En-ROADS is a System Dynamics model. It was built in the Vensim modeling software and transformed into an online simulation via the SD Everywhere converter built by Climate Interactive and Todd Fincannon. En-ROADS is an extension of (and contains most of) the C-ROADS simulator, which focuses on international emission dynamics.

The model is an ordinary differential equation system, solved by Euler integration. No intertemporal or short-term equilibrium is assumed. In other words, En-ROADS is not an equilibrium model where technology development is driven by cost-optimal supply-demand balance. Instead, decisions about energy sources and intensities in the model are represented by simple heuristics with myopic expectations.

The model represents key processes in the energy system and its connections to climate, economy, and environment for a single, global region. Distinctions among regions are obviously important in the real world. However, this would considerably complicate the simple accounting framework of the model, particularly by introducing trade issues, rendering it less useful for rapid scenario experimentation. En-ROADS is calibrated to a suite of Integrated Assessment Models (IAMs). You can learn more about the structure, equations, data sources, calibration, and testing of En-ROADS in the Reference Guide.

The En-ROADS simulator is intended for interactive scenario exploration. It helps users to think about:

  • Dynamics of capital stock turnover

  • Growth, energy intensity, and carbon intensity (elements of the Kaya identity) as drivers of emissions

  • Implications of technological lock-in for particular technologies

  • Effective combinations of supply-side vs. demand-side, or technology-driven vs. incentive-driven, policies, as well as their side effects

  • The scale of socioeconomic and emissions changes required to meet climate goals