How school buses are powering the grid

Last summer, bus manufacturer Zum announced the launch of a virtual power plant made up of the largest electric school bus fleet in the country. Together with the Oakland Unified School District in California and Pacific Gas & Electric, Zum worked to integrate the buses into the local grid.

With their short, predictable routes and ability to send power to the grid during peak demand periods, electric school buses make perfect sense for vehicle-grid integration. Rudi Halbright, PG&E’s expert product manager of vehicle-grid integration, says the challenge is teaching customers how to rethink their relationship with vehicles and power bills.

“Not only are we introducing people to a new way of using vehicles to provide energy and having them think differently about their vehicles, we’re also introducing this idea of hourly flexible pricing,” Halbright said on the With Great Power podcast. That concept, he added, “is new to most customers, is a little anxiety producing to many,” and also “adds complexity.”

Still, he says the Zum project is a key early milestone for the utility as it works toward its goal to power three million EVs by 2030 — with two million of those serving as flexible load through vehicle-grid integration applications.

Navigating evolving standards

For the Zum project, Halbright orchestrated the installation of bidirectional chargers to support 74 electric school buses at a depot in Oakland, as well as grid-following inverters to bring the battery’s direct current to alternating current and sync up at the same frequency. “So as the grid fluctuates, they can match it and meet it where it is,” he said.

But still-evolving standards for smart inverters, as well as pandemic-related supply chain delays, stymied the project. The partners ultimately ironed out those problems in time for the 2024-2025 school year — but Halbright said he is still concerned that standards development is slowing vehicle-grid projects more broadly.

”While we’re fortunate that the TELUS charger that Zum is using has received certification now, some of the equipment we might otherwise be using on other projects has not gotten that certification yet,” he said. “Certification can take anywhere from months to years. So that’s been a big challenge.”

Hardware isn’t the only challenge

By participating in California’s  Emergency Load Response Program, Zum was able to earn up to $2 per kilowatt-hour of energy that its buses sent to the grid during periods of high demand. And because Zum can export up to two and a half megawatts of energy, “we’re talking [about] quite a significant contribution to their bottom line,” Halbright said.

But outside of that incentive, determining pricing models for fleet owners has been tough. “We’re early in our ability to accurately communicate how much of an earnings opportunity there is for customers,” he said.

V2G participants already reckoning with the costs and complexity of electrification want clarity on that opportunity.  Customers can make money or significantly lower their energy bills with an electric fleet, but timing is critical.

“Because once they’ve already done their trenching, installed unidirectional chargers, it’s really less likely to be worth it for them to do it over again,” Halbright said. That said, he’s hopeful that the benefits of the program will soon become clear to all.

”I keep focused on the goals, what we’re trying to achieve, and [keep] committed that we’re going to go there,” he said. “We’re depending on this to make a big impact.”

For the full conversation with Rudi Halbright, listen to his interview on season 4 of With Great Power here.

With Great Power is a show about the people building the future grid, today. It’s a co-production of GridX and Latitude Studios. Subscribe on Apple, Spotify, or anywhere you get your shows.

Read the original article from Latitude Media here.