1166247 - Analysis of Changes to Environmental Justice-Related Air Pollutant Concentration and Public Health from 100% Renewable Electricity Pathways for the City of Los Angeles (LA100)

The Los Angeles 100% Renewable Energy Study is a pathbreaking effort to model a transition to a clean energy and mobility future for the City of Los Angeles (LA). Environmental justice (EJ) was both a key motivation for the study and an intended outcome for the transition to 100% renewable electricity for the Department of Water and Power. By evaluating model outcomes inside and outside disadvantaged communities (DAC) in LA (based on present-day CalEnviroScreen scores in LA), we develop a first estimate of how benefits from each LA100 scenario might be distributed, including changes to ambient air pollutant concentrations (fine particulate matter and ozone) and air-quality-related health impacts (emergency room visits from asthma, cardiovascular-related hospital admissions, and premature mortality). Air quality modeling was achieved through WRF-Chem and health benefits analysis through BenMAP.
In the 2012 Baseline, census tracts designated as DAC have, on average, higher mean concentration of PM2.5 but lower mean concentration of summertime ozone compared to non-DAC tracts. In all evaluated LA100 scenarios (year 2045), the relative patterns of pollutant concentration experienced by DAC and non-DAC tracts persists; that is, all future scenarios show higher concentrations of PM2.5 and lower concentrations of ozone in DAC tracts compared to non-DAC tracts. Relative to the Baseline, annual-average, population-weighted concentration of PM2.5 decreases by about 0.39–0.56 µg/m3 (3.3%–5.2%) in all LA100 scenarios in 2045 on average throughout LA. PM2.5 concentration reduction is similar for DAC census tracts as compared to non-DAC tracts for the evaluated LA100 scenarios. By contrast, population-weighted, summertime ozone increases by a total of about 4.2–5.3 parts per billion (ppb) (10%–13%) in all evaluated LA100 scenarios relative to the Baseline. Projected ozone concentration in 2045 for DAC tracts increases slightly more compared to that for non-DAC tracts.
On balance, net air pollution-related health effects decrease citywide under LA100 scenarios compared to the Baseline, including both DAC and non-DAC census tracts alike. Yet within the citywide benefits, all comparisons among future LA100 scenarios evaluated in the year 2045 yield greater change in health endpoints for DACs as compared to non-DACs for all four endpoints investigated. The differences between DAC and non-DAC are not large or statistically significant in many cases. All LA100 scenarios evaluated indicate improvements in two health indicators— premature mortality and cardiovascular disease—compared to the Baseline. However, owing to the aforementioned increase from 2012 in ozone concentration in LA100 scenarios, the number of annual asthma-related emergency room visits increases in both tract categories. Within the context of the how the LA100 scenarios were defined, it appears that investment in electrification of transportation, appliances in residential and commercial buildings, as well as the Ports of Los Angeles and Long Beach provide significantly greater air quality and related public health benefits than does the specific path to 100% renewable energy by LADWP-owned power generation facilities. In summary, all communities will share in the benefits of the LA100 scenarios, but improving EJ outcomes to address historical disadvantages will require intentionally designed processes, policies and programs.