Recently, there has been an increased focus on black carbon and its potential impact on global warming. Diesel vehicles and equipment are one of the many sources of black carbon emissions. The Diesel Technology Forum recently published a new paper, "Climate Change, Black Carbon & Clean Diesel," that presents definitions, statistics and facts about black carbon. The paper explains how the introduction of new "clean diesel" technology is effectively shrinking black carbon emissions from U.S. transportation-related sources.
Over the last decade, the U.S. Environmental Protection Agency (EPA) has promulgated several new emissions standards for diesel fuel and diesel engines. While many, including the introduction of ULSD (ultra-low sulfur diesel) fuel and the on-highway diesel rule, have already been implemented, others rules that apply to off-road diesel equipment, like construction equipment, are being phased in over the next several years. As a result of changes in domestic fuel composition, along with advances in engine design and emissions control technology, black carbon emissions have been virtually eliminated from new "clean diesel" trucks and buses manufactured in the United States. Since 2004, these changes brought about a 99 percent reduction in black carbon emissions from heavy-duty diesel vehicles. Over the next several years, the latest clean diesel technology will also be used in the manufacture of most new off-road diesel engines/equipment.
Voluntary Efforts
With diesel's superior engine efficiency and the fuel's higher energy content, diesel equipment can do the same amount of work while burning less fuel than their gasoline counterparts, typically resulting in a notable reduction in greenhouse gas (GHG) emissions and less energy use. Many construction professionals are voluntarily taking steps to decrease their fuel consumption - through reduced equipment idling, equipment maintenance, and operator training - which further reduces energy consumption and GHG emissions. Some contractors are even opting to use alternative low-carbon fuels (like biodiesel and ethanol) that may significantly reduce GHG and other emissions when compared to petroleum diesel.
As DTF's report notes, installing diesel particulate filters on diesel engines/machines that are currently out in the field can reduce diesel particulate and black carbon emissions. However, for the construction industry, the costs of retrofitting equipment are prohibitive, and financial assistance is therefore needed to facilitate such an initiative. AGC has been working hard to secure federal funding for diesel retrofit:
- AGC's continues to urge Congress to fully fund EPA's Diesel Emissions Reduction Program, which provides grants/loans to government agencies and nonprofit groups (e.g., AGC Chapters) for reducing emissions from existing diesel engines through a variety of strategies.
- AGC also recommends the creation of a federal investment tax credit to provide a financial incentive for contractors to retrofit or replace their existing diesel powered equipment. Implementing a targeted investment tax credit would encourage contractors to upgrade their equipment to the current engine technology.
- AGC and the non-profit Clean Air Task Force jointly called on Congress to give state contracting officials both the authority and funding to require the use of clean construction equipment at federally-funded transportation projects. The groups are urging Congress to include the agreement in an upcoming six-year surface transportation reauthorization bill.