Grid operation and investment limitations for variable renewable energy in integrated assessment modelling

Abstract

In order to integrate more and more variable renewable energy sources (VRES) electric grids play a significant role. There is an obvious need for more interconnections and more enhanced grids with more VRES. On the other side, the monetary, material, social and spatial constraints (free corridors) impose limits on grid expansions. Robust modelling of electric grids (distribution, transmission and interconnection) at World level in integrated assessment models (IAMs) is beyond the state of the art of current computation capabilities and data availability. A number of relevant input data like length of the grids, voltage levels, rated power, and after that material prices, population density, VRES shares of generation and flexibility technologies, hourly curtailments in the energy system are not sufficient to calculate explicit limitations imposed by power flows. Therefore, the idea of this paper is that in the absence of sufficient data and computability, for the first time some expert assumptions in the form of proportions are used to represent interconnection grids as an important constraint and flexibility option for variable renewable energy production, modelled at hourly level during one year using EnergyPLAN. These assumptions are about proportions of newly integrated renewable energy between transmission and distribution grids, proportions of grids to the generation plants and their utilization. Suggested method for application in WILIAM will be illustrated.