California Freight Cleanup → Element 1
What does freight emissions actually look like through 2030?
Three transport paths and four building paths, run against a 32-million-resident California grid with 10,000 Monte Carlo draws and full disadvantaged-community equity tracking. The bottom line: ACC II compliance alone avoids about 13 deaths per year at zero added cost. The $2 B accelerated push avoids 87. But the baseline is still the optimal choice in 55.8% of uncertainty draws — the case for accelerating isn’t a slam dunk.
How we got there
We treat the 2020–2030 emission trajectory as a set of policy-indexed scenarios — not a static table. Five transport scenarios bracket the realistic CARB ACC II decision space (T1–T5), and four building electrification scenarios (B1–B4) cover the corresponding residential gas-combustion reductions. Each scenario translates into spatially-varying PM2.5, NO2, and O3 concentration changes using ISRM sector marginals anchored to AQS-validated regional baselines (LA Basin 14 µg/m³, SJV 16, Bay Area 10, Sacramento 9, rest-CA 8). A 10,000-draw Monte Carlo converts those concentration changes to health outcomes and dollar benefits under full dose-response and value-of-life uncertainty. The third investigation crosses all transport and building scenarios — 20 combinations — to check whether the health gains from both sectors add up or interact. They add up: residuals below 0.3 deaths per scenario.
What we found
ACC II compliance (T1) avoids ~13 deaths per year by 2035 at zero direct program cost
The mandated ZEV trajectory (35% new sales by 2026, 100% by 2035) avoids approximately 13 deaths per year by 2035 against a frozen-2011 baseline (the year-2035 incremental health benefit), at zero incremental program spending. Decomposed at the gross-flow level: 103.1 PM2.5 deaths avoided are partially offset by 51.9 ozone deaths caused (50.4% offset), yielding a 63.8 deaths/yr gross-flow figure that includes legacy-fleet phaseout effects on top of the marginal ACC II benefit; the —13 figure isolates the marginal ACC II compliance effect against frozen-2011. Both numbers are pre-Sillman; see caveat below on the ozone code path.
The $2B accelerated scenario (T2) delivers the largest raw PM2.5 benefit, but T1 dominates on net-benefit
T2 (ACC II targets three years early via $2B incentives) avoids 87.0 deaths per year by 2035 against the frozen baseline, with a higher ozone offset (52.9%). VOI analysis places T1 as optimal in 55.8% of the 10,000 uncertainty draws; T3 (delayed, no ACC II waiver) wins in 30.5% of draws. The $125M EVPI signals meaningful residual uncertainty about which transport policy is truly optimal.
Building electrification contributes a real but small increment: ~37–82 deaths avoided, with a 15–17% ozone offset
Under current-policy enforcement (B1), the building sector avoids 37 deaths per year by 2035 at no program cost; the aggressive $2B retrofit program (B2) avoids 82. The ozone offset is smaller than for transport (15.5–15.7%) because residential NOx is dispersed rather than concentrated on arterials. B1 is optimal in 98.9% of MC draws; the $5.5M EVPI suggests further research investment before deciding between B1 and B2 is not warranted.
Crossing the two sectors confirms additivity: combining T1+B1 at zero cost yields 50.2 deaths avoided with no cross-sector interference
Investigation 7 crosses all transport and building scenarios (20 combinations) and finds that combined benefits match the sum of sector-specific benefits to within 0.3 deaths (<0.06%). At a $1.0B envelope the equity-prioritized combination T4+B1 yields 85.3 deaths avoided and the highest DAC share (20.7%). The additivity result is a property of the linear concentration model; Investigation 4-2 probes nonlinear ozone chemistry separately.
Aggressive heavy-duty NOx controls (T5) are uniquely risky: the ozone offset reaches 93% at 2035
T5 pairs LDV compliance with aggressive HDV NOx reduction. By 2035, PM2.5 benefits are no larger than T1 (103.1 deaths avoided) but O3 harm rises to 95.6 deaths caused in 6,216 net-negative cells covering 12.2 million residents. The net benefit shrinks to 39.8 deaths avoided — less than T1. This is the strongest quantitative argument against leading with NOx-only controls absent coordinated VOC management.
Investigations
Transport Electrification
Five transport scenarios (T1–T5, ACC II compliance through heavy-duty NOx) against a frozen-2011 baseline; 10,000-draw MC at four target years; Sobol sensitivity and VOI.
Building Electrification
Four building scenarios (B1–B4, current enforcement through $2B aggressive retrofit); residential gas-combustion emission reductions at 21,164 grid cells; cooking-first urban equity variant.
Combined Electrification
20 cross-sector portfolios (4T × 4B); joint MC, net-benefit ranking, sector decomposition, and additivity test.
How it connects to the rest of the cascade
The transport, building, and combined investigations are foundational — they draw only from public data sources (CARB AQMP 2022, EMFAC 2025, ISRM sector marginals, AQS regional means, 2022 ACS demographics) and feed their outputs forward into two other elements:
- Element 4 (co-benefits / disbenefits): Inv 11 (CRF-conditional policy) and Investigation 4-3 (wildfire vs. electrification) load the Investigation 1-1 and 6 MC draw arrays and ozone-disbenefit JSON files directly to re-weight benefits under alternative CRF posteriors and to compare the transport ozone offset against wildfire-smoke chemistry.
- Element 6 (ratepayer burden / portfolio net benefit): Investigation M-1 (portfolio frontier) bulk-loads all scenario MC results from Investigation 1-1 and 6 to plot the cost-effectiveness frontier across the full the cascade intervention menu. T1+B1 anchors the zero-cost floor; T4+B1 anchors the $1B equity frontier.