Electric vehicles/Fossil fuel powered

If you charge an electric car with electricity that was generated by fossil fuels, is it as bad for the environment as driving a gas car?

Short answer

Yes.

The carbon emissions are almost exactly the same for electricity generated by

coal power plants
simple natural gas power plants

For advanced natural gas power plants, which are more efficient, best-case carbon emissions are still more than half of what they'd be from driving a gas car.

Long answer

For coal power plants:

electric_car.efficiency

100 miles per 34.6 kWh

The "gas mileage" equivalent for an average electric car.

Average Electric Car kWh Per Mile [Results From 231 EVs]
ecocostsavings.com › average-electric-car-kwh-per-mile

li_ion.charge_discharge_efficiency

85%

When you charge a lithium-ion battery, this much of the energy can be recovered. The rest is lost as heat.

Range: 80 to 90 %
from wikipedia; haven't found original source yet

power_grid.losses

5%

Electricity lost in transmission & distribution

Frequently Asked Questions (FAQs) - U.S. Energy Information ... - EIA
www.eia.gov › tools › faqs › faq
Nov 4, 2021 · "The U.S. Energy Information Administration (EIA) estimates that electricity transmission and distribution (T&D) losses equaled about 5% of ..."

coal_power_plant.efficiency

33%

How much of the coal's heat energy becomes electricity

Transformative Power Systems | Department of Energy
https://www.energy.gov/fecm/transformative-power-systems

car.fuel_economy

25.4 miles per gallon gasoline

Gas mileage of an average American new car

This datapoint is conformable with [electric_car.efficiency], because the calculator understands 'gallon gasoline' as an energy unit.

Citation:
"The average fuel economy for new 2020 model year cars, light trucks and SUVs in the United States was 25.4 miles per US gallon (9.3 L/100 km)."
- Fuel economy in automobiles - Wikipedia

car.fuel_economy fuel_economy_if_coal (calculation loading)

For natural gas power plants:

Some have the same efficiency as coal power plants (33%). Results would be about the same as above. (...)( Although in theory, coal and natural gas have different GHG emissions per unit energy(...)( which we didn't factor in, and maybe we should for best precision ) - in practice, they're about the same, due to natural gas#fugitive emissions. Both are close enough to gasoline, for the purpose of the calculations on this page. )

Other natural gas power plants (the more advanced "combined-cycle" type) are more efficient: up to 60%:

natural_gas_combined_cycle_power_plant.efficiency

60%

How much of the natural gas's heat energy becomes electricity, in an advanced "combined cycle" power plant

This is considered a "maximum" value - the best natural gas power plants achieve this.
Simpler/older natural gas plants (no combined cycle) have only an efficiency of 33%, same as [coal_power_plant.efficiency].

Read more: https://energyeducation.ca/encyclopedia/Natural_gas_power_plant

car.fuel_economy fuel_economy_if_advanced_natural_gas (calculation loading)

ev.battery

65.2 kWh

Energy capacity of the average electric vehicle battery

Useable battery capacity of full electric vehicles
https://ev-database.org/cheatsheet/useable-battery-capacity-electric-car

li_ion.ghg_by_energy

73 kg / kWh

Greenhouse gas emissions (CO2eq) of producing a lithium-ion battery

"by energy" here means "by the size of the battery, defined by how much energy can be stored".

What is the environmental impact of lithium batteries? - Changeit ...
changeit.app › blog › 2021-03-26-environmental-impact-of-lithium-batteries

gasoline.ghg_by_energy

71.30 kg / million btu

CO2 emissions of burning gasoline

https://www.eia.gov/environment/emissions/co2_vol_mass.php

ev.lifespan

8 years

Expected lifespan of an electric vehicle

Batteries usually are the component that wears out first.

average_us_vehicle.mileage_by_time

32 miles/day

Distance driven by the average American vehicle

Top Numbers Driving America's Gasoline Demand
https://www.api.org/news-policy-and-issues/blog/2022/05/26/top-numbers-driving-americas-gasoline-demand

car.fuel_economy

25.4 miles per gallon gasoline

Gas mileage of an average American new car

This datapoint is conformable with [electric_car.efficiency], because the calculator understands 'gallon gasoline' as an energy unit.

Citation:
"The average fuel economy for new 2020 model year cars, light trucks and SUVs in the United States was 25.4 miles per US gallon (9.3 L/100 km)."
- Fuel economy in automobiles - Wikipedia

So far, we still haven't counted the environmental impact of making an electric car, which is significantly more than for a gasoline-powered car:

For simplicity sake, we're just going to count the emissions of making the batteries, and assume that making the rest of the car would take roughly the same emissions as making a gasoline-powered vehicle: (...)( Technically, the assumption is that the emissions divided by lifespan are about the same. Gasoline vehicles are more complex than batteryless EVs, but also have a longer lifespan. ):

Estimate for lithium-ion electric cars: tonnes / year battery_ghg (calculation loading)

Now compare for the gasoline a non-electric car would burn, on average: tonnes / year gasoline_ghg (calculation loading)

Now, for coal power plants charging EVs, same amount of driving: tonnes / year coal_ghg (calculation loading) Imprecision note: (...)( This currently uses gasoline.ghg_by_energy when it should use coal.ghg_by_energy. The differences are minor though. )

Now, for advanced natural gas power plants charging EVs, same amount of driving: tonnes / year advanced_natural_gas_ghg (calculation loading) Imprecision note: (...)( This currently uses gasoline.ghg_by_energy when it should use (natural_gas.ghg_by_energy + natural_gas.fugitive_ghg_by_energy). The differences are minor though. )

Add the battery emissions: battery_ghg + coal_ghg tonnes / year total_ghg_if_coal (calculation loading)

battery_ghg + advanced_natural_gas_ghg tonnes / year total_ghg_if_advanced_natural_gas (calculation loading)

Now, for the final comparison: total_ghg_if_coal % gasoline_ghg (calculation loading)

total_ghg_if_advanced_natural_gas % gasoline_ghg (calculation loading)

Thus, emissions are about the same for coal as gasoline-powered cars. Emissions are only a bit better for advanced natural gas power plants. Also this doesn't count the other environmental impacts (non-CO₂) of mining lithium & cobalt.

Maybe there would be a good case for fossil-fuel-electricity-powered vehicles if carbon capture and storage could be fully & safely applied to the power plants.

Short answer

Long answer

See also