We use an integrated suite of sector-specific models for buildings, transportation, energy, and waste (Figure 1). The goal of each model is to assess the impact of a particular policy on the emission of GHGs. This is accomplished in a series of steps. First, data are assembled that characterize (i) key drivers (population, building stock, demand for travel, energy use, etc.), and (ii) possible policies (building codes, parking fees, waste reduction mandates, etc). Second, each sector model employs specific techniques to evaluate the effect of a policy or technology choice on energy use and emissions in that sector. Third, the forms of energy are determined by the supply modes for each sector (electricity grid, gas delivery, etc.). An integrating model pulls all this together and generates results that include emissions of greenhouse gases and other air pollutants, health impacts, and the potential impacts of GHG mitigation on socially vulnerable populations.
The heart of our approach is a system to manage very disparate types of data (Figure 2). The “City Data System” converts all the data into a common form that can be used by the sector models. This approach enables the fullest use of data in the models, as well as the visualization of data and results in a variety of forms (charts, infographics, maps, etc.)