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We already have capacity for that much electricity generation. We'll have to be careful about managing the peak usage - smart chargers which can be remotely cut

We already have capacity for that much electricity generation. We'll have to be careful about managing the peak usage - smart chargers which can be remotely cut off will probably be mandatory. As an example, the UK grid yesterday saw a peak of about 30 GW, but was sitting at 20 GW for most of the night. (https://gridwatch.co.uk/ https://gridwatch.co.uk/). That's about 70 GWh of overnight capacity that could have been used (the grid has to be sized for peak loads). The average car in the UK drives about 7000 miles a year (https://www.bymiles.co.uk/insure/magazine/mot-data-research-and-analysis/ https://www.bymiles.co.uk/insure/magazine/mot-data-research-...). An average EV might get 3 miles per kWh. So the average car, on an average night, needs 20 miles of range - which is about 6.4kWh. Our grid excess capacity of 70 GWh means we can charge just under 11 million cars before we're using more than our current peak electricity demand. The UK grid is designed for more capacity than todays peak, though. The maximum delivered power in the last year was 47.275 GW. If we maximised the grid at that level all year we'd be adding an additional 17 GW compared to yesterday. That's 408 GWh, or enough power for an additional 63.7 million cars (on top of our 11 million) - a total of 74.7 million average cars. The UK currently has around 32.9 million registered cars. There is undoubtedly going to be hotspots which need more work, but overall the additional load of electric cars (with smart chargers which can shed load if needed) is within the limits of the current grid and generation capacity.

cataflam 5y ago
From your first link, isn't a lot of that difference between 30 GW peak and 20 GW at night due to solar? It seems to provide about 9 GW during the day, that removes most of your estimated 70 GWh of extra overnight capacity (unless I'm reading it wrong).
ppf 5y ago
> That's about 70 GWh of overnight capacity that could have been used...Our grid excess capacity of 70 GWh means we can charge just under 11 million cars before we're using more than our current peak electricity demand. You've ignored all losses. Transmission and distribution losses, the latter of which are worse for low-voltage customers (ie, domestic use, and is over 10%), total around 15% for domestic use. As well as that, charger loss is around 15%. Adding all that up, a car that needs 20 miles at 333 Wh/mile needs 9kWh of generated supply power, or barely 8 million cars (assuming this power is actually available). There is also the obvious problem that there is no solar availabe at night, which makes up a relatively large percentage of the UK's energy mix (over 8GW right now, as I just looked). >The maximum delivered power in the last year was 47.275 GW How much of that peak power was from peaking plants, for example, the 1.8GW pumped hydro storage at Dinorwic? A huge part of the problems with EVs are related to unrealistic and misleading estimates. Please be careful with the maths.
- leoedin 5y ago
  The comment you're replying to was in response to the parent comment, who said "Its not even clear how we are supposed to produce the necessary amounts of electricity" You can argue about efficiencies (which it's true, should be taken into account) - but the point remains. The current grid already has very close to the capacity required for electric cars. Maybe we'll need to add a few power stations or interconnects, maybe we'll need to upgrade some local infrastructure here or there, but it's not like we're an order of magnitude off. There's currently close to 100 GW of installed capacity on the UK grid (https://www.statista.com/statistics/496283/total-electricity-generation-capacity-uk/ https://www.statista.com/statistics/496283/total-electricity...) - even if you completely stripped out all the variable-supply renewables like solar and wind, you'd still be left with a substantial margin. There's no solar overnight - true - but there's also very little solar on dark cloudy December days (when demand is often high) and the grid manages to deliver ~40GW peak then without issues. The pumped storage couldn't have been more than 2.8GW - because that's how much is installed. In fact, apparently overall demand has dropped year on year - the overall peak was 62 GW, in 2002. At least in the UK, National Grid (the grid operator) agrees - https://www.nationalgrid.com/stories/journey-to-net-zero/5-myths-about-electric-vehicles-busted https://www.nationalgrid.com/stories/journey-to-net-zero/5-m.... There's not an issue with overall capacity.
  - ppf 5y ago
    No, it's not an order of magnitude, although I find it disingenuous to use the peak load from 20 years ago, when the UK National Grid has changed quite considerably since then, and has lost 16GW in production capacity [1] We're also apparently in the process of nuclear decomissioning, and I'm not sure where that lost power will come from. At the moment, we just ramp up gas-fired power stations to meet demand, so yes, we can just burn more gas to generate more power. In this scenario, transmission/distribution and charger losses wipe out a lot of the CO2 gains. We also haven't even touched on the idea of commercial EVs - I'm not sure of the figures, but I suspect that the energy requirements for making all vans, trucks, and lorries electrically powered will outstrip EV domestic usage (and, for that matter, should be more important from a CO2 reduction point of view). [1]https://en.wikipedia.org/wiki/List_of_power_stations_in_England https://en.wikipedia.org/wiki/List_of_power_stations_in_Engl...

cataflam 5y ago

From your first link, isn't a lot of that difference between 30 GW peak and 20 GW at night due to solar? It seems to provide about 9 GW during the day, that removes most of your estimated 70 GWh of extra overnight capacity (unless I'm reading it wrong).

ppf 5y ago

> That's about 70 GWh of overnight capacity that could have been used...Our grid excess capacity of 70 GWh means we can charge just under 11 million cars before we're using more than our current peak electricity demand. You've ignored all losses. Transmission and distribution losses, the latter of which are worse for low-voltage customers (ie, domestic use, and is over 10%), total around 15% for domestic use. As well as that, charger loss is around 15%. Adding all that up, a car that needs 20 miles at 333 Wh/mile needs 9kWh of generated supply power, or barely 8 million cars (assuming this power is actually available). There is also the obvious problem that there is no solar availabe at night, which makes up a relatively large percentage of the UK's energy mix (over 8GW right now, as I just looked). >The maximum delivered power in the last year was 47.275 GW How much of that peak power was from peaking plants, for example, the 1.8GW pumped hydro storage at Dinorwic? A huge part of the problems with EVs are related to unrealistic and misleading estimates. Please be careful with the maths.

leoedin 5y ago
The comment you're replying to was in response to the parent comment, who said "Its not even clear how we are supposed to produce the necessary amounts of electricity" You can argue about efficiencies (which it's true, should be taken into account) - but the point remains. The current grid already has very close to the capacity required for electric cars. Maybe we'll need to add a few power stations or interconnects, maybe we'll need to upgrade some local infrastructure here or there, but it's not like we're an order of magnitude off. There's currently close to 100 GW of installed capacity on the UK grid (https://www.statista.com/statistics/496283/total-electricity-generation-capacity-uk/ https://www.statista.com/statistics/496283/total-electricity...) - even if you completely stripped out all the variable-supply renewables like solar and wind, you'd still be left with a substantial margin. There's no solar overnight - true - but there's also very little solar on dark cloudy December days (when demand is often high) and the grid manages to deliver ~40GW peak then without issues. The pumped storage couldn't have been more than 2.8GW - because that's how much is installed. In fact, apparently overall demand has dropped year on year - the overall peak was 62 GW, in 2002. At least in the UK, National Grid (the grid operator) agrees - https://www.nationalgrid.com/stories/journey-to-net-zero/5-myths-about-electric-vehicles-busted https://www.nationalgrid.com/stories/journey-to-net-zero/5-m.... There's not an issue with overall capacity.
- ppf 5y ago
  No, it's not an order of magnitude, although I find it disingenuous to use the peak load from 20 years ago, when the UK National Grid has changed quite considerably since then, and has lost 16GW in production capacity [1] We're also apparently in the process of nuclear decomissioning, and I'm not sure where that lost power will come from. At the moment, we just ramp up gas-fired power stations to meet demand, so yes, we can just burn more gas to generate more power. In this scenario, transmission/distribution and charger losses wipe out a lot of the CO2 gains. We also haven't even touched on the idea of commercial EVs - I'm not sure of the figures, but I suspect that the energy requirements for making all vans, trucks, and lorries electrically powered will outstrip EV domestic usage (and, for that matter, should be more important from a CO2 reduction point of view). [1]https://en.wikipedia.org/wiki/List_of_power_stations_in_England https://en.wikipedia.org/wiki/List_of_power_stations_in_Engl...