ROLES OF VARIABLE RENEWABLES IN DECARBONIZED ENERGY SYSTEM: LONG-TERM ANALYSIS UTILIZING A TECHNOLOGY MIX MODEL

Abstract

This study investigates an optimal deployment of variable renewables (VRs) in massive decarbonization in Japan’s energy system toward 2050 under several carbon-dioxide (CO2) mitigation scenarios. A multi-region bottom-up technology mix model which incorporates a high-temporal-resolution power sector is developed and utilized. The model is formulated as a large-scale linear programming model with 14 million endogenous variables and 30 million constraints. Simulation results reveal that severer requirement for CO2 reduction promotes decarbonization in the power sector and electrification at final demand sectors as well as energy conservation. The deployment of VRs increases as the carbon constraint gets rigorous and the large amount of VRs accompanies huge installation of batteries while suppressed electricity also increases due to intra-regional imbalance in demand and supply, and capacity limitations of inter-regional transmission lines.