To Represent Electric Vehicles in Electricity Systems Modelling—Aggregated Vehicle Representation vs. Individual Driving Profiles

Maria Taljegard,Filip Johnsson,Mikael Odenberger,Lisa Göransson

doi:10.3390/en14030539

Abstract

This study describes, applies, and compares three different approaches to integrate electric vehicles (EVs) in a cost-minimising electricity system investment model and a dispatch model. The approaches include both an aggregated vehicle representation and individual driving profiles of passenger EVs. The driving patterns of 426 randomly selected vehicles in Sweden were recorded between 30 and 73 days each and used as input to the electricity system model for the individual driving profiles. The main conclusion is that an aggregated vehicle representation gives similar results as when including individual driving profiles for most scenarios modelled. However, this study also concludes that it is important to represent the heterogeneity of individual driving profiles in electricity system optimisation models when: (i) charging infrastructure is limited to only the home location in regions with a high share of solar and wind power in the electricity system, and (ii) when addressing special research issues such as impact of vehicle-to-grid (V2G) on battery health status. An aggregated vehicle representation will, if the charging infrastructure is limited to only home location, over-estimate the V2G potential resulting in a higher share (up to 10 percentage points) of variable renewable electricity generation and an under-estimation of investments in both short- and long-term storage technologies.

Highlights

The results presented are from a model run with yearly driving profiles (YDP), 30 kWh and median (Median) yearly driving distances
The results presented are from a model run with YDP, 30 kWh battery battery capacity, with V2G and connected to the grid at all parking longer than 1 h
One of the approaches was to use an aggregated vehicle representation, while two of the approaches include individual driving profiles (i.e., 200 representative daily driving profiles and 426 ~2-month driving profiles extrapolated to full-year driving profiles)

Summary

Introduction

Union framework [2,3] will most likely require large-scale employment of electric vehicles (EVs) over the coming decades. New EVs will entail a new electricity demand and charging infrastructure that must be integrated into the electricity supply system. If the integration of EVs comes with an appropriate strategy, the new EV demand could offer benefits in terms of flexibility of the load, e.g., demand response services and, possibly, discharge back to the grid (i.e., vehicle-to-grid; V2G). It is essential to investigate EV’s impact on the current and future electricity system. This can be accomplished by, for example, using electricity system optimisation models [4,5,6]

Results

Discussion

Conclusion