Introduction

Bottom-up models provide the technology details for modelling the long-term pathways. These models have rich information on technology types and their characteristics. Usually, these are based on linear optimization framework. It is important to use such models while determining the feasibility of deep decarbonization scenarios because they capture the technology explicitness that is not captured by the top-down models that focus more on macroeconomic context.

This chapter provides details on setting up these kinds of models through the case of the Asia–Pacific Integrated Model (AIM), which is a collection of computer simulation models used to evaluate policy alternatives for sustainable development in the Asia–Pacific area. Within this collection, AIM/Enduse is a model for technology selection that is used to analyse national plans for reducing GHG emissions and reducing local air pollution. An analysis of energy policy can benefit from it as well.

AIM/Enduse model replicates energy and material flows in an economy, from basic energy and material supply through secondary energy and material conversion and supply to end-use service satisfaction. AIM/Enduse simulates these energy and material fluxes using precise representations of technology. It began as a tool for evaluating policy options for mitigating climate change and its consequences, but it has since expanded its scope to include analysis of other environmental issues such as controlling air pollution, managing water resource flows, controlling land use, and growing environmental field.

There are more than 20 models that have been built thus far, and they can be divided into emission-focused models, climate change models, and impact assessment models that provide implications for climate policy.