Mr. Green Car has gone “green” with his recently-acquired Volkswagen Rabbit diesel. Not only does this car burn used cooking oil as a fuel, but the challenges of maintaining a 28-year-old cheap car are abundant, so I am sure this machine will be fodder for future writings.
This week, I’ll talk about what’s so green about using vegetable oil for fuel. First, it is not a fossil fuel. It’s not rotted old stuff from millions of years ago sold to us by people who don’t like us. It’s from plants that were basking in the sun not all that long ago, producing oxygen and burying climate-changing carbon dioxide.
The plants are harvested. The beans or seeds squeezed to release the oil, with little additional energy and no water needed. The oil drains away with nothing more to do than contain and transport it. The leftovers can be used as livestock feed or compost.
Although soybeans are commonly grown around here to produce oil, there are many other plants like rapeseed/canola and sunflower that produce much more oil per acre than soybeans. If the market forces priced plant-based oil at a higher value, agri-business would change what they grow to meet that demand. However, this switch in crops would take away from providing food from the same fields, driving up the price of dinner.
To avoid this conflict of fuel vs. food, researchers have shown vegetable oil can be produced from algae. The algae is grown in clear plastic bags in a sort of greenhouse environment where they can be milked of their oil, then sent back to rest and make more oil. This is a closed-loop system—sunlight, squeeze, use, make more—that can be established on almost any area exposed to sunlight. This would free the land for food, and make everything from rooftops to parking lots places where fuel could be grown. However, none of these algae fuel farms has been done on an industrial scale as of yet, but the promise is hopeful.
The algae farm is a much brighter source for fuel in our future than is field-based crops, as calculations show there is not enough arable land on the planet to satisfy our thirst for fuel. Fuel-efficient veggie diesel vehicles would drastically reduce our demands for foreign fossil fuels, but probably would not eliminate it. Presently, bio-diesel helps reduce this demand by cutting regular fossil fuel diesel with 2 to 20 percent vegetable (or animal fat) oil. Blended diesel is labeled B2 to B20, indicating the percent level of bio-sourced oil, and can be used in most diesel engines without modification. Straight (no fossil fuel) biodiesel, labeled B100, requires fuel system modifications.
Switching all vehicles to diesel/bio-diesel would radically reduce our demands for foreign oil and all the costs associated with those sources of fossil fuel. Europe already has a much larger fleet of diesel vehicles, owing to their decades of higher taxes on fuel, encouraging purchase of the most efficient vehicles. Europeans also grow more crops suited to producing oil.
About 3 billion gallons of waste cooking oil are produced annually in the U.S. Processing this oil as fuel would reduce fossil fuel use by only 1 percent; however, that also keeps these oils out of landfills and sewage treatment systems, and completes the carbon cycle of the plant by burning. According to the EPA’s Web site, http://www.epa.gov/region09/waste/biodiesel/questions.html, the following benefits to the atmosphere derive from use of biodiesel:
Compared to straight fossil fuel diesel…
• Acid rain-causing sulfates (SOx) are reduced 20 percent by B20 and 100 percent by B100.
• Airborne soot, particulate matter (PM) is reduced 10 percent by B20 and 50 percent by B100.
• Carbon monoxide (CO) is reduced 10 percent by B20 and 50 percent by B100.
• Smog-forming nitrogen oxides (NOx) are no different with B20 and increase 10 percent with B100 (NOx can be reduced substantially with catalytic converters).
• Most other air pollutants are reduced as well.
Additionally, B100 is carbon dioxide neutral and is non-toxic, less toxic than table salt, and biodegrades as fast as sugar. Personally, I’ve gotten my hands pretty messy with the veggie oil, and they feel nicer when I’m done cleaning up, whereas regular diesel stinks something awful and is hard to rid your hands of its smell—which is why you often see drivers wear gloves while pumping diesel.
When the supply of fossil oil runs thin, this environmentally-friendly fuel may be what motivates us. It does not need invention, just widespread implementation.
If you are really interested in bio fuel, a good book about the subject is From the Fryer to the Fuel Tank by Joshua Tickell.
from the July 29-August 4, 2009, issue