The country’s expanding railway network could sharply reduce the transport sector’s carbon footprint, with upcoming rail projects expected to cut hundreds of thousands of tons of carbon dioxide emissions annually as more commuters shift away from private vehicles.

The Department of Transportation (DOTr) said Monday that existing rail lines already generate significantly lower emissions per passenger than private cars, strengthening the economic and environmental case for expanding mass transit in congested urban areas.

Transportation Secretary Giovanni Lopez said the government is pushing for more sustainable and commuter-focused transport systems.

“The directive is to make our transportation system sustainable. That is why we at the DOTr are pushing for what we call commuter-centric transport, such as trains, which can carry more passengers. If more people take trains instead of private vehicles, we can significantly reduce carbon emissions on the roads,” Lopez said.

Citing National Rail UK's Greener Travel data, the DOTr said car travel generates 167 grams of carbon dioxide (CO₂) per kilometer, compared with 35 grams per passenger per kilometer for rail.

Even assuming two passengers in a private vehicle, emissions from car travel would amount to about 83.5 grams per passenger per kilometer—more than twice that of rail.

The MRT-3, LRT-1, LRT-2 and Philippine National Railways collectively contribute to an estimated net reduction of 74,781 tons of CO₂ emissions annually, equivalent to an average reduction of 50 percent, according to the DOTr.

The impact is expected to grow as major railway projects come online.

The North-South Commuter Railway is projected to reduce emissions by more than 150,000 tons annually, more than double the estimated reduction from the four existing rail lines.

MRT-7, targeted to open in the second quarter of 2027, is expected to reduce emissions by more than 60,000 tons annually, or about 58% compared with private car travel.

The Metro Manila Subway, meanwhile, could cut annual emissions by more than 70,000 tons, equivalent to a reduction of as much as 63%.

Expanding mass transit could help ease the economic cost of Metro Manila's chronic congestion.

A Japan International Cooperation Agency study estimated that traffic costs the Philippine economy P3.5 billion daily. Without government intervention, the losses could rise to as much as P5.4 billion per day by 2035.