Commissioners press county on electric bus costs and service tradeoffs after pilot suggests 1:1 replacement

Arlington transportation staff told the commission that pilot operations of four battery‑electric buses (BEBs) suggest the county can replace diesel or compressed‑gas buses at a 1:1 ratio, but commissioners pressed staff on cost differentials and service consequences.

"Based on the pilot of the four battery electric buses that we have in our inventory we determined that we are able to replace our [current] buses at a 1:1 ratio," Sarah Crawford said, describing six months of route testing, winter performance and hilly‑terrain data that informed the decision. "We feel comfortable with the one to replacement ratio based on the routes that we've run."

Several commissioners asked whether the higher unit cost for BEBs forces a smaller fleet and therefore reduced frequency. Crawford said anecdotal contract pricing shows a cost differential that has driven earlier replacement ratios: "The 1.4 you saw in the presentation is based on current contracts. I believe it's $800,000 for a CG, the $600,000 differential," she said.

Why it matters: commissioners expressed concern that spending more per bus could reduce the total number of vehicles and undermine service frequency improvements that encourage mode shift. Vice Chair Ferman and others argued that increasing bus frequency — even with less advanced vehicles — can do more to reduce single‑occupant vehicle use than buying fewer, pricier BEBs.

Staff acknowledged procurement constraints (limited suppliers and longer lead times), capital costs that may change, and an evolving industry on battery longevity and replacement timing. Crawford said the CIP currently includes about $68 million for the BEB transition and associated facility upgrades but that numbers will be revisited as more data arrive.

Next steps: commissioners asked staff to make underlying pilot analysis and any cost‑benefit work available; Crawford said the full pilot study will be published later in the year.