Top-down and bottom-up policy evaluation – a multi-model approach

Panel: 8. Monitoring and evaluation: building confidence and enhancing practices

This is a peer-reviewed paper.

Authors:
Eamonn Mulholland, University College Cork, Ireland
Fionn Rogan, University College Cork, Ireland
Eamonn Mulholland, University College Cork, Ireland
Brian Ó Gallachoir, University College Cork, Ireland

Abstract

This paper describes a multi-model approach to evaluating energy efficiency policies and uses it to assess energy efficiency options in car transport. The methodology comprises a soft-linking mechanism between two bottom-up techno-economic modelling tools, i) a full energy systems optimisation model and ii) a car stock simulation model. The energy systems model is used to inform energy efficiency targets for car transport over the period to 2050, using top-down policy evaluation, informing in essence a technology roadmap for car transport. This is done by providing energy system pathways to meet future energy needs at least cost and constrained by a maximum level of CO2 emissions. The simulation model then assesses this technology roadmap using higher temporal (annual) resolution, increased detail on individual car technologies and by adding a bottom-up assessment of policy measures. Through use of additional detail, the simulation model is able to use scenario analysis to evaluate particular aspects of the implementation of a policy, such as varying implementation rates and the interaction effect, and can provide insight into which policies are effective. The purpose of this paper is to illustrate how this multi-model approach can be used to generate technology roadmaps (to inform targets) and add value to this by also exploring policy roadmaps to deliver the technology goals. The paper applies this methodology to a single Member State, Ireland.