A new clean diesel revolution is underway, and its resultant benefit is a tool that port managers can immediately use to respond to community concerns about air quality.
In the 1990s, it became evident that diesel engine emissions needed to be reduced so that air quality improvements could continue. To meet this challenge, environmental regulators, engine manufacturers and diesel fuel producers went back to the drawing board to figure out how to marry diesel engine performance with reduced emissions.
What emerged was nothing short of revolutionary. Heavy-duty, clean diesel engines running on ultra-low sulphur clean diesel fuel have reduced particulate and NOx emissions by more than 98 per cent according to the United States Environmental Protection Agency (USEPA).
What is clean diesel?
Clean diesel is the result of a partnership between ultra-low sulphur diesel fuel, state-of-the-art engines and highly efficient control equipment, producing dramatically lower emissions. Clean diesel fuel is highly refined and contains very little sulphur. This clean fuel enables new diesel engines and emission control equipment to operate at peak efficiency to reduce emissions.
Innovative new engine technology also plays an important role in the clean diesel revolution. Engine manufacturers have incorporated better computer controls that allow for more precise fuel flows. Upgraded turbochargers and improved combustion chamber design also have led to reduced emissions.
Improved emission control equipment, including particulate filters, is the third component of the clean diesel revolution. Particulate filters can be used with new engines or they can be installed on older trucks and buses. In both cases, to work properly and avoid clogging, the engines must operate with ultralow sulphur fuel.
Clean diesel regulation
The United States Environmental Protection Agency (USEPA) has established clean diesel programmes that cover cleaner fuels and every type of diesel vehicle or equipment, whether new or in use today. Some states, most notably California, have established their own even more ambitious programmes.
In 2000, USEPA finalised its Clean Diesel Truck and Bus Rule for on-road vehicles that will result in a more than 90 per cent reduction in emissions by 2007. This rule requires new diesel emission control technologies and cleaner low-sulphur fuel to enable their successful operation.
In 2004, USEPA announced its Clean Air Non-road Diesel Rule for construction, agricultural, mining and other off-road equipment. This regulation uses the same clean diesel strategy of combining particulate filters, new engine technology and cleaner fuels to achieve emissions reductions of more than 90 per cent. It’s scheduled to be in place by 2010.
Locomotives and marine engines are also on USEPA’s radar screen. The agency is considering new emissions standards aimed at these engines modelled after highway and off-road programmes.
The California Air Resources Board (CARB) has adopted and continues to adopt regulatory requirements that specifically address diesel emissions. These regulatory requirements include fleet rules for transit agencies, plus stationary and portable engines. Many of these California regulations are more stringent and aggressive than the federal regulations in both the level of compliance and the timeline for implementation.
CARB is also assessing regulatory requirements to address diesel emissions associated with port activities such as off-road engines and equipment, harbor craft, auxiliary marine engines, cargo handling equipment, locomotives and truck idling activities.
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