Publications·September 22, 2023
In September 2023, with the support of Energy Foundation China, the Chinese Academy of Environmental Planning released this report discussing how China can co-manage criteria pollutants and carbon emissions from vehicles, with an estimation of the co-benefits.
Motor vehicles are a significant source of both carbon dioxide and atmospheric pollutants emissions, making their zero emissions of vital importance to China’s aspirations of achieving a “Beautiful China” and realizing the dual goals of carbon peaking by 2030 and carbon neutrality by 2060. This report researches on how much carbon and criteria pollution need to be reduced in the context of these aspirations, what the regional pathways are for cleaning motor vehicles from 2020 to 2035, and how significant are the corresponding carbon mitigation, pollution reduction, air quality improvement, and environmental health benefits.
Based on an analysis of the predicted emissions of carbon and criteria pollutants under various scenarios with different cleaning pathways and an assessment of the environmental health benefits associated with these different pathways, the report also offers policy recommendations to promote China’s transition toward zero emission motor vehicles.
This national study from the Chinese Academy of Environmental Planning sets out objectives, pathways, benefits, and policy recommendations for co-managing air pollution and carbon from China’s road-transport sector through 2035 (with a view to carbon neutrality by 2060). Framed by two strategic targets—carbon peaking before 2030 and a “Beautiful China” 2035 air-quality milestone—the report quantifies how fast emissions must fall, which policies deliver those cuts, how the air quality and health gains stack up, and what region-specific trajectories make sense. Methodologically, it couples WRF–CAMx air-quality modeling with GEMM/GBD health-impact estimation to attribute air and health improvements to the transport measures under different scenarios.
The challenge and the stakes
Despite large national progress since 2013, reaching 2035 goals requires additional reductions. Benchmarking against international experience, the report proposes a national PM₂.₅ annual mean of 25 μg/m³ by 2035 (and explores a more ambitious 15 μg/m³ case). Meeting the 25 μg/m³ goal implies, at all-sector level, national cuts by 2035 of −32% NOₓ and −32% VOCs, with commensurate reductions in primary PM₂.₅, SO₂, and NH₃ (vs 2020). The 15 μg/m³ case would require ~−61% NOₓ/VOCs and deeper multi-pollutant cuts across the economy.
Because traffic emissions occur close to people, health returns are especially large. The report treats transport as a priority domain for co-benefits: cutting fuel use and tightening standards lowers CO₂ and toxic co-pollutants together, with measurable mortality and morbidity reductions from PM₂.₅ and O₃ exposure.
What the modeling says China must do in road transport
The study develops two policy bundles: a Moderate and an Aggressive pathway (2020–2035), each combining four levers:
Tailpipe standards (upgrade to China 7 from 2026, then keep it as the tightest standard through 2035),
Fuel-economy improvements,
Transport restructuring (“road-to-rail/water” for freight), and
New-energy vehicle (NEV) penetration.
At the all-sector level, achieving 25 μg/m³ by 2035 translates to road-transport cuts of roughly −45% NOₓ, −40% VOCs, −30% primary PM₂.₅ vs 2020; for the 15 μg/m³ ambition they would need to be ~−80% NOₓ, −72% VOCs, −50% PM₂.₅. These are transport-sector shares derived from a 3-D optimization of environmental capacity and a space–sector “cross-contribution” matrix for 338 cities.
Vehicle stock, scenarios, and “what peaks when”
China’s motor-vehicle stock is projected to reach ~470 million by 2035 (≈410m passenger; ≈50m commercial), with regional heterogeneity in growth and baseline standards. The shares of national stock shift modestly toward less-developed regions over time (A: 41–45%; B: 32–34%; C: 23–25%).
CO₂ peaking:
Under the Moderate package, road-transport CO₂ peaks ~2027 at ~1.30 Gt, then is only slightly lower than 2020 by 2035.
Under the Aggressive package, CO₂ peaks ~2024 at ~1.218 Gt and falls ~29% by 2035 (to ~0.77 Gt).
By vehicle class, light passenger cars and heavy trucks dominate CO₂. These results show the Moderate path cannot meet the macro “2024–2026” peaking requirement; the Aggressive path can.
What drives the cuts? (decomposing contributions)
For CO₂:
NEV penetration is the single biggest lever nationally;
Fuel-economy improvements come next;
Road-to-rail/water matters particularly for heavy trucks;
Tightening pollutant standards (China 6→7) delivers negligible direct CO₂ reduction (they target criteria pollutants).
For criteria pollutants (NOₓ/VOCs/PM):
Standard upgrades dominate reductions—especially in the Moderate case;
NEVs and fuel-economy help (via less combustion);
Freight mode shift reduces heavy-duty diesel impacts and is disproportionately valuable for NOₓ.
How far and how fast to electrify?
The report sets NEV sales shares by vehicle type and year (national aggregates of region-specific trajectories):
Moderate: by 2030 new sales share: taxis/ride-hailing 95%, private light cars 50%, city buses 99%, large coaches 14%, light trucks 12%, heavy trucks 7%; by 2035: 98% / 60% / 99% / 20% / 19% / 16% respectively.
Aggressive: by 2030: 100% / 65% / 100% / 25% / 30% / 15%; by 2035: 100% / 95% / 100% / 40% / 50% / 40%. Buses and taxis essentially go all-electric in new sales by 2030–2035; trucks electrify later and slower.
Importantly, the study only counts use-phase emissions (no manufacturing/scrappage LCA), and it treats all NEVs as zero tailpipe in operation. Results are region-differentiated because income, climate, transit networks, and policy baselines vary.
Freight structure shift and standards
Because heavy-duty diesel trucks dominate NOₓ and contribute heavily to CO₂, the road-to-rail/water lever has outsize impact where feasible. The report sets region-specific targets for raising rail/water freight shares to 2035 (both Moderate and Aggressive), complementing China 7 implementation from 2026 (with further reductions in pollutant emission factors vs China 6, though incremental gains are smaller than the jump to 6).
Air-quality and health benefits
To translate emissions into public-health outcomes, the authors (i) compute sectoral emission scenarios, (ii) update the transport portion of the national emissions inventory, (iii) run WRF–CAMx over China (20 km grid) to obtain PM₂.₅/O₃ changes, and (iv) apply GEMM/GBD exposure–response functions to estimate avoided premature deaths and other endpoints. They then rank pathways by air-quality benefits and map contributions by measure every 5 years through 2035. The modeling framework also partitions national needs—−32% NOₓ/VOCs for the 25 μg/m³ goal—into transport-sector shares, ensuring the transport burden is commensurate with its contribution to PM₂.₅.
What this means for policy (2020–2035)
Lock in China 7 in 2026 and ensure in-use compliance (inspection/maintenance, defeat-device enforcement, and high-uptime after-treatment).
Push NEVs hardest in taxis and urban buses (where total-cost of ownership is favorable) and create bankable pilots for light trucks; for heavy-duty, combine NEV pilots with rail/water substitution and corridor charging/overhead or battery-swap trials.
Tighten fuel-economy standards for new light-duty vehicles (WLTC-based targets) and improve real-world efficiency via eco-driving, telematics, congestion pricing and parking policy.
Regionalize goals: faster electrification and standards turnover in Region A (higher income), with capacity building and infrastructure support to accelerate Regions B/C.
Measure what matters: publish transport emissions and ambient results in units with open data (and, where possible, CEMS/remote-sensing for in-use fleets), enabling accountability and calibrated course corrections.
Bottom line
To align road transport with 2024–2026 carbon peaking and 2035 clean-air goals, China needs the Aggressive package: fast NEV scale-up, China 7 and strong in-use enforcement, fuel-economy tightening, and freight structure shifts. It’s not just climate policy—the gains in PM₂.₅ and O₃-related health risk are substantial and quantifiable when modeled with WRF–CAMx and GEMM/GBD.
Keywords
Transport decarbonization; co-control (air + carbon); NEV penetration; China 7; NOₓ / VOCs / PM₂.₅; WRF–CAMx; GEMM / GBD; road-to-rail/water; fuel-economy standards; heavy-duty diesel; regional heterogeneity; public-health co-benefits; “Beautiful China 2035.