I grew up in the farm state of Iowa. Though I lived in the city, a short drive in any direction would put me in the midst of sprawling corn and soybean fields. At the time, nobody thought food crops might have potential for being an alternative fuel source. But when the Organization of Petroleum Exporting Countries (OPEC) hit us with the first oil embargo back in 1973, perceptions changed.
In 1980, I wrote a book on "How To Make Your Own Alcohol Fuels." At the time, everybody was gungho over ethanol alcohol as a way to reduce our dependence on foreign oil. There was a lot of buzz about energy independence, and a lot of people (farmers mostly) were investing in small scale alcohol fuel production facilities. Some of these were not much more than backyard moonshine stills, but others were modern facilities capable of producing thousands of gallons of fuel per month. Then oil prices came back down and the alcohol fuel movement collapsed, except for a few politically connected big time alcohol producers who got special tax breaks and incentives.
Fast forward to today. Oil prices are again being driven by politics in the Mideast. Ethanol alcohol is back again as both an octane booster and as an 85% ethanol/gasoline blend in "E85" for "flex fuel" vehicles. And now there's a new kid on the energy block called "biodiesel" vying for acceptance as an alternative renewable fuel to diesel fuel made from crude oil.
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, or less expensive animal fats such as beef tallow or chicken fat, or even recycled restaurant grease. Biodiesel can be blended with conventional diesel fuel much like ethanol is blended with gasoline. Most diesels 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. The most common blends include B2 (2% biodiesel), B5 (5% biodiesel) and B20 (20% biodiesel).
In 2016, biodiesel blends accounted for about 4% of total diesel consumption in the U.S. It is most commonly used in the Midwest. The total amount of biodiesel consumed was 2,189 million gallons.
The main advantages of biodiesel include:
* 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.
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.
According to industry sources back in 2007, biodiesel costs 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 remain in effect.
The production costs and the competitive advantage/disadvantage of biodiesel versus petroleum diesel can change quickly depending on crop prices and world oil prices. 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.
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!
By the end of 2013, biodiesel production hit 1.7 billion gallons, which is the third year in a row that biodiesel production has grown and surpassed the one billion gallon per year mark!. It is now over 2 billion gallons a year!
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.
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.
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.
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.