When are fossil fuels displaced? An exploratory inquiry into the role of nuclear electricity production in the displacement of fossil fuels.

We explore how renewable electricity production influences nuclear energy and fossil fuel use in the electricity sector for 109 nations from 1960-2015 and how such patterns change over time. We find that although a one-unit increase in the number of kWh produced from renewable sources does not appear to displace an equivalent number of kWh from fossil fuels, such an increase is associated with an equivalent reduction in the number of kWh drawn from nuclear sources between 1960 and 2015. However, further analyses indicate that there has been a trend toward displacement of fossil fuel sources by renewables, as well as an attenuation of the displacement of nuclear sources by renewables, since the late 1990s in nations with the capacity for nuclear electricity production. These findings suggest that social, political, and economic processes may prevent renewables from being deployed such that they decarbonize the existing electricity grid, especially outside of the 31 nations capable of producing electricity from nuclear energy sources.

How do slums change the relationship between urbanization and the carbon intensity of well-being?

This study examines how the relationship between urbanization (measured as the percentage of total population living in urban areas) and the carbon intensity of well-being (CIWB) (measured as a ratio of carbon dioxide emissions and life expectancy) in most nations from 1960-2013 varies based on the economic context and whereabouts of a substantial portion of a nation's urban population. To accomplish this, we use the United Nations' (UN) definition of slum households to identify developing countries that have substantial slum populations, and estimate a Prais-Winsten regression model with panel-corrected standard errors (PCSE), allowing for disturbances that are heteroskedastic and contemporaneously correlated across panels. Our findings indicate that the rate of increase in CIWB for countries without substantial slum populations begins to slow down at higher levels of urbanization, however, the association between urbanization and CIWB is much smaller in countries with substantial slum populations. Overall, while urbanization is associated with increases in CIWB, the relationship between urban development and CIWB is vastly different in developed nations without slums than in under-developed nations with slums.