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January 04, 2016   |   Diesel Technology Forum

Policy Insider

Carbon Emissions, COP21 and Diesel Technology

Find out how advances in one of the oldest technologies will help cool a warming planet.

As 2015 came to a close, representatives of over 180 countries reached a new agreement to limit greenhouse gas emissions and hold a warming planet to just 2 degrees Celsius by the end of the century.  The new agreement, reached at the conclusion of the 21st meeting of the Conference of Parties (COP21) in Paris, relies on the “Intended Nationally Determined Contribution” or INDC. According to the agreement, each member state is expected to live up to its submitted intended commitment to reduce their share of GHG emissions.


The INDC for the U.S. calls for a reduction of greenhouse gas emissions between 26 percent and 28 percent by 2025 relative to a 2005 baseline. In order to achieve this target, the INDC submitted by the U.S. references existing regulation as well as proposed regulation. Specifically, those policies pertaining to fuel economy targets for passenger cars (CAFE standards), heavy-duty vehicles (Phase 1) as well as the proposed fuel economy rules for heavy-duty vehicles (Phase 2) and the emission reduction from power generation (Clean Power Rule). Other policies referenced that contribute a smaller amount of emission reduction include rules for hydrofluorocarbon and methane emissions among others. 

New technology diesel engines will be critically important to meet these keystone emission reduction targets established under the U.S. INDC.  As diesel engines power over 95 percent of the heavy-duty commercial vehicle fleet, advancements under the Phase 1 rule is estimated to reduce GHG emissions by 270 million tons between 2014 and 2018 while the proposed Phase 2 rule is expected to save one billion tons of GHG emissions between 2021 and 2027, according to the U.S. Environmental Protection Agency. 

In addition to the INDC, many states, municipalities and other “sub-national governments” announced efforts to cut GHG emissions. Carbon reduction included in these pledges typically do not count towards the INDC but unofficially contribute toward GHG emission reduction. Again, new technology diesel engines and fuel will play a critical role.  Most notably, some of America’s largest transit fleets of buses and commuter rail are taking note of the fuel savings and near zero emissions benefits of new technology diesel and are investing in the switch.  You can read more about that here

One of the unique attributes of diesel engines is the capability to operate on high quality blends of bio-based diesel fuel. In fact, the diesel engine as patented by Rudolph Diesel a century ago was intended to operate on peanut oil. Equally impressive strides have been made to advance bio-based diesel fuel quality that greatly contributes to further greenhouse gas emission reduction and clean air benefits. Already in California, the City of San Francisco has transitioned away from petroleum diesel fuel and is exclusively using renewable diesel fuel in all city-owned diesel vehicles and equipment. Just across the Bay, the City of Oakland announced that it also intends to use renewable diesel fuel in an effort to reduce the city’s carbon footprint.

Meanwhile, the City of New York is already using higher quantities of both biodiesel in its enormous fleet of over 9,000 diesel powered vehicles and equipment. The use of new and newer diesel engines powered by greater blends of biodiesel and renewable diesel make up the greatest contribution towards greenhouse gas emission reduction in the City’s “Clean Fleet” initiative. The U.S. Environmental Protection Agency classifies renewable diesel fuel that is derived from waste agricultural products such as soy and animal fats, as an advanced biofuel capable of achieving a reduction in greenhouse gas emissions by at least 50 percent. In fact, the greenhouse gas emission reduction from the use of newer diesel engines and bio-based diesel fuel exceeds that of the effort to transition electric light duty vehicles in the city’s fleet.

The use of clean diesel engines and advanced biofuel is not just a U.S. success story. States, provinces and municipalities and businesses across the globe are making the investment in clean diesel that will provide clean air for everyone and help cool a warming planet.



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Ezra Finkin
Director, Policy

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