Fact of Biodiesel Emissions

we commonly hear that Biodiesel have low emission than gasoline and diesel fuel,how much exactly the emission of Biodiesel? below is data sheet from various organization that's tested Biodiesel emission.

Biodiesel is the first and only alternative fuel to have a complete evaluation of emission results and potential health effects submitted to the U.S. Environmental Protection Agency (EPA) under the Clean Air Act Section 211(b). These programs include
the most stringent emissions testing protocols ever required by EPA for certification of fuels or fuel additives. The data gathered complete the most thorough inventory of the environmental and human health effects attributes that current technology will
allow.

1. the fact of biodiesel emision based on test by EVA are
The ozone (smog) forming potential of biodiesel hydrocarbons is less than
diesel fuel
2. The exhaust emissions of carbon monoxide from biodiesel are on average 48 percent lower than carbon monoxide emissions from diesel.
3. The exhaust emissions of total hydrocarbons (a contributing factor in the localized formation of smog and ozone) are on average 67 percent lower for biodiesel than diesel fuel
4. NOx emissions from biodiesel increase or decrease depending on the engine family and testing procedures.
5. Biodiesel reduces the health risks associated with petroleum diesel.
Biodiesel emissions show decreased levels of polycyclic aromatic hydrocarbons (PAH) and nitrated polycyclic aromatic hydrocarbons (nPAH), which have been identified as potential cancer causing compounds

or you can download full report at
www.biodiesel.org/pdf_files/fuelfactsheets/emissions.PDF

Compared to diesel, biodiesel produces no sulfur, no net carbon dioxide, up to 20 times less carbon monoxide and more free oxygen. Biodiesel has the following emissions characteristics when compared with petroleum diesel fuel:

1. Reduction of carbon dioxide emissions (CO2) by 100%
2. Reduction of sulfur dioxide (SO2) emissions by 100%
3. Reduction of soot emissions by 40-60%
4. Reduction of carbon monoxide (CO) emissions by 10-50%
5. Reduction of hydrocarbon (HC) emissions by 10-50%
6. Reduction of all polycyclic aromatic hydrocarbons (PAHs) and specifically the reduction of the following carcinogenic PAHs:

1. Reduction of phenanthren by 97%
2. Reduction of benzofloroanthen by 56%
3. Reduction of benzapyren by 71%
4. Reduction of aldehydes and aromatic compounds by 13%
5. Reduction or increase in nitrous oxide (NOx) emissions by 5-10% depending on the age and type of engine.

http://www.biodieselamerica.org/what_is_biodiesel

Studies on biodiesel emissions have been conducted for almost 20 years. In that time biodiesel has undergone the most rigorous testing of any alternative fuel, having been the first and only fuel to be evaluated by the EPA under the Clean Air Act Section 211(b). This study examined the impact of hundreds of regulated and non-regulated exhaust emissions, as well as the potential health effects of these emissions. Some of these results are summarized below.

Average Exhaust Emissions for 100% Biodiesel Compared to Petroleum Diesel Fuel*
Regulated Exhaust Emissions B100
Particulate Matter -47%
Carbon Monoxide -48%
Total Unburned Hydrocarbons -67%
Nitrogen Oxides +10%
Non Regulated Emissions
Sulfates -100%
Polycyclic Aromatic Hydrocarbons (PAH) -80%
Nitrated Polycyclic Aromatic Hydrocarbons (nPAH) -90%
Speciated Hydrocarbons Ozone Forming Potential -50%

Explanation of Emission Types

Particulate Matter (Black Smoke)
Emissions of particulate matter have been linked to respiratory diseases and are generally considered to be a human health hazard. Emissions of particulate matter are reduced with biodiesel by 47%.

Carbon Monoxide
Carbon Monoxide is a poisonous gas. Reduced with biodiesel by 48%.

Total Unburned Hydrocarbons
Compounds which contribute to localized formation of smog. Reduced with biodiesel by 67%.

Nitrogen Oxides
Compounds which contribute to localized formation of smog. The average increase of Nitrogen oxide emissions from biodiesel is 0%-10%, depending upon the test used in obtaining the data.

Sulfates
Sulfates are major contributors to acid rain. These emissions are practically eliminated when using biodiesel.

Polycyclic Aromatic Hydrocarbons (PAH and nPAH)
These compounds have been identified as carcinogenic (cancer causing) compounds. Biodiesel reduces emissions of these compounds by up to 85% for PAH compounds and 90% for nPAH compounds.

Speciated Hydrocarbons
These compounds contribute to the formation of localized smog and ozone. The potential for smog formation from speciated hydrocarbons is reduced by 50% when using biodiesel.

Life Cycle Reduction of CO2
Biodiesel helps reduce the risk of global warming by reducing net carbon emissions to the atmosphere. When biodiesel is burned, it releases carbon dioxide to the atmosphere, but crops which are used to produce biodiesel take up carbon dioxide from the atmosphere in their growth cycle. A joint study conducted by the U.S. Department of Agriculture, and the U.S. Department of Energy determined that biodiesel reduces net carbon dioxide emissions to the atmosphere by 78.5% compared with petroleum diesel fuel.
http://www.nrel.gov/docs/legosti/fy98/24089.pdf

Other Fact
• This same phenomenon reduces air toxics, because the air toxics are
associated with the unburned or partially burned HC and PM emissions.
• Testing has shown that PM, HC, and CO reductions are independent of
the feedstock used to make biodiesel.
http://biofuels.coop/pdfs/9_emissions.pdf