Reduce Emissions: Cleaner Diesels

Diesel fuel is a type of fuel whose energy density and viscosity are higher than that of gasoline fuel. Generally diesel fuel, and thus diesel engines, are more fuel-efficient, because more energy is created per gallon of diesel than per gallon of gasoline. While diesel is more efficient, there are problems associated with its use, such as the fact that burning diesel fuel generates chemicals that can contribute to both smog and acid rain. Its advantages however, are prodigious; including the fact that diesel produces less carbon dioxide and carbon monoxide emissions. Also, while the traditional petroleum-based diesel, or petrodiesel, is problematic to the environment, there are potentially cleaner diesel fuel alternatives available, such as certain forms of biodiesel. When it comes to protecting the environment, the primary advantage of diesel over gasoline is the variety of methods that are available to produce it.

How Is Diesel Different From Regular Or Premium Gas?

Petroleum-based diesel is a heavier type of fuel than regular or premium gasoline, with a 10 percent higher density and energy output, or British Thermal Units (BTU) per gallon. Diesel fuel runs on the principle of compression ignition, in which the diesel engine uses hot compressed air to ignite the fuel which then powers the engine. Gasoline engines use a spark plug which ignites the fuel to power the engine. One advantage of diesel fuel is that chaotic ignition, also known as “knocks”, are less common in diesel engines than gasoline engines. Another advantage is that diesel fuel is more energetic, which means it produces more mileage per gallon than gasoline. One considerable disadvantage of using a diesel engine over a gasoline engine is that diesel fuel can become too viscous during cold weather. This can make it difficult to inject the fuel into the engine, thus making it difficult to start the vehicle.

How Does Diesel Affect The Environment?

When it comes to contributing to global warming, diesel produces more greenhouse gases than gasoline, but its fuel usage efficiency more than offsets this disadvantage. Diesel fuel, unlike gasoline, produces a high amount of sulfur dioxide and nitrogen oxide. Nitrogen oxide, also called noxious emissions, contributes to smog and potentially carcinogenic particulates. It is a mix of nitric oxide and nitrogen dioxide, the latter of which is highly toxic in nature. Sulfur dioxide can turn into sulfuric acid and contribute to acid rain. Diesel fuel also produces soot, which contributes to smog. The production of diesel fuel can also lead to spills, which can damage the environment and pose a risk to animals, although it is a lower risk than a crude oil spill. Even biodiesel is not completely safe for the environment in the event of a spill, because the fuel is oily and can mire fish or collect in fur and feathers, weighing them down and leaving them vulnerable to suffocation or attack by predators.

What Are Some Ways To Reduce Emissions?

One of the biggest problems with diesel fuel is its emissions of sulfur dioxide. Regulations passed in the United States and other countries require that diesel fuel be processed to reduce sulfur emissions. As a result, diesel fuel produced and sold in the United States must meet the Ultra-Low Sulfur Diesel (ULSD) standards, which are continually updated by the government. Diesel particulate filters can also be installed onto existing vehicles to cut down on the release of particulate matter into the air. Biodiesel, especially diesel fuel made from used vegetable oil, is another potential way to reduce diesel emissions. Studies show that vegetable oil produces nearly 90 percent fewer emissions than petrodiesel and furthermore, its production results in little to no useless or wasted material. The Fischer-Tropsch method of biomass-based diesel production is another method of producing lower-emissions diesel fuel. Fuel produced by this process results in a further reduction of potentially carcinogenic particulate matter and smog emissions than regular petroleum-based diesel, as well as the complete lack of sulfur production.

How To Obtain Cleaner Diesel Fuel

Getting access to cleaner diesel fuel can be as simple as picking up used vegetable oil from restaurants or recycling used cooking oil from home. Used vegetable oil must first go through a filter in order to reduce its viscosity, as well as a strainer to remove particulates that accumulated in the oil during its use in the cooking of food. A growing number of gasoline stations around the United States and in Europe also offer biodiesel for motorists and trucks. In this case biodiesel comes in blends of either 100 percent biodiesel, B80 (80 percent biodiesel and 20 percent petrodiesel), B20 (20 percent biodiesel and 80 percent petrodiesel), or other combinations.

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