Diesel: Gasoline’s Dirty Cousin? Or the Little Engine that Keeps American Power Reliable By: Michael D. Mankowski.

Diesel: Gasoline’s Dirty Cousin?

Or the Little Engine that Keeps American Power Reliable

By: Michael D. Mankowski

How is Diesel Different from Gasoline?(1)

• Diesel is a petroleum-based fuel with a higher energy content than gasoline.– contains about 30% more energy per gallon as

compared to gasoline.

• Diesel is a safer fuel than gasoline or other alternatives.– less flammable and explosive than gasoline due to

lower combustibility.

How is Diesel Different from Gasoline?(2)

• Diesel is Cheaper than Gasoline– Current Cost of a Gallon of Gasoline and Diesel

• Gasoline = $1.78

• Diesel = $1.65

How a Diesel Engine Works

Compression Instead of Spark

• Diesel engines ignite fuel with compression – The piston stroke in a diesel engine results in

a compression of the fuel air mixture so intense that it combusts spontaneously.

• Gasoline engines ignite fuel with spark plugs

• Gasoline engines inject fuel during the intake stroke, Diesel during the Compression Stroke.

Three Ways of Injecting Fuel

1. Crankshaft Driven Fuel Pump

2. Common-rail Fuel Injection

3. Unit Injection

Crankshaft Driven Fuel Pump

A fuel distribution pump geared to the crankshaft to sends a pulse of pressurized fuel down a dedicated pipe to each cylinder at a predetermined point in the compression stroke.

Common-rail Fuel Injection(1)

• Uses a pump to deliver pressurized fuel to all the injectors and than relies on electronically controlled valves at each injector to open as needed.

• Used on most modern Diesel Engines

Common-rail Fuel Injection(1)

Unit Injection

• Delivers low-pressure fuel to each cylinder and relies on the injector to generate its own pressure mechanically.

• Most heavy-duty diesels use unit injectors, which can be equipped with an electronic control valve to regulate the amount and timing of the injection.

Misconceptions About Diesel

• It’s Dirty

• It Causes a lot of Pollution

• It has Limited Uses

Benefits of Diesel

• A well maintained diesel engine usually emits lower levels of carbon monoxide, hydrocarbons and carbon dioxide than gasoline engines.

• Better fuel economy,

• Increased durability for longer engine life.

Problems with “Old” Diesel Technologies

• High Sulfur Content of Fuel

• High NOx Emissions

• High Particulate Matter Emissions– The “Black Smoke” everyone sees

• Noisy Engines

Sulfur Content

• Diesel fuel available in the U.S. currently contains from 340 ppm of sulfur to 140 ppm in California.

• European Standards are much lower– As low as 10 ppm in Germany and Sweden

NOx Emissions

• High cylinder pressure and temperature with excessive air is the recipe for making NOx

• Because of excess air in diesel engines, current catalytic can’t scrub out NOx

Particulate Matter

• Unburned fuel in the compression ignition process becomes soot, a pervasive form of particulate matter.

Clean Diesel

• Clean diesel is an evolutionary systems-based process that combines advancements in diesel engines, cleaner burning fuels and emissions control system, all working and optimized together.

What Makes Diesel Clean?

• The Three Pillars of Clean Diesel Technology:– cleaner-burning fuels– state-of-the-art engines– effective emissions-control systems

Cleaner Burning Fuels

• The newest in diesel fuels is called Ultra-low Sulfur Diesel (ULSD)– Ultra-low sulfur diesel fuel is a specially refined diesel

fuel that has dramatically lower sulfur content than regular diesel and can be used in any diesel engine just like regular diesel fuel.

• Today, the sulfur content of ULSD ranges from 15 to 30 parts per million. Regular diesel has a maximum of 500 parts per million of sulfur.

How Does ULSD Help?

• Reduces sulfate emissions

• Allows the use of particulate traps and catalytic converters

• Lowers engine maintenance costs

• Easy to convert to– No retrofitting required

• Only costs a few cents more

State of the Art Engines

• New Engine Technologies– Electronic Controls– Common-rail Fuel Injection– Variable Injection Timing– Improved Combustion Chamber Configuration– Turbocharging

New Pollution Controls

• Particulate Traps

• Oxidation Catalysts

So What does all of this Have to do with Reliability?

• Better diesel technology means greater efficiency

• Efficient diesel technology is required in order to comply with upcoming environmental legislation

• America wouldn’t be able to function without diesel

Diesel is an Integral Part of America

• Diesel is used in many different industries – Transportation

– Shipping

– Agriculture

– Mining

– Energy Production

– Safety

– Homeland Security

– Defense

Electrical System

• Almost all of these industries play a part in making sure that the electrical system in the U.S. stays intact

• Power plants can’t produce power without fuel, and most of that fuel is produced and move by diesel

• Diesel also plays an integral part in providing power when disaster strikes, or the major electrical systems fail

How Diesel Effects Reliability

• Backup Generators• Equipment• Transportation• Shipping

Backup Generators(1)

• Many Sources use Diesel Generators for Backup power– Hospitals– Nuclear Plants– Public Utilities– Food Storage

Backup Generators(2)

• Diesel generators kick on within seconds, providing immediate, full strength power when it is needed most

Equipment

• Most of the nonroad equipment used in the United States is powered by Diesel– Snow plows– Mining Machinery– U.S. Military Vehicles– Emergency Response Vehicles

Public Transportation

• In 1998, 95% of the nation’s full-sized transit buses were powered by diesel

• Close to 60% of America’s elementary and secondary schools used diesel to power the buses that take children to school everyday

Shipping

• 94% of all goods shipped in the U.S. are shipped using diesel power

• Diesel dominates the trucking, railroad, boat and barge industries

Legal Framework for Diesel

• Legislation heavily influences the use of diesel

• Upcoming legislation could eliminate diesel use if it weren’t for ongoing technological development and improvement

New Engines

• Engine manufacturers have been subject to nationwide, federally-enforceable air pollution standards under the Clean Air Act since 1970

• In 1970, the CAA mandated 90% reductions for levels of carbon monoxide (CO), hydrocarbons (HC), and oxides of nitrogen (N0x) in light-duty vehicles by 1976.

• In 1977, further amendments to the CAA mandated a 90% reduction in CO and HC for heavy-duty vehicles by 1984, and a 75% reduction in NOx by 1985.

New Engines (2)

• In 1990, further amendments to the CAA were established and EPA recently enacted regulations that will reduce NOx and non-methane hydrocarbons (NMHC) emissions from heavy-duty diesel engines by over 50% from 1998 levels.

• These standards dramatically reduced the amount of emissions form diesel engines, but tougher standards are on the way.

Regulation of New Engines and Fuels (1)

• In 2001, EPA created a new rule:– Control of Air Pollution From New

Motor Vehicles: Heavy-Duty Engine and Vehicle Standards and Highway Diesel Fuel Sulfur Control Requirements

• This rule controls both new diesel engines and the sulfur content of diesel fuels

Regulation of New Engines and Fuels (2)

• New Standards for Particulate Matter and NOx

– 90% reduction of current standard for PM– 95% reduction for NOx

• 97 % reduction of Sulfur content • It sets new standards that will go into effect

in model year 2007 for the trucks and mid 2006 for the fuel

Durability and Maintenance

• EPA’s 1997 rulemaking for enhanced emission standards for heavy-duty diesels included several provisions to enhance durability requirements for emissions performance. – Increased useful life mileage from 290,000 to 435,000.

– Enhanced Inspection and Maintenance requirements.

– Enhanced emissions defect and performance warranties.

Regulation of Existing Engines

• In 1994, EPA established a stringent three-tiered emissions reduction scheme that subjects all non-road engines - regardless of size -- to progressively more stringent emission standards and will radically reduce emissions from non-road engines by more than 70% in many cases.

• Tier 2 and Tier 3 standards, which include large diesel engines, were made more stringent in 1998

• NOx and Particulate Matter emission standards were reduced up to 2/3rds for some applications

Conclusion(1)

• Diesel should continue to be developed because it is important to most of the industries in the U.S.

• Much progress has been made in making diesel a more efficient and clean fuel choice.

• Most of the problems associated with diesel in decades passed have been eliminated or reduced

• The diesel engines of today are cleaner, more efficient, and more powerful than the ones built even ten years ago