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Biodiesel vs Diesel

by Larry Carley copyright 2022-11-08

In recent years, an alternative fuel made from renewable resources has been taking market share from conventional diesel fuel. It is called BIODIESEL. The "bio" name indicates it is made from organic sources rather than crude oil. So how does Biodiesel compare to ordinary diesel fuel, and why has it gained so much market share in many areas of the country?

Biodiesel vs Diesel: What's the Difference?

Biodiesel is essentially diesel fuel made from renewable non-petroleum resources. Most biodiesel is currently made from soybean oil, but it can also be made from sunflower seed oil, algae, or even animal fats such as beef tallow or chicken fat. It can also be made from recycled restaurant cooking oil.

Biodiesel is typically blended with conventional diesel fuel much like ethanol is blended with gasoline. In theory, this helps to lower the price of the fuel and make us less dependent on the ups and downs of the world crude oil market.

Most diesel engines in late model vehicles can safely handle biodiesel/regular diesel mixtures of up to 10 to 15% with no modifications, and up to 100% straight biodiesel with minor modifications to the fuel system.

The most common blends include B2 (2% biodiesel), B5 (5% biodiesel) and B20 (20% biodiesel).

Biodiesel was introduced nearly 20 years ago in the U.S. Midwest as a home-grown alternative to petroleum-based diesel fuel. It's use grew quickly and by 2021, the U.S. was producing and consuming over 1.8 BILLION gallons of biodiesel annually according to the U.S. Energy Information Administration (EIA).

Advantages of Biodiesel vs Diesel

* It is a renewable resource that can be produced from a soybeans and other domestically grown crops or waste products, which reduces our dependence on foreign oil.

* It burns cleaner than conventional diesel , producing significantly lower particulate emissions and up to 78.5% less CO2 greenhouse gas emissions from production and use.

* Biodiesel provides better lubricity for injection pumps and fuel injectors. This helps extends engine life and reduces maintenance requirements.

* Biodiesel mixtures up to B20 require no engine modifications and are OEM-approved for use in most current diesel engines.

Are There Any Disadvantages of Using Biodiesel?

One of the concerns with B20 is that it may gel when temperatures drop below 40 degrees F (depending on the base stock), but the same is true of untreated conventional No. 2 diesel fuel. With the right additives (fuel supplement), B20 can perform just as well during cold winter weather as treated conventional No. 2 diesel fuel.

Some municipal bus fleets that use biodiesel run a 75% biodiesel mixture (B75) during the summer then switch to a treated 20% blend (B20) in the winter.

The Economics of Using Biodiesel

According to industry sources back in 2007, biodiesel cost about $1 a gallon more to produce than conventional diesel fuel when soybean oil is used as the primary ingredient. This makes the fuel about 10% more expensive than conventional diesel ($3.13 a gallon for biodiesel versus $2.70 a gallon for conventional diesel). To help biodiesel be economically competitive with conventional diesel fuel, it was given special state and federal tax breaks. In 2016, the federal tax breaks expired, but many state tax breaks continued to help make biodiesel cost competitive with diesel.

In July 2022, the average retail cost of B20 biodiesel in the U.S. rose to $4.80 per gallon versus $5.02 for petroleum-based diesel fuel.

The production costs and the competitive advantage/disadvantage of biodiesel versus petroleum diesel can change quickly depending on crop prices and world oil prices. The war in Ukraine in 2022 has sent world oil prices soaring and upset the normal pricing dynamics in all energy markets. Even so, today typically biodiesel tends to be competitive or even slightly less expensive to produce than conventional diesel. Consequently, many truck stops sell biodiesel blends because biodiesel is more profitable than straight diesel fuel.

Biodiesel Boom (and Bust)

According to the National Biodiesel Board, biodiesel production went from 25 million gallons in 2004 to 75 million gallons in 2005. For 2006, production increased to 200 million gallons! But then demand caused a significant drop in production during the financial crisis of 2010.

However, as the economy recovered, production went back up and continued to climb until today it is around 1.8 BILLION gallons per year in the U.S..

Municipal fleets across the country are using biodiesel in record amounts, and even the military is using biodiesel in its aircraft, ships and vehicles. Biodiesel is also available at most truck stops across the U.S.

Biodiesel makes economic, environmental and political sense as an alternative fuel, so the market should continue to grow. Some predict is use could grow to as much as 4 billion gallons/year in North America, 3 billion gallons in Asia, 2.5 billion gallons/year in South America, and close to 1 billions gallons/year in Europe.

Biodiesel From Other Sources

Nobody really questions the viability of biodiesel as an alternative fuel for diesel engines. But one concern is the Food versus Fuel issue. Some say we should not be using food crops to make motor fuel, and that the growing demand for renewable fuel has driven up crop prices, making life harder on the poor who can barely afford to eat now. The answer here is to make biodiesel out of feedstocks that are not food crops, such as algae. Various research and pilot production facilities are now making biodiesel out of wood fiber and algae. A company called Solazyme is producing biodiesel from algae on a commercial scale, and others are coming on line to compete in this growing market. A Canadian company called Cellufuel has developed a process for converting wood pulp into biofuel. With efforts like these, the issue of food versus fuel may become much less of an issue in the years ahead.

Volkswagen Completes Next-Generation Biodiesel Test

Back in June 2015, VW concluded a two-year trial evaluated the effects of renewable diesel with existing and next-generation TDI Clean Diesel applications. VW says it completed its Renewable Diesel Evaluation Program in collaboration with Solazyme, Inc. The tests found that every vehicle in the evaluation offered similar performance to existing TDI powertrains operating on today's crude-based clean diesel fuels.

The years earlier, Volkswagen measured the environmental impacts from the use of pre-commercial renewable diesel formulas with TDI Clean Diesel technology found in the 2012 Passat TDI (which uses a NOx storage system) and 2012 Jetta TDI (SCR system). Initial analysis found that advanced renewable fuels in the test offered comparable performance to standard crude-based diesel fuel blends while producing less CO2 emissions on average.

During the two-year evaluation, Solazyme's Soladiesel RD (100-percent algae-derived renewable diesel fuel) and the Amyris plant-sugar derived renewable diesel formula was used in 2012 Passat TDI and Jetta TDI models. Both fuel producers added additives, which are commonly used today, to meet ASTM D 975 specifications. With more than 134,000 miles logged collectively in real-world, on-road and on-highway conditions, Volkswagen engineers found the fuels did not negatively impact fuel economy. In fact, fuel economy was similar or improved.

In addition to comparable performance, greenhouse gas emissions (GHG) could be reduced by more than 50 percent on a well-to-wheel basis when using renewable fuels as compared to today's commercially available crude-based fuels.

Biodiesel Confirmed As Best Environmental Fuel

In September 2015, the California Air Resources Board (CARB) concluded biodiesel was the most environmentally-friendly alternative fuel for reducing carbon emissions. CARB's revised Low Carbon Fuels Standard says biodiesel reduces greenhouse gas emissions by at least 50 percent and often by as much as 81 percent versus petroleum. This gives biodiesel the best carbon score among all currently available liquid fuels.

"Biodiesel is the most sustainable fuel on the planet," said Don Scott, National Biodiesel Board director of sustainability. "Low carbon alternatives can also be low cost alternatives when we use diverse supplies of renewable resources. This validates that California's carbon reduction goals are obtainable."

As part of the state's low carbon fuel standard, the Air Resources Board has refined comprehensive lifecycle analysis to quantify the carbon intensity of conventional and alternative fuels. More than seven years of analysis have gone into addressing questions including indirect land use change. California's lifecycle model incorporates all the impacts for producing a fuel's raw materials including conversion and transportation. The model also includes the indirect economic impacts of growth in global agriculture-making it one of the most thorough and rigorous evaluations ever done to quantify the environmental footprint of biofuels.

The CARB findings echo what the U.S. EPA determined several years earlier when the EPA established the federal Renewable Fuel Standard (RFS). Under that program, biodiesel qualifies as an Advanced Biofuel, with the EPA analysis showing that it reduces carbon emissions from 57 percent to 86 percent.

"California's analysis, which has been validated by independent academic review, provides confidence that biodiesel is, without question, a more sustainable alternative for transportation fuel. The commercial success of the growing biodiesel industry suggests goals to further reduce greenhouse gases and displace imported petroleum are appropriate and achievable. With a focus on carbon reduction and the national policy to support it, biodiesel could reduce carbon emission by 40 million tons annually," said Scott.

The following is a comparison in grams of carbon dioxide equivalent per megajoule of fuel.

ULSD (standard diesel) 102.76 g/MJ
Gasoline 99 (CaRFG) g/MJ
Corn Ethanol 80.09 g/MJ
Compressed Natural Gas 79.46 g/MJ
Biodiesel made from soybeans 51.83 g/MJ
Biodiesel made from Used Cooking Oil 19.87 g/MJ
Biodiesel made from Tallow 32.83 g/MJ
Biodiesel made from Canola oil 50.23 g/MJ
Biodiesel made from Corn oil 28.68 g/MJ

Comparing these scores by the amount of each feedstock that is was used nationally in 2014 suggests that the average biodiesel in the market has a carbon intensity of 38.4 g/MJ. This gives biodiesel the lowest carbon intensity of any category of liquid or gaseous fuel. It also makes biodiesel competitive with electric vehicles as a carbon mitigation strategy.

Biodiesel Related Links:

Biofuels Digest

National Biodiesel Board

US Dept of Energy Biodiesel Information

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