Use of electric vehicles as a quick response energy storage : case study for Sri Lanka

Abstract

With the fossil fuels depleting, the non-conventional energy sources is taking the wheel I the field of electricity generation. Yet, their inconsistencies owing to reliance on intermittent energy sources such as wind and solar necessitate means of catering the dips in generation. V2G systems become instrumental is levelling out the load curve, facilitating charging of plugin vehicles during over generation and discharging at times of lack of generation. The study was done to analyse the practicability of implementing plugin vehicle based energy storage in Sri Lanka. A survey was done to identify the plugin electric demographic that included plugin patterns, distance driven, length of ownership and the willingness to remain in EV segment, traction battery degradation and overall attitude towards partaking in a V2G scheme. Main challenge is quantifying the battery degradation with extensive usage as a V2G source. In contrast, using EV batteries as quick response, low duration, low energy power source, it was understood that enormous financial and economic benefits can be yield merely by minimising un-served energy following load shedding caused by frequency violation events. With low count of average daily frequency violations battery discharge becomes minimal, alleviating the adverse effect on the vehicle range with remaining charge and cyclic ageing. Considering the cost benefit obtained from preventing load shedding versus the costs incurred by EV owners, using EVs as a fast response, low duration energy storage that can cater system emergencies is profitable in utility perspective.