Carbon Tracker: Automakers' Carbon Intensity Now Rivals Big Oil

Carbon Tracker's Oil Companies in Disguise report reveals a widespread 33% carbon gap between automakers' declared metrics and real-world vehicle lifecycle emissions, identifying legacy automotive investments as structurally comparable in carbon intensity to traditional oil and gas assets. This global transparency shortfall creates critical commercial friction for Mexico's massive export manufacturing base, which remains heavily reliant on the hybrid models most prone to underestimated lifetime usage assumptions. As Mexico enters its first mandatory reporting cycle under NIS sustainability standards, local auto manufacturers face mounting valuation risks, grid-efficiency scrutiny, and tightening international legal liabilities like the EU's greenwashing directives ahead of upcoming USMCA trade updates.

A report published by Carbon Tracker, Oil Companies in Disguise, found that traditional automakers generate carbon emissions at a level comparable to oil and gas companies, largely because they are systematically underestimating the lifetime emissions of the vehicles they sell. At least 17 of the world's largest manufacturers, representing 80% of global vehicle sales, showed discrepancies of up to 33% between declared emissions and actual emissions derived from vehicle use, according to the analysis.

"Flawed emissions reporting by automakers obscures the reality that a dollar invested in traditional auto companies is, in many cases, as carbon-intensive as a dollar invested in oil and gas," said Ben Scott, Head of Energy Demand, Carbon Tracker.

Carbon Tracker found that several automakers post carbon intensity levels higher than those of leading oil and gas companies. Mazda and Mitsubishi showed the highest emissions intensities, at 10.2 and 9.9t of CO2 equivalent per enterprise value (CO2e/EVIC) respectively, compared to Shell, the oil and gas company with the highest intensity among majors, at a factor of four.

The report attributes this carbon gap to the widespread use of unrealistic assumptions about total vehicle lifetime mileage, optimistic estimates of plug-in hybrid (PHEV) usage patterns, and the exclusion of upstream fuel production emissions from reported figures.

General Motors showed the largest absolute emissions gap in the sector, driven by a combination of high-intensity products and a more significant disclosure deficit. Subaru showed the largest relative discrepancy, with emissions potentially understated by more than 200% due to reporting assumptions that do not reflect actual usage. By contrast, Renault and Stellantis emerged as transparency leaders, with their reported figures aligning closely with Carbon Tracker's independent estimates.

Carbon Tracker frames automakers as the gatekeepers of future oil demand: passenger vehicles represent the largest single source of global oil demand, and every internal combustion or hybrid vehicle sold today locks in 10 to 20 additional years of fuel consumption. That framing reframes the climate debate around the auto sector — not as a question of whether electrification is happening, but of whether the pace and honesty of that transition matches what companies are publicly claiming.

The report adds a concrete data point to the broader greenwashing scrutiny that has intensified across the energy and industrial sectors in 2026, including the documented gap between PEMEX's sustainability reporting and its operational safety record, and the EU's new Empowering Consumers for the Green Transition Directive, which prohibits unverifiable environmental claims starting in September.

Mexico's Position: A Manufacturing Hub With a Stake in Both Sides

Mexico's relevance to this report is structural, not incidental. The country is one of the world's largest vehicle manufacturing bases, producing for export under nameplates that include several of the companies named in Carbon Tracker's analysis, while simultaneously experiencing one of the fastest electrification curves in its own domestic market.

One in every eight light vehicles sold in Mexico during the first four months of 2026 was electrified. According to RAIAVL data, 60,402 electrified vehicles were sold between January and April out of 500,512 total light-vehicle sales, with electrified models accounting for more than 12% of the market, up from 9.6% in 2025. Hybrid electric vehicles continued to dominate with 42,022 units sold, while battery electric vehicle sales reached 9,087 units, growing 71% year-over-year.

That growth, however, occurs within a vehicle mix still dominated by hybrids, the precise category Carbon Tracker's report identifies as the source of the largest reporting discrepancies, given "optimistic estimates of plug-in hybrid usage patterns." Mexico's electrified vehicle market reached 16,374 units sold in March 2026 alone, a 33.9% year-over-year increase, with monthly volumes having quadrupled since 2021 according to AMIA, AMDA, and INA.

The Energy Source Question

Carbon Tracker's report focuses on vehicle-level emissions reporting, but Mexican industry experts have long flagged a parallel issue: the carbon intensity of the electricity that charges those vehicles. Ivette Castillo, General Manager, GSI LAM at GE Grid Solutions, has noted that in less efficient energy generation matrices, EVs can reduce emissions by approximately 25%, a figure that can surpass 75% with more effective generation matrices.

That distinction is directly relevant to Mexico, where natural gas-fired generation supplies approximately 65% of the electricity grid and clean generation sits at roughly 23.4%, well short of the 38% target for 2030. An electric vehicle charged on Mexico's current grid mix delivers meaningfully less emissions benefit than the same vehicle would in a market with a cleaner generation profile, a nuance that, much like the automaker disclosure gaps Carbon Tracker identified, rarely appears in marketing claims about EV adoption.

Carbon Tracker's central argument is that automaker carbon disclosures, taken at face value, are misleading institutional investors who allocate capital under the assumption that traditional auto manufacturing carries materially lower transition risk than oil and gas. The data suggests that assumption does not hold for several of the largest manufacturers by sales volume.