Biodiesel feedstock
| Plant oils |
|---|
 |
| Types |
| Uses |
| Components |
A variety of oils can be used to produce biodiesel. These include:
- Virgin oil feedstock; rapeseed and soybean oils are most commonly used, soybean oil alone accounting for about ninety percent of all fuel stocks; It also can be obtained from field pennycress and Jatropha other crops such as mustard, flax, sunflower, palm oil, hemp, and even algae show promise (see List of vegetable oils for a more complete list);
- Waste vegetable oil (WVO);
- Animal fats including tallow, lard, yellow grease, chicken fat, [1]
and the by-products of the production of Omega-3 fatty acids from fish oil.
- Algae, which can be grown using waste materials such as sewage[2]
and can also be grown without displacing land currently used for food production.
Worldwide production of vegetable oil and animal fat is not yet sufficient to replace liquid fossil fuel use. Furthermore, some environmental groups object to the vast amount of farming and the resulting over-fertilization, pesticide use, and land use conversion that they say would be needed to produce the additional vegetable oil.
Many advocates suggest that waste vegetable oil is the best source of oil to produce biodiesel. However, the available supply is drastically less than the amount of petroleum-based fuel that is burned for transportation and home heating in the world. It is important to note that one unit of waste oil is not equivalent to one unit of biodiesel.[citation needed]
Although it is economically profitable to use WVO to produce biodiesel, it is even more profitable to convert WVO into other products such as soap. Therefore, most WVO that is not dumped into landfills is used for these other purposes. Animal fats are similarly limited in supply, and it would not be efficient to raise animals simply for their fat. However, producing biodiesel with animal fat that would have otherwise been discarded could replace a small percentage of petroleum diesel usage. Currently, a 5-million dollar plant is being built, with the intent of producing biodiesel from some of the estimated 1.05 million tonnes (2.3 billion pounds) of chicken fat[3] produced annually the local Tyson poultry plant, though insiders estimate a potential production of 1.1 billion litres (300 million gallons) of fuel from the chicken fat feedstock. [1]The estimated transportation diesel fuel and home heating oil used in the United States is about 190 billion litres (50 billion US gallons) according to the Energy Information Administration, US Department of Energy - [4]. Waste vegetable oil and animal fats would not be enough to meet this demand. In the United States, estimated production of vegetable oil for all uses is about 11 million tonnes (24 billion pounds) or 11 billion litres (3 billion US gallons), and estimated production of animal fat is 5.3 million tonnes (12 billion pounds).[5]
Biodiesel feedstock plants utilize photosynthesis to convert solar energy into chemical energy. The stored chemical energy is released when it is burned, therefore plants can offer a sustainable oil source for biodiesel production. Most of the carbon dioxide emitted when burning biodiesel is simply recycling that which was absorbed during plant growth, so the net production of greenhouse gases is small.
Feedstock yield efficiency per acre affects the feasibility of ramping up production to the huge industrial levels required to power a significant percentage of national or world vehicles. The highest yield feedstock for biodiesel is algae, which can produce 250 times the amount of oil per acre as soybeans.[6]
References
Footnotes
Biodiesel feedstock
| Plant oils |
|---|
| |
| Types |
| Uses |
| Components |
A variety of oils can be used to produce biodiesel. These include:
- Virgin oil feedstock; rapeseed and soybean oils are most commonly used, soybean oil alone accounting for about ninety percent of all fuel stocks; It also can be obtained from field pennycress and Jatropha[1] other crops such as mustard, flax, sunflower, palm oil, hemp, and even algae show promise (see List of vegetable oils for a more complete list);[2]
- Waste vegetable oil (WVO);
- Animal fats including tallow, lard, yellow grease, chicken fat,[1] and the by-products of the production of Omega-3 fatty acids from fish oil.
- Sewage. A company in New Zealand has successfully developed a system for using sewage waste as a substrate for algae and then producing bio-diesel.[3]
Worldwide production of vegetable oil and animal fat is not yet sufficient to replace liquid fossil fuel use. Furthermore, some environmental groups object to the vast amount of farming and the resulting over-fertilization, pesticide use, and land use conversion that they say would be needed to produce the additional vegetable oil.
Many advocates suggest that waste vegetable oil is the best source of oil to produce biodiesel. However, the available supply is drastically less than the amount of petroleum-based fuel that is burned for transportation and home heating in the world. It is important to note that one unit of waste oil is not equivalent to one unit of biodiesel.[citation needed]
Although it is economically profitable to use WVO to produce biodiesel, it is even more profitable to convert WVO into other products such as soap. Therefore, most WVO that is not dumped into landfills is used for these other purposes. Animal fats are similarly limited in supply, and it would not be efficient to raise animals simply for their fat. However, producing biodiesel with animal fat that would have otherwise been discarded could replace a small percentage of petroleum diesel usage. Currently, a 5-million dollar plant is being built, with the intent of producing biodiesel from some of the estimated 1.05 million tonnes (2.3 billion pounds) of chicken fat[4] produced annually the local Tyson poultry plant, though insiders estimate a potential production of 1.1 billion litres (300 million gallons) of fuel from the chicken fat feedstock. [5]
The estimated transportation diesel fuel and home heating oil used in the United States is about 190 billion litres (50 billion US gallons) according to the Energy Information Administration, US Department of Energy - [6]. Waste vegetable oil and animal fats would not be enough to meet this demand. In the United States, estimated production of vegetable oil for all uses is about 11 million tonnes (24 billion pounds) or 11 billion litres (3 billion US gallons), and estimated production of animal fat is 5.3 million tonnes (12 billion pounds).[7]
Biodiesel feedstock plants utilize photosynthesis to convert solar energy into chemical energy. The stored chemical energy is released when it is burned, therefore plants can offer a sustainable oil source for biodiesel production. Most of the carbon dioxide emitted when burning biodiesel is simply recycling that which was absorbed during plant growth, so the net production of greenhouse gases is small.
Feedstock yield efficiency per acre affects the feasibility of ramping up production to the huge industrial levels required to power a significant percentage of national or world vehicles. The highest yield feedstock for biodiesel is algae, which can produce 250 times the amount of oil per acre as soybeans.[8]