Global biodiversity implications from electric vehicles in the United States

The increasing number of electric vehicles in the United States (U.S.) will alter global agriculture in the upcoming decades because approximately one-third of U.S. maize production is blended with gasoline (Dumortier et al., 2022a). More electric vehicles reduce gasoline demand since every litre of gasoline sold in the U.S. contains approximately 10% ethanol. The reduction in maize ethanol demand leads to lower commodity prices not only for maize but for all other commodities as well because global crop allocation is based on the relative profitability of crops. Previous research has shown that a reduction in total cropland use is expected from an increasing fleet of electric vehicles (Dumortier et al. 2022a,b). This reduction in cropland is leading to fewer biomass and soil carbon emissions from land use change, which can be counted as an additional lifecycle benefit of electric vehicles. This paper is an extension of Dumortier et al. (2022a) by assessing the effects on biodiversity, i.e., richness of mammals, birds, and—if applicable—amphibians. The analysis combines three models: (1) U.S. light-duty vehicle model, (2) global agricultural outlook model, and (3) global biodiversity model. The first two models have been used in previous publications such as Carriquiry et al. (2020) or Elobeid et al. (2021). The biodiversity model is a new addition and is based on data sets presented in Jenkins et al. (2013). The global data set differentiates between mammals, birds, and amphibians and not only covers the species richness, i.e., the number of species for a given area, but also areas with threatened species and with a less than median number of species. We use output provided by Dumortier et al. (2022a) which calculates future U.S. maize ethanol use under various electrification scenarios in the light-duty vehicle sector until 2050. The output is generated by combining the U.S. light-duty vehicle model with the global agricultural outlook model. The important variable for this analysis is the crop area by country/region. Changes in cropland are converted into GIS raster data using the spatial distribution of cropland. Based on overlaying the raster data of changes in crop area with the biodiversity maps, we calculate how many species-rich areas are impacted by an electrification of the U.S. LDV fleet. Since the information is also available for threatened species, the calculations are done for those as well. Preliminary results indicate that fewer species are affected under more rapid electrification. The U.S. has lower species diversity than other important maize exporters such as Brazil. The reduction in the demand for maize leads to an increase in U.S. exports at the expense of other countries that are richer in biodiversity. The increase in U.S. maize ethanol use had important impacts on global agriculture and a more rapid electrification of the U.S. vehicle fleet can have valuable impacts on biomass and soil carbon as shown in previous research but also on biodiversity as shown in this analysis. The analysis adds the component of biodiversity to the discussion around electrification in the United States.