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Studies · CA Air Quality · Investigation 12

What Is the Optimal Policy Portfolio?

No single sector analysis gives the right answer. The portfolio optimization combines transport, building, wildfire, and biomass interventions across all budget levels to find the efficient frontier. The “free lunch” portfolio avoids 1,015 deaths at zero cost. Per dollar, wildfire treatment beats transport electrification ~2.4:1. Building B2 never appears on the frontier until $13.9B.

1,015
Deaths at $0
29
Pareto Portfolios
2.4:1
Wildfire vs Transport ($/death)
4,602
Max Deaths Avoided
Intervention Menu

What’s on the Table

The portfolio optimizer draws from four sectors. Each intervention has a cost and an expected health benefit. The free interventions (T1, B1, retire DTE) form the baseline. Everything else is marginal.

Intervention Deaths Avoided Cost ($B) Sector
T1 Baseline (ACC II) 961 $0 Transport
T2 Accelerated 1,313 $2.0B Transport
T5 Heavy Duty 996 $1.5B Transport
B1 Baseline 50 $0 Building
B2 Accelerated 120 $2.0B Building
Wildfire 5% 724 $0.8–2.5B Wildfire
Wildfire 10% 1,447 $1.7–5.0B Wildfire
Retire DTE Stockton 3 $0 Biomass
CRF Resolution Study $0.002B Information

Deaths avoided use the average of Di and Krewski CRFs (portfolio-level). Transport and building interventions are mutually exclusive within sector (choose one). Wildfire and biomass are additive.

The $2B Question

Where Does the Marginal Dollar Go?

Given the free-lunch baseline, the question is: if you have $2B to spend, where does it do the most good? The answer is unambiguous.

Wildfire ($2B share)
~877
Deaths avoided if $2B is spent on wildfire treatment (~60% of a 10% reduction, which costs ~$3.3B and avoids ~1,447 deaths)
Transport T2 Marginal
367
Marginal deaths above T1 baseline for $2B
Building B2 Marginal
70
Marginal deaths above B1 baseline for $2B

Normalized to the same $2B budget, wildfire treatment avoids ~2.4× more deaths than accelerated transport electrification (~$2.3M/death vs $5.5M/death) and ~12× more than building retrofits. The $2B wildfire figure scales the 10% reduction (~$3.3B, ~1,447 deaths) linearly to the $2B share.

Named Portfolios

Six Policy Packages

A: Free Lunch
1,015
Deaths Avoided
$0
Cost

T1 baseline + B1 baseline + retire DTE Stockton. No new spending required. This should happen regardless of any other decision.

B: Transport $2B
1,382
Deaths Avoided
$2B
Cost

Free lunch + T2 accelerated. The conventional policy choice: spend $2B on faster EV adoption. Adds 367 deaths avoided.

C: Wildfire Instead
1,738
Deaths Avoided
$1.65B
Cost

Free lunch + 5% wildfire reduction. Avoids 724 additional deaths above free-lunch baseline for $1.65B, versus 367 for $2B under Portfolio B. The portfolio optimizer at $2B converges to this exact allocation — wildfire dominates the efficient frontier.

D: All-In $4B
1,452
Deaths Avoided
$4B
Cost

T2 + B2 + retire DTE. Maximum electrification without wildfire. Spends twice as much as C for fewer deaths avoided.

F: Maximum Impact
4,602
Deaths Avoided
$13.9B
Cost

Everything: T2 + B2 + 30% wildfire + retire DTE. The first portfolio where building B2 appears. B2 is never cost-effective until you’ve exhausted wildfire and transport.

Efficient Frontier

29 Pareto-Optimal Portfolios

The efficient frontier traces the maximum deaths avoided at each budget level. Key patterns: T4 equity enters at $1B (concentrating reductions in LA/SJV is more cost-effective than statewide T2). Wildfire enters early and dominates the middle. T2 appears only after wildfire is saturated. Building B2 appears only at $13.9B.

Transport Wildfire Deaths Avoided Cost ($B) $/Death
T1 None 1,015 $0 Free
T4 Equity None 1,300 $1.0B $769K
T1 5% 1,738 $1.65B $949K
T4 Equity 5% 2,023 $2.65B $1.31M
T1 10% 2,462 $3.3B $1.34M
T4 Equity 10% 2,747 $4.3B $1.57M
T2 10% 2,829 $5.3B $1.87M
T1 20% 3,562 $6.6B $1.85M
T2 20% 3,929 $8.6B $2.19M
T2 30% 4,533 $11.9B $2.63M
T2 + B2 30% 4,602 $13.9B $3.02M

All portfolios include B1 baseline and retire DTE (both free). Select frontier points shown — full frontier has 29 Pareto-optimal combinations. T4 entries highlighted: equity-weighted reductions are more cost-effective than uniform T2 below $5B. $/Death is average cost per death from $0 — monotonically rising up the frontier as each marginal dollar buys fewer lives.

Finding
The portfolio analysis reverses the single-sector conclusion. The free lunch (T1 + B1 + retire DTE) avoids 1,015 deaths at $0. The marginal $2B is best spent on wildfire treatment, not transport acceleration. Building B2 never appears on the efficient frontier until $13.9B.

The recommended sequence: (1) Implement the free-lunch portfolio (T1 + B1 + retire DTE) immediately — the CRF choice doesn’t affect the T2 vs T1 ranking. (2) Fund the $0.5M age-stratified meta-analysis to tighten the benefit-magnitude band before allocating the marginal $2B. (3) Allocate the remaining budget to wildfire treatment on the current efficient-frontier evidence; revisit the transport-vs-wildfire split once the post-meta-analysis burden estimate is in hand.

Portfolio optimization over 4 sectors · Averaged Di/Krewski CRF · 10,000 MC draws · Pareto frontier enumeration · VSL = $11.6M (EPA 2024) · Wildfire cost mid-range ($33–100/acre) · Transport and building costs from CEC scenario definitions