California E-Bus to Grid Integration Project
Antelope Valley Transit Authority (AVTA) has pledged the most aggressive commitment to zero emissions transit in North America—100% of their 80-bus fleet.
The team developed an E-Fleet Energy Model that accounts for the effects of weather, geography, drivers' skill and other factors on the kWh/mi. efficiency of the E-Buses. Fleet operators are seeing the benefits of driver training in reducing the fleet's overall energy usage. The team also determined the greatest energy cost savings can be achieved through managed charging to reduce peak loads and charge during lower time-of-use rates. The project team worked with transit industry leaders in knowledge transfer activities to disseminate transit fleet electrification best practices.
This project focused on improving the economics of incorporating e-buses in a transit agency fleet. The project team worked with the Antelope Valley Transit Authority (AVTA) to evaluate multiple scenarios, including smart charging, improving vehicular energy efficiency through best driving practices, and using the vehicle batteries for grid services when the E-buses are not being used for their routes. More effective smart charging reduces the frequency and duration of in-route charging, and the fuel economy improvements that come from smart driving result in operational cost savings. By reducing the likelihood that several/all E-buses will be charging at once, smart charging can achieve greater flexibility and decrease demand charges.
By training operators on best practices and giving them customized feedback on how to continuously improve their driving habits, energy consumption per mile has improved substantially.
Data-driven models have shown that managed charging will be able to minimize operating costs for a fleet operator while also accommodating the need for grid reliability.