utility) at 6 PM approximately. I am interested (genuinely :-)) in standards for grid to appliance communication and on which countries have those discounted rates. Would I lose the discount if my commute is longer (so I need a continuous supply throughout most of the night)? Are they tied to specific wires coming in the building? Also did anybody run the numbers on the power that would be needed by a supercharger network comparable to current highway gas stations?
- _ph_ 6y ago
  There are already several standards in place for this. For many decades, the utilities send a signal modulated on the electricity line when cheaper "night" rates are available. This was created to increase the night load as the slow power stations struggled with reducing their power output. There was a special heating system designed to use this, which would heat up over night with cheap electricity and retain that heat for daytime heating. This signal could immediately be used for charging control. And of course the signal would be given only when there is more supply than demand. Certainly not at 6pm. But after 8pm private demand starts dropping strongly (which is mostly generated by cooking). Smart meters are also already deployed to offer time dependent rates, those could be used for smart charging and for heat pumps there is an active control channel for direct control by the utilities. All that is already in place. Of course this can be done selectively, so if needed, some cars could start charging at 8pm, others at 10pm and so on.

by _ph_ 6y ago

bonzini 6y ago

> People will charge when electricity is cheapest So if it's cheapest from 6 PM to 6 AM they will start charging (absent any control from the utility) at 6 PM approximately. I am interested (genuinely :-)) in standards for grid to appliance communication and on which countries have those discounted rates. Would I lose the discount if my commute is longer (so I need a continuous supply throughout most of the night)? Are they tied to specific wires coming in the building? Also did anybody run the numbers on the power that would be needed by a supercharger network comparable to current highway gas stations?

_ph_ 6y ago
There are already several standards in place for this. For many decades, the utilities send a signal modulated on the electricity line when cheaper "night" rates are available. This was created to increase the night load as the slow power stations struggled with reducing their power output. There was a special heating system designed to use this, which would heat up over night with cheap electricity and retain that heat for daytime heating. This signal could immediately be used for charging control. And of course the signal would be given only when there is more supply than demand. Certainly not at 6pm. But after 8pm private demand starts dropping strongly (which is mostly generated by cooking). Smart meters are also already deployed to offer time dependent rates, those could be used for smart charging and for heat pumps there is an active control channel for direct control by the utilities. All that is already in place. Of course this can be done selectively, so if needed, some cars could start charging at 8pm, others at 10pm and so on.