Fleet EV Charger Demand Optimisation

Fleet Charger Optimisation Algorithm Progress

EVisi are please to display some of the results of the our fleet charger site demand optimisation projection supported by the NZ Low Emmision Vehicles Fund and in partnership with University of Auckland Engineering school.

Our goal is to develop a fast acting practical algorithm to optimise EV fleet charger output power (kW) profiles to minimise the overall site electricity demand profile while still ensuring that connected electric vehicles are charged to desired battery state of charge at required time.

An example of a optimising the output of 10 chargers with 20 connected vehicles (2 vehicles per charger) to minimise the overall charger power demand profile is shown in the image below.

Why would we do this ?

Its a good question 🙂

As electric vehicles require charging from the electricity network, especially many chargers using a single site electricity transformer for a office or apartment building or a commercial site, we will need to ensure that we efficiently charge vehicles without overloading the local network delivery capacity.

With some many vehicles and charging variables, we cant expect people to make decisions to continuously to manage this task so we need to develop software tools to automate this process.

EVisi has started the process of developing and testing optimisation algorithms to automate this task.  The EVisi system communicates with EV chargers and enables data to be collected for the attached vehicles such as battery capacity (kWhr), initial and desired battery state of charge, charge completion time etc.  The EVisi system also estimates the maximum power available to all the chargers at a particular site to ensure that each charger is optimised to not exceed the total maximum available power that the site transformer can deliver.

We also include market or retailer pricing schedules into decision making to deliver lowest cost charger operation.

A comparison between a non optimised and optimised fleet charging forecast schedule is shown below.  We hope this can help explain the requirement for charger power management, especially as more electric vehicles are used on New Zealand roads.