Biodiesel

CHAPTER FOURTEEN

Biodiesel

CHAPTER 14

Biodiesel
INTRODUCTION
“Biodiesel” — diesel fuel made from animal or vegetable materials — is an alternative fuel that has been used in motor vehicles since the beginnings of the automobile industry. It can be substituted for petroleum-based diesel fuel (“petrodiesel”) in diesel engines. Vehicles using biodiesel emit fewer pollutants thanpetrodiesel, although they also generally get slightly fewer miles per gallon. The basic process for making fuel from organic matter has not changed since it was invented in the nineteenth century. The process, called transesterification, forces vegetable oil or animal fat to react with a catalyst (usually sodium hydroxide) and methanol or ethanol to produce glycerol and fatty acid esters, the latter beingthe actual chemical name for biodiesel (Exhibit 14-1). Transesterification originally was used to obtain glycerol for soap; what we now call biodiesel was a byproduct of the soap-making process. Many products, including peanut oil, hemp oil, corn oil and tallow (beef fat) have been used as feedstocks for the transesterification process.1 Today, the most common sources for biodiesel are: • plants:soybeans, peanuts, rapeseed, palm, corn, sorghum, canola, sunflower and cottonseed; • animal fats: tallow, white grease, poultry fats and fish oils; and • recycled greases: used cooking oils and restaurant frying oils.2 As the nation’s largest producer of biodiesel, Texas could benefit from any future expansion in its production or use. The biodiesel industry can affect the economy through investmentsin construction, spending on related goods and services and jobs.

EXHIBIT 14-1

Biodiesel Production Cycle
Sun Energy Crop Refining Food Products

Renewable Resources CO2 Biodiesel Production

Existing Technology Renewable Fuel
Source: PropelBiodiesel.

Glycerin Products

History
When German engineer Rudolph Diesel first demonstrated his compression ignition engine at the 1898 WorldExhibition in Paris, he used peanut oil for fuel. At the time, Diesel thought that biofueled engines were a good alternative to the steam engine. In fact, diesel engines generally ran on vegetable oils until the 1920s, when the engines were first altered to allow them to use petroleum products for fuel.3 Diesel was not alone in his faith in biofuels. Henry Ford designed his automobiles, beginningwith the 1908 Model T, to use ethanol, a fuel distilled from corn. Ford even built an ethanol plant in the Midwest and formed a partnership with Standard Oil to sell it in the company’s fuel stations.

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THE ENERGY REPORT

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MAY 2008

Texas Comptroller of Public Accounts

CHAPTER FOURTEEN

Biodiesel

New Sources for Biodiesel
Algae
Making biodiesel from little more thansunlight and water is an attractive proposition that at first may appear to be little more than science fiction. Nonetheless, researchers have been studying this approach since the late 1970s. Algae are single-celled organisms that, like plants, produce energy through the process of photosynthesis, converting water, sunlight and carbon dioxide into “food” in the form of an oil. This algae oil can beused to produce biodiesel for engines.4 Extracting the oil leaves behind dried green flakes that can be further reprocessed to create ethanol, another fuel.5 Algae intended for biodiesel are grown in water and fed carbon dioxide waste from industrial sources such as power plants, ethanol manufacturers, refineries and cement/kiln operations.6 The process can be used to reduce carbon dioxide emissionsfrom power plants, and the algae also devour other pollutants.7 Algae are highly flexible; they can be grown in most climates, and do not require arable land for production. According to the National Renewable Energy Laboratory (NREL), “[m]icroalgae systems use far less water than traditional oilseed crops.”8 Algae can be grown in brackish water, seawater and even wastewater. Algae are perhaps...