Cascadia modeling shows policy shifts reshape Mountain View's path to earlier carbon goals

Consultants contracted by the city presented a three‑scenario greenhouse‑gas forecast on June 26 that shows Mountain View’s ability to achieve accelerated carbon‑neutral targets (2035 or 2040) depends heavily on state and federal actions — and on the fate of vehicle‑emissions rules.

Cascadia Consulting told the Council Sustainability Committee that a “business as usual” scenario, which assumes no additional policies, would increase Mountain View’s community emissions well above the city’s 2022 baseline as population and employment grow. Under an “adjusted business as usual” scenario that includes expected federal, state and regional measures and current electric‑vehicle market trends, the city would still face higher emissions in 2035 and 2040 than in 2022, with reductions only materializing by 2045 in the model used.

Haley Weinberg of Cascadia summarized the model’s near‑term results: “Emissions are expected to increase by 60% by 2035, 81% by 2040, and 103% by 2045,” compared with Mountain View’s 2022 community inventory in the unmitigated scenario. The consultants emphasized that those numbers change substantially when California’s vehicle‑emissions policy — often called Clean Cars II in the briefing — is included. The ability of California to implement its vehicle standard was described at the meeting as undercut when federal waivers were revoked; Cascadia noted the revocation materially reduces the modelled emissions benefits from transportation regulations.

The analysis incorporated several specific adopted policies and market trends: SB 100 (California’s renewable-portfolio standard), the California Green Building Standards Code (energy-efficiency improvements for new construction), Bay Area Air District rules on replacement of gas furnaces and water heaters, the Low Carbon Fuel Standard and existing EV market trends. Cascadia also modeled the statewide short‑lived climate pollutant rule (SB 1383) for waste reductions. The consultants said on‑road vehicles represented 63% of Mountain View’s 2022 inventory and therefore dominate the emissions gap when vehicle standards are weaker.

Cascadia presented two adjusted scenarios: one that included California’s zero‑emission vehicle sales measures and one that excluded them after the federal waiver revocation. Without the Clean Cars rule in force, the consultants reported Mountain View would be responsible for reducing roughly 44% of its 2045 business‑as‑usual emissions by local action; with the rule in place, the modeled local share was far smaller. The consultants cautioned the metrics are sensitive to policy assumptions and that market trends (consumer EV adoption) were included to reflect continuing electrification even amid regulatory uncertainty.

Rebecca Lucky, the city’s sustainability manager, told the committee the project’s next phase will model up to 10 local decarbonization actions this summer — items that could form a five‑year strategy to reduce the remaining emissions gap. Potential local measures that staff flagged included reach codes (discussed elsewhere in the meeting), time‑of‑sale electrification mechanisms, outreach and education, transportation‑demand measures, EV charging at multifamily properties, incentives for e‑bikes and shared micro‑mobility, and electric community shuttles. Staff said they will return with modeled impacts and a recommended prioritization later this year.

Ending: Staff said they will refine the memo to reflect rapidly changing state and federal policy developments, incorporate Cascadia’s local‑action modeling this summer, and return to the committee with detailed recommendations by late 2025 for consideration in the city’s climate work plan.