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Are there any credible sources that show Teslas as more environmentally friendly? Electric vehicles run on coal and natural gas to varyingly large extents.

by dilemma 10y ago

TeMPOraL 10y ago
They also run on nuclear power and wind power and solar power - it all depends on what a local power grid uses. But regardless, burning fuel at a power plant is much more efficient than doing it in an ICE, so even if Teslas were powered by gasoline, as long as it's burned at the central plant, it's more energy-efficient and better for the environment.
- wott 10y ago
  Uh? Straight fuel -> mechanical energy conversion is less efficient than a series of fuel -> heat -> mechanical energy -> electrical energy -> transportation -> storage -> mechanical energy conversions?
  - TeMPOraL 10y ago
    Yes, because ICEs are very inefficient compared to both electric motors and powerplant turbines. In the latter case, scale buys efficiency. And that's all before you factor in the transport costs of car fuel - gotta burn the fuel to move fuel to top up the gas stations, after all.
  - bkanber 10y ago
    Yes, it is, by a decent margin at that. ICEs have a peak efficiency of only about 30%, and average 15-20%. And that's just in the engine. Powertrain losses for ICE vehicles are a handful of percentage points higher than for EVs as well. Well-to-wheel efficiency for EVs is better than ICEs in every country except India currently.
  - leoedin 10y ago
    An internal combustion engine efficiency averages maybe 20% or so[1]. A combined cycle gas turbine power plant (running on natural gas) can reach 60% efficiency (it seems most operate a bit lower, but still in the high 50s)[2]. An electric car might be 60% efficient from the point grid power is delivered to the point it reaches the wheels.[1] That gives a natural gas -> power at wheels efficiency of 36%, or 1.8x the internal combustion engine. [1]: https://www.fueleconomy.gov/feg/evtech.shtml https://www.fueleconomy.gov/feg/evtech.shtml [2]: http://www.powerengineeringint.com/articles/print/volume-18/issue-3/features/ccgt-breaking-the-60-per-cent-efficiency-barrier.html http://www.powerengineeringint.com/articles/print/volume-18/...
__s 10y ago
Power plants are more efficient than a car's combustion engine, & power plants can change over time without changing the vehicle. Modular design ftw
- kitsunesoba 10y ago
  Yes precisely. The coal plants in a local grid can be swapped out for plants that generate power in any number of other ways. Furthermore, EVs can easily have their batteries replaced with other power storage methods should we figure out something that's safer/higher capacity/less toxic/etc. But an ICE vehicle will always be an ICE vehicle no matter how technology improves. As long as it exists and continues to be driven it's a constant burden on the environment.
- jernfrost 10y ago
  And a lot of todays power-plants can't regulate supply to meet demand easily so power is often wasted or sold at negative price. This is a particular problem at night time. With EVs charging at night one could handle excess power production without expanding total electric production in any way. EVs are simply a good match for the limitations of today's power production.
SEJeff 10y ago
And the gigafactory will be net zero or net negative due to renewables. Much of the environmental badness is due to manufacturing. That will be close to nil in comparison to a traditional factory for the Tesla vehicles.
greglindahl 10y ago
Here you go: http://www.ucsusa.org/clean-vehicles/electric-vehicles/life-cycle-ev-emissions http://www.ucsusa.org/clean-vehicles/electric-vehicles/life-... This is a short-sighted question, however. If I buy a new gasoline-powered car, it will pollute the same amount until it is crushed. If I buy a new EV, it gets cleaner over time as more renewables are added to the grid. It's not just a question of how clean the car is today.
- deleted 10y ago
  [deleted]
bkanber 10y ago
In every country except India, the well-to-wheel CO2 emissions for EVs beat gas ICEs. The problem is coal only, natural gas is pretty good. Even China now has enough non-coal energy sources to make EVs worth it. Source: I was a hybrid vehicle powertrain engineer.

Are there any credible sources that show Teslas as more environmentally friendly? Electric vehicles run on coal and natural gas to varyingly large extents.

by dilemma 10y ago

Are there any credible sources that show Teslas as more environmentally friendly? Electric vehicles run on coal and natural gas to varyingly large extents.

TeMPOraL 10y ago

They also run on nuclear power and wind power and solar power - it all depends on what a local power grid uses. But regardless, burning fuel at a power plant is much more efficient than doing it in an ICE, so even if Teslas were powered by gasoline, as long as it's burned at the central plant, it's more energy-efficient and better for the environment.

wott 10y ago
Uh? Straight fuel -> mechanical energy conversion is less efficient than a series of fuel -> heat -> mechanical energy -> electrical energy -> transportation -> storage -> mechanical energy conversions?
- TeMPOraL 10y ago
  Yes, because ICEs are very inefficient compared to both electric motors and powerplant turbines. In the latter case, scale buys efficiency. And that's all before you factor in the transport costs of car fuel - gotta burn the fuel to move fuel to top up the gas stations, after all.
- bkanber 10y ago
  Yes, it is, by a decent margin at that. ICEs have a peak efficiency of only about 30%, and average 15-20%. And that's just in the engine. Powertrain losses for ICE vehicles are a handful of percentage points higher than for EVs as well. Well-to-wheel efficiency for EVs is better than ICEs in every country except India currently.
- leoedin 10y ago
  An internal combustion engine efficiency averages maybe 20% or so[1]. A combined cycle gas turbine power plant (running on natural gas) can reach 60% efficiency (it seems most operate a bit lower, but still in the high 50s)[2]. An electric car might be 60% efficient from the point grid power is delivered to the point it reaches the wheels.[1] That gives a natural gas -> power at wheels efficiency of 36%, or 1.8x the internal combustion engine. [1]: https://www.fueleconomy.gov/feg/evtech.shtml https://www.fueleconomy.gov/feg/evtech.shtml [2]: http://www.powerengineeringint.com/articles/print/volume-18/issue-3/features/ccgt-breaking-the-60-per-cent-efficiency-barrier.html http://www.powerengineeringint.com/articles/print/volume-18/...

__s 10y ago

Power plants are more efficient than a car's combustion engine, & power plants can change over time without changing the vehicle. Modular design ftw

kitsunesoba 10y ago
Yes precisely. The coal plants in a local grid can be swapped out for plants that generate power in any number of other ways. Furthermore, EVs can easily have their batteries replaced with other power storage methods should we figure out something that's safer/higher capacity/less toxic/etc. But an ICE vehicle will always be an ICE vehicle no matter how technology improves. As long as it exists and continues to be driven it's a constant burden on the environment.
jernfrost 10y ago
And a lot of todays power-plants can't regulate supply to meet demand easily so power is often wasted or sold at negative price. This is a particular problem at night time. With EVs charging at night one could handle excess power production without expanding total electric production in any way. EVs are simply a good match for the limitations of today's power production.

SEJeff 10y ago

And the gigafactory will be net zero or net negative due to renewables. Much of the environmental badness is due to manufacturing. That will be close to nil in comparison to a traditional factory for the Tesla vehicles.

greglindahl 10y ago

Here you go: http://www.ucsusa.org/clean-vehicles/electric-vehicles/life-cycle-ev-emissions http://www.ucsusa.org/clean-vehicles/electric-vehicles/life-... This is a short-sighted question, however. If I buy a new gasoline-powered car, it will pollute the same amount until it is crushed. If I buy a new EV, it gets cleaner over time as more renewables are added to the grid. It's not just a question of how clean the car is today.

deleted 10y ago
[deleted]

bkanber 10y ago

In every country except India, the well-to-wheel CO2 emissions for EVs beat gas ICEs. The problem is coal only, natural gas is pretty good. Even China now has enough non-coal energy sources to make EVs worth it. Source: I was a hybrid vehicle powertrain engineer.