Hybrid and Plug-In Electric Vehicle Emissions Data Sources and Assumptions
The following sources and assumptions were used to calculate the emissions, fuel use, and electricity sources for conventional and electric-drive vehicles on the hybrid and plug-in electric vehicle emissions page.
Electricity Sources and Annual Vehicle Emissions
The following sources and assumptions were used to show electricity sources and calculate the annual vehicle emissions for a conventional, hybrid electric, plug-in hybrid electric, or all-electric vehicle.
| Parameter | Value | Source |
|---|---|---|
| Pounds of CO2e per gallon of gasoline | 23.5 | Full fuel cycle (well to wheels) greenhouse gas emissions (GHG) factors derived from GREET 2015. Results in CO2 equivalents (model available at http://greet.es.anl.gov) |
| National average electricity GHG/kWh | 1.18 | Energy Information Administration, Electricity Net Generation, Open Data, API http://www.eia.gov/opendata/qb.cfm?category=1 |
| Electricity fuel mix | varies | Energy Information Administration, Electricity Net Generation, Open Data, API http://www.eia.gov/opendata/qb.cfm?category=1 |
| Conventional vehicle mpg | 24.3 | CAFÉ Standard |
| HEV mpg | 44.4 | Sales weighted average of 2016 model year vehicles with sales in 2015: 2015 sales from "U.S. HEV Sales by Model" (https://www.afdc.energy.gov/data/vehicles.html); MPGs from 2016 Fuel Economy Guide (https://www.fueleconomy.gov/feg/) |
| PHEV mpg | 37.9 | Sales weighted average of 2016 model year vehicles with sales in 2015: 2015 sales from "U.S. Plug-in Electric Vehicle Sales by Model" (https://www.afdc.energy.gov/data/vehicles.html); MPGs from 2016 Fuel Economy Guide (https://www.fueleconomy.gov/feg/) |
| PHEV kWh/mi | 0.367 | Sales weighted average of 2016 model year vehicles with sales in 2015: 2015 sales from "U.S. Plug-in Electric Vehicle Sales by Model" (https://www.afdc.energy.gov/data/vehicles.html); MPGs from 2016 Fuel Economy Guide (https://www.fueleconomy.gov/feg/) |
| PHEV all electric range | 33 | Sales weighted average of 2016 model year vehicles with sales in 2015: 2015 sales from "U.S. Plug-in Electric Vehicle Sales by Model" (https://www.afdc.energy.gov/data/vehicles.html); MPGs from 2016 Fuel Economy Guide (https://www.fueleconomy.gov/feg/) |
| EV kWh/mi | 0.32 | Sales weighted average of 2016 model year vehicles with sales in 2015: 2015 sales from "U.S. Plug-in Electric Vehicle Sales by Model" (https://www.afdc.energy.gov/data/vehicles.html); MPGs from 2016 Fuel Economy Guide (https://www.fueleconomy.gov/feg/) |
| Percentage of PHEV annual miles driven on electricity | 55% | Estimate based on the current industry standard, SAE J2841 (available in http://avt.inel.gov/pdf/EVProj/EVProjectUtilityFactorVolt.pdf), assuming the PHEV all-electric range is 33 miles. |
| Average annual vehicle mileage (miles) | 11,824 | Transportation Energy Data Book #34 (http://cta.ornl.gov/data/download34.shtml), Table 8.1; Total vehicle miles traveled divided by vehicles in operation, 2013 |