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Interesting brochure coming from Southampton University today: "Please don't buy an Electric car." The brochure is for their Electronic and Electrical Engineeri

by jansho 9y ago

Interesting brochure coming from Southampton University today: "Please don't buy an Electric car." The brochure is for their Electronic and Electrical Engineering programme. "Did you know that if 1/3 of us charged our current petrol cars for comparable electric vehicles and plugged them in to charge overnight, then the electricity supply network couldn't cope and we'd either have power cuts or may be told to switch everything off?" Then it explains: "Currently all our power stations (UK), working flat out, can generate about 70 GW electricity and this figure is dropping as older and less efficient stations are closed down. "Imagine 10 million cars all charging at the same time - that's already 80,000 million watts - more than we can generate. We'd have to switch off everything in our houses and keep the power stations all on full power!" Edit typo.

hawkice 9y ago
I mean, I'm not entirely sure that moving from millions of small gas/diesel generators (which is, functionally, what modern cars are) to using the grid should be bashed because the current grid can't support it. That seems like a fully general argument against change. For instance, no one claims you shouldn't vote because, if everyone voted, then Americans would have intolerable wait times at polling places (they wouldn't handle that volume). It's true, but I think the expectation is that we'd expand capacity. At least power generation (unlike voting) is done for profit, so I don't see the concern.
- jansho 9y ago
  > the expectation is that we'd expand capacity Yes but electric cars are often touted to be the "green solution". What's the point if we're just going to have more - and we're talking about lots more - power stations? They still eat resources, and spout pollution. There's the nuclear option but hey..
  - derefr 9y ago
    The thing you have to keep in mind is that, almost always, the bigger a generator is, the more efficient it is. Even if everyone's petrol-burning cars were swapped out for electric ones that were just as energy-intensive (i.e. required the same amount of joules of converted energy, to go the same distance, that petrol vehicles do) and then we took all that petrol, and burned it in a few big power-plants to generate that electricity... we'd still end up using less petrol. Because the big power plant would be far more efficient, in almost every sense, than the small ones in our cars. (Including senses like "sequesters more CO2.") And that's a pessimized case; in reality, electric cars get far better "miles per gallon" (more literally, miles per megajoule of stored energy) than petrol cars do. Look at (https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equivalent#Examples https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equi...): if you converted one gallon of gasoline into electricity using a regular, inefficient petrol car engine, and then charged an electric car's batteries using that generated power, the electric car would go quite a bit further than the same amount of stored energy would have taken the petrol car. (This being what hybrid cars do: use a regular petrol engine to charge batteries, and then run off those batteries.) The two factors combined mean that there is every reason to centralize the generation of electricity. Even if we still burn petrol to generate all that electricity (unlikely), we'd still be burning far less petrol.
    - jansho 9y ago
      Thanks for this. I do like the idea of centralising the generation of electricity. But while I understand the economies of scale aspect, I still think that we may be over-simplifying the whole picture. Sure, we may have greener cars. But what are the costs of this? You know we're talking about changing the whole infrastructure - and that's messy, and painful, and can take many years. And there's a few other questions which are too loosely connected for now but nevertheless still quite nagging, like nuclear as a resource and the growing global population which inevitably means more drivers..
      - danans 9y ago
        > You know we're talking about changing the whole infrastructure - and that's messy, and painful, and can take many years. Not as painful as you might think, and it's already happening. At the home level, it's very straightforward to add a charging station to your house, and at the grid level utilities have been preparing for this for a while now, evidenced by the fact that they offer EV-specific rate plans to their customers. The harder part is public charging infrastructure, which is still too sparse, but it is less critical than gas stations because of home charging.
- Reason077 9y ago
  If all 26 million cars in the UK were replaced with electrics, overall grid demand would only increase by about 20%. Will the grid need to get smarter? Sure. Will we need to improve aspects of it in the coming years and decades to support electrification? Obviously. But the idea that the existing grid cannot be adapted to support widespread adoption of electric vehicles is absolutely false.
- hatsunearu 9y ago
  Hey, ho investment opportunity!
derefr 9y ago
How efficiently can an electric car be charged using a gasoline generator, anyway? If "1/3 of us charged our current petrol cars for comparable electric vehicles", there'd suddenly be a lot of gasoline sitting around doing nothing. We could always burn that while bringing more base-load capacity online. Sort of an 'electric-engine polyfill'. ;)
- Gibbon1 9y ago
  I'd assume you could power a combined cycle generator with whatever feed stocks go into making gasoline which gives you 54% total efficiency. Bonus turning oil into gasoline consumes energy.
- Reason077 9y ago
  It actually takes a lot of electricity to refine oil into gasoline. If we need less gasoline, then that's a lot of electricity freed up for general grid use. https://m.youtube.com/watch?v=BQpX-9OyEr4 https://m.youtube.com/watch?v=BQpX-9OyEr4
Reason077 9y ago
EVs won't all charge at the same time, any more than all petrol and diesel cars are filled up at the same time. Besides, EVs are essentially storage batteries on wheels. They can be configured to charge overnight when grid demand is low and supply is abundant. V2G technology will mean that they support the grid, not burden it. Electrical engineering programmes should be embracing EVs for exactly this reason - there are lots of really interesting challenges and problems to solve. But they certainly are not unsolvable, and by putting their heads in the sand, the University of Southampton just sound like backwards-looking luddites.
- danderino 9y ago
  "EVs won't all charge at the same time, any more than all petrol and diesel cars are filled up at the same time. " This isn't really true. I imagine most people would put them on charge after coming back from work or at night.
  - _ph_ 9y ago
    But there exists charge timers. You can plug in the car, it starts charging at a selected time. As soon as their count is noticeable, there will be incentives to have the energy suppliers determine the charging speed to stabilize networks and get cheaper rates.
  - Reason077 9y ago
    "I imagine most people would put them on charge after coming back from work or at night." That's true, and it would indeed present a significant problem as the early evening already represents a peak demand period on many grids. However: plugging in doesn't necessarily mean the same thing as charging. Pretty much any EV already supports scheduled charging. It's useful to take advantage of cheap off-peak energy rates that start around 10 or 11pm (here in the UK, you can get overnight off-peak rates that are about 30% the cost of a typical all-day or peak rate). The next step is to have the chargers (or the EVs themselves) interact with the grid so that they automatically slow or stop charging during peak periods, in exchange for some incentive from your utility company. There are already trials of these smart chargers going on with in places with high EV uptake like California and the Netherlands. Taking that concept further, V2G will mean that your car can not only stop charging during demand peaks but actually sell some energy back to the grid. If your car needed, say, to top up 20 kWh overnight, it could first sell 10 kWh to the grid, receiving a high peak-time feed-in credit, then "buy" 30kWh later in the evening when prices are much cheaper. The net result could mean that the overall cost of charging is much cheaper or even free! Finally, as EV range gets bigger, the need to actually charge every night less frequent. Where I live, there are several EVs that are typically parked on the street (without access to a charger) and only seem to get charged every week or so. The owners probably only average 10 miles or so a day so daily charging isn't really needed.
_ph_ 9y ago
I don't know the British numbers, but in Germany a car travels less than 50km per day on average, that would consume about 8kWh of electricity. You can load these 8kWh in about 8 hours at 1 kW, that is less than the load of a vacuum cleaner and much less than a kitchen stove. Incandescent lightbulbs used to consume up to 100w each. So I cannot see where a grid overload would come from, if e.g. the cooking times are mostly avoided. In general, as soon as there are enough electrical cars on the road to be noticed by the utility companies, there will be incentives to preferably load at times where the grid benefits from their consumption, as late at night, or when there is a surplus of solar energy. In this function, electrical cars can rather help supporting the grid stability.

by jansho 9y ago

hawkice 9y ago

I mean, I'm not entirely sure that moving from millions of small gas/diesel generators (which is, functionally, what modern cars are) to using the grid should be bashed because the current grid can't support it. That seems like a fully general argument against change. For instance, no one claims you shouldn't vote because, if everyone voted, then Americans would have intolerable wait times at polling places (they wouldn't handle that volume). It's true, but I think the expectation is that we'd expand capacity. At least power generation (unlike voting) is done for profit, so I don't see the concern.

jansho 9y ago
> the expectation is that we'd expand capacity Yes but electric cars are often touted to be the "green solution". What's the point if we're just going to have more - and we're talking about lots more - power stations? They still eat resources, and spout pollution. There's the nuclear option but hey..
- derefr 9y ago
  The thing you have to keep in mind is that, almost always, the bigger a generator is, the more efficient it is. Even if everyone's petrol-burning cars were swapped out for electric ones that were just as energy-intensive (i.e. required the same amount of joules of converted energy, to go the same distance, that petrol vehicles do) and then we took all that petrol, and burned it in a few big power-plants to generate that electricity... we'd still end up using less petrol. Because the big power plant would be far more efficient, in almost every sense, than the small ones in our cars. (Including senses like "sequesters more CO2.") And that's a pessimized case; in reality, electric cars get far better "miles per gallon" (more literally, miles per megajoule of stored energy) than petrol cars do. Look at (https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equivalent#Examples https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equi...): if you converted one gallon of gasoline into electricity using a regular, inefficient petrol car engine, and then charged an electric car's batteries using that generated power, the electric car would go quite a bit further than the same amount of stored energy would have taken the petrol car. (This being what hybrid cars do: use a regular petrol engine to charge batteries, and then run off those batteries.) The two factors combined mean that there is every reason to centralize the generation of electricity. Even if we still burn petrol to generate all that electricity (unlikely), we'd still be burning far less petrol.
  - jansho 9y ago
    Thanks for this. I do like the idea of centralising the generation of electricity. But while I understand the economies of scale aspect, I still think that we may be over-simplifying the whole picture. Sure, we may have greener cars. But what are the costs of this? You know we're talking about changing the whole infrastructure - and that's messy, and painful, and can take many years. And there's a few other questions which are too loosely connected for now but nevertheless still quite nagging, like nuclear as a resource and the growing global population which inevitably means more drivers..
    - danans 9y ago
      > You know we're talking about changing the whole infrastructure - and that's messy, and painful, and can take many years. Not as painful as you might think, and it's already happening. At the home level, it's very straightforward to add a charging station to your house, and at the grid level utilities have been preparing for this for a while now, evidenced by the fact that they offer EV-specific rate plans to their customers. The harder part is public charging infrastructure, which is still too sparse, but it is less critical than gas stations because of home charging.
Reason077 9y ago
If all 26 million cars in the UK were replaced with electrics, overall grid demand would only increase by about 20%. Will the grid need to get smarter? Sure. Will we need to improve aspects of it in the coming years and decades to support electrification? Obviously. But the idea that the existing grid cannot be adapted to support widespread adoption of electric vehicles is absolutely false.
hatsunearu 9y ago
Hey, ho investment opportunity!

derefr 9y ago

How efficiently can an electric car be charged using a gasoline generator, anyway? If "1/3 of us charged our current petrol cars for comparable electric vehicles", there'd suddenly be a lot of gasoline sitting around doing nothing. We could always burn that while bringing more base-load capacity online. Sort of an 'electric-engine polyfill'. ;)

Gibbon1 9y ago
I'd assume you could power a combined cycle generator with whatever feed stocks go into making gasoline which gives you 54% total efficiency. Bonus turning oil into gasoline consumes energy.
Reason077 9y ago
It actually takes a lot of electricity to refine oil into gasoline. If we need less gasoline, then that's a lot of electricity freed up for general grid use. https://m.youtube.com/watch?v=BQpX-9OyEr4 https://m.youtube.com/watch?v=BQpX-9OyEr4

Reason077 9y ago

EVs won't all charge at the same time, any more than all petrol and diesel cars are filled up at the same time. Besides, EVs are essentially storage batteries on wheels. They can be configured to charge overnight when grid demand is low and supply is abundant. V2G technology will mean that they support the grid, not burden it. Electrical engineering programmes should be embracing EVs for exactly this reason - there are lots of really interesting challenges and problems to solve. But they certainly are not unsolvable, and by putting their heads in the sand, the University of Southampton just sound like backwards-looking luddites.

danderino 9y ago
"EVs won't all charge at the same time, any more than all petrol and diesel cars are filled up at the same time. " This isn't really true. I imagine most people would put them on charge after coming back from work or at night.
- _ph_ 9y ago
  But there exists charge timers. You can plug in the car, it starts charging at a selected time. As soon as their count is noticeable, there will be incentives to have the energy suppliers determine the charging speed to stabilize networks and get cheaper rates.
- Reason077 9y ago
  "I imagine most people would put them on charge after coming back from work or at night." That's true, and it would indeed present a significant problem as the early evening already represents a peak demand period on many grids. However: plugging in doesn't necessarily mean the same thing as charging. Pretty much any EV already supports scheduled charging. It's useful to take advantage of cheap off-peak energy rates that start around 10 or 11pm (here in the UK, you can get overnight off-peak rates that are about 30% the cost of a typical all-day or peak rate). The next step is to have the chargers (or the EVs themselves) interact with the grid so that they automatically slow or stop charging during peak periods, in exchange for some incentive from your utility company. There are already trials of these smart chargers going on with in places with high EV uptake like California and the Netherlands. Taking that concept further, V2G will mean that your car can not only stop charging during demand peaks but actually sell some energy back to the grid. If your car needed, say, to top up 20 kWh overnight, it could first sell 10 kWh to the grid, receiving a high peak-time feed-in credit, then "buy" 30kWh later in the evening when prices are much cheaper. The net result could mean that the overall cost of charging is much cheaper or even free! Finally, as EV range gets bigger, the need to actually charge every night less frequent. Where I live, there are several EVs that are typically parked on the street (without access to a charger) and only seem to get charged every week or so. The owners probably only average 10 miles or so a day so daily charging isn't really needed.

_ph_ 9y ago

I don't know the British numbers, but in Germany a car travels less than 50km per day on average, that would consume about 8kWh of electricity. You can load these 8kWh in about 8 hours at 1 kW, that is less than the load of a vacuum cleaner and much less than a kitchen stove. Incandescent lightbulbs used to consume up to 100w each. So I cannot see where a grid overload would come from, if e.g. the cooking times are mostly avoided. In general, as soon as there are enough electrical cars on the road to be noticed by the utility companies, there will be incentives to preferably load at times where the grid benefits from their consumption, as late at night, or when there is a surplus of solar energy. In this function, electrical cars can rather help supporting the grid stability.