Electric vehicles/Fossil fuel powered: Difference between revisions
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==Short answer== | ==Short answer== | ||
<big>'''Yes.'''</big> | |||
The carbon emissions, compared to a gas car, are approximately: | |||
* 135% for coal power plants | |||
The carbon emissions | * 89% for ''older'' natural gas power plants {{light|(more common)}} | ||
* coal power plants | * 56% for ''newer'' natural gas power plants {{light|(less common)}} | ||
* '' | |||
==Long answer== | ==Long answer== | ||
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}} | }} | ||
''For a gasoline car {{light|(typical | ''For a gasoline car'' {{light|(typical usage)}}: | ||
{{calc | {{calc | ||
|average_us_vehicle.mileage_by_time / car.fuel_economy * gasoline.ghg_by_energy | |average_us_vehicle.mileage_by_time / car.fuel_economy * gasoline.ghg_by_energy | ||
|tonnes/year | |tonnes/year | ||
| | |usage_emissions_if_gasoline_car | ||
}} | }} | ||
''For an EV charged by coal power plants {{light|(same amount of driving as above)}}: | ''For an EV charged by '''coal''' power plants'' {{light|(same amount of driving as above)}}: | ||
{{calc | {{calc | ||
|average_us_vehicle.mileage_by_time / electric_car.fuel_economy_equivalent * coal.ghg_by_energy / coal_power_plant.efficiency / (100% - power_grid.losses) / li_ion.charge_discharge_efficiency | |average_us_vehicle.mileage_by_time / electric_car.fuel_economy_equivalent * coal.ghg_by_energy / coal_power_plant.efficiency / (100% - power_grid.losses) / li_ion.charge_discharge_efficiency | ||
|tonnes/year | |tonnes/year | ||
| | |usage_emissions_if_EV_coal | ||
}} | }} | ||
''For an EV charged by natural gas power plants {{light|(same amount of driving)}}: | ''For an EV charged by '''natural gas''' power plants'' {{light|(same amount of driving)}}: | ||
{{calc | {{calc | ||
|average_us_vehicle.mileage_by_time / electric_car.fuel_economy_equivalent * (natural_gas.ghg_by_energy + natural_gas.fugitive_ghg_by_energy) / natural_gas_power_plant.efficiency / (100% - power_grid.losses) / li_ion.charge_discharge_efficiency | |average_us_vehicle.mileage_by_time / electric_car.fuel_economy_equivalent * (natural_gas.ghg_by_energy + natural_gas.fugitive_ghg_by_energy) / natural_gas_power_plant.efficiency / (100% - power_grid.losses) / li_ion.charge_discharge_efficiency | ||
|tonnes/year | |tonnes/year | ||
| | |usage_emissions_if_EV_natural_gas | ||
}} | }} | ||
''For an EV charged by | ''For an EV charged by advanced {{light|(combined-cycle type)}} natural gas power plants'' {{light|(same amount of driving)}}: | ||
{{calc | {{calc | ||
|average_us_vehicle.mileage_by_time / electric_car.fuel_economy_equivalent * (natural_gas.ghg_by_energy + natural_gas.fugitive_ghg_by_energy) / natural_gas_combined_cycle_power_plant.efficiency / (100% - power_grid.losses) / li_ion.charge_discharge_efficiency | |average_us_vehicle.mileage_by_time / electric_car.fuel_economy_equivalent * (natural_gas.ghg_by_energy + natural_gas.fugitive_ghg_by_energy) / natural_gas_combined_cycle_power_plant.efficiency / (100% - power_grid.losses) / li_ion.charge_discharge_efficiency | ||
|tonnes/year | |tonnes/year | ||
| | |usage_emissions_if_EV_advanced_natural_gas | ||
}} | }} | ||
'''Battery emissions''' <!-- not technically a heading. we don't want mediawiki to generate a table of contents. --> | '''Battery production emissions''' <!-- not technically a heading. we don't want mediawiki to generate a table of contents. --> | ||
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. | 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, let's | For simplicity sake, let's assume that ''batteries'' account for the entire difference between electric cars and gasoline cars, in terms of GHG emissions of ''production'' divided by vehicle ''lifespan''. {{x|A gasoline vehicle is a bit more complex than a batteryless EV, but the former also has a longer lifespan.}} | ||
{{dp | {{dp | ||
Line 211: | Line 209: | ||
'''''Now, for the final comparison:''''' | '''''Now, for the final comparison:''''' | ||
{{calc | {{calc | ||
| | |usage_emissions_if_EV_coal + battery_emissions | ||
|% | |% usage_emissions_if_gasoline_car | ||
}} | }} | ||
{{calc | {{calc | ||
| | |usage_emissions_if_EV_natural_gas + battery_emissions | ||
|% | |% usage_emissions_if_gasoline_car | ||
}} | }} | ||
{{calc | {{calc | ||
| | |usage_emissions_if_EV_advanced_natural_gas + battery_emissions | ||
|% | |% usage_emissions_if_gasoline_car | ||
}} | }} | ||
Thus, with coal power, emissions are worse than driving a gasoline-powered car. But for ''advanced'' natural gas power plants, emissions are about half. In either case, this doesn't count the other environmental impacts {{light|(non-CO<sub>2</sub>)}} of mining lithium & cobalt. | Thus, with coal power, emissions are ''worse'' than driving a gasoline-powered car. But for ''advanced'' natural gas power plants, emissions are about ''half''. In either case, this doesn't count the other environmental impacts {{light|(non-CO<sub>2</sub>)}} 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. | 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. |
Revision as of 01:36, 4 April 2023
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, compared to a gas car, are approximately:
- 135% for coal power plants
- 89% for older natural gas power plants (more common)
- 56% for newer natural gas power plants (less common)
Long answer
The following calculations compare the average gasoline-powered vehicle with the average lithium-ion battery-based electric vehicle. Greenhouse gas emissions are in tonnes CO2 equivalent (CO2eq):
Usage emissions
ecocostsavings.com › average-electric-car-kwh-per-mile
from wikipedia; haven't found original source yet
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 ..."
https://www.energy.gov/fecm/transformative-power-systems
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
Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2014
https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks-1990-2014
2016 Complete Report (PDF)
Using data from 2014
Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2014
https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks-1990-2014
2016 Complete Report (PDF)
Datapoint was found on page 115, from pie chart and line graph, using data from 2014
https://www.eia.gov/environment/emissions/co2_vol_mass.php
https://www.api.org/news-policy-and-issues/blog/2022/05/26/top-numbers-driving-americas-gasoline-demand
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
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
For a gasoline car (typical usage): (calculation loading)
For an EV charged by coal power plants (same amount of driving as above):
(calculation loading)
For an EV charged by natural gas power plants (same amount of driving):
(calculation loading)
For an EV charged by advanced (combined-cycle type) natural gas power plants (same amount of driving):
(calculation loading)
Battery production emissions
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, let's assume that batteries account for the entire difference between electric cars and gasoline cars, in terms of GHG emissions of production divided by vehicle lifespan.
https://ev-database.org/cheatsheet/useable-battery-capacity-electric-car
What is the environmental impact of lithium batteries? - Changeit ...
changeit.app › blog › 2021-03-26-environmental-impact-of-lithium-batteries
For battery production: (calculation loading)
Now, for the final comparison: (calculation loading)
(calculation loading)
(calculation loading)
Thus, with coal power, emissions are worse than driving a gasoline-powered car. But for advanced natural gas power plants, emissions are about half. In either case, 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.