Fast-Charging Network Key to Increasing Electric Vehicle Use

Posted on: 31 March 2016

Analysis of the charging patterns of existing electric vehicle users has provided key insights for policymakers in the strategic development of charging infrastructure in Ireland.

While the grid is currently able to supply demand, new research from engineers at the Centre for Transport Research in Trinity College Dublin suggests policymakers across the island of Ireland will need to adapt the existing charging infrastructure to support electric vehicle buyers attracted by low running costs and associated environmental benefits.

Electric vehicles (EVs) are emerging to prominence in many countries around the world, including in Ireland where there has been a 115% (253 additional vehicles) increase in electric vehicle adoption in 2015.

To satisfactorily cater for the varying charging needs of users, a comprehensive charging network is required, similar to existing fueling stations for conventional vehicles, in addition to chargers located in homes.

Professor of Civil Engineering at Trinity, Margaret O’Mahony, led the research, which was recently published in the leading journal Energy Policy.

Professor O’Mahony said: “Ireland has an extensive charging infrastructure but its development into the future will be key to electric vehicle adoption.”

“The best way to inform future installations and – where necessary – modify existing charging behaviour is to monitor the way infrastructure is used and learn from that.  We had the unique opportunity to analyse usage statistics for all types of public and private electric vehicle charging infrastructure for an entire country.”

The Trinity team conducted a detailed analysis of how existing electric vehicle users charge their vehicles to answer the following questions: How popular are public charge points compared to home charging? If electric vehicles become as popular in Ireland as they have in Norway, what impacts will that have on the demand for electricity, and how would it be managed? Can the strategic location of public charge points provide the infrastructure needed by electric vehicle users?

The team extracted key findings from over 40,000 charging events from over 700 chargers, which were installed by the ESB eCar Ireland project across the country.

Dr Peter Weldon, who worked on the project, said: “The analysis of existing user charging data revealed that electric vehicle owners prefer to charge at home in the evening after returning from work, which coincides with the time of overall peak electricity demand on the electrical grid.”

“While this does not pose an immediate problem to the electrical grid since the grid has sufficient generation capacity to cater for the current charging demands of electric vehicle users, a large increase in the market penetration of electric vehicles may cause concern if all charging demands continue to occur during the evening peak period; as such monetary incentivisation and smart metering will be necessary to shift the electric vehicle charging demands to the night-time period of low overall electricity demand.”

It became clear during the analysis that the fast-charging infrastructure was used in a very specific manner. As expected, at fueling stations, both standard and fast chargers were being used for short periods so that drivers could ‘top-up’ using a standard charger or to obtain a large boost of energy from a fast charger depending on the length of their next trip.

In car parks (including park & ride) it would have been expected that fast chargers would have both lower duration and higher consumption charge events but it was found that the consumptions were similar for both types of chargers.

Dr Patrick Morrissey, who also worked on the project, said: “The usage patterns suggest that users charge their batteries to increase their local range in urban and suburban environments, while in more rural settings they used fast chargers to undertake longer trips. In both instances it was clear that the fast-charging infrastructure is favoured by users with usage statistics approaching the lower range of what would be deemed commercially viable in some locations.”

“Were this trend to continue with increased EV market penetration, the demand for fast charging would lead to the viability of the network. Given this apparently favourable attitude to fast chargers by EV users, concentrating on the rollout of this form of infrastructure may be one way to encourage the switch to EVs among motorists.”

The results of the research were published in Energy Policy and can be viewed here.

Media Coverage


Media Contact:

Thomas Deane, Media Relations Officer | | +353 1 896 4685