biofuel basics

Curious about biofuels? The newly pumped up environment section has a great primer, here’s a sample:

A Spectrum of Biofuels

Biogas

Organic materials such as dung and agricultural waste can easily be treated in biogas plants to produce energy (biogas) and fertilizer (slurry).  Biogas is generated if organic materials are allowed to rot in closed, airless tanks at suitable temperatures (20-40°C).  This is ideal for Equatorial areas.  The process is called “anaerobic digestion”.  Bacteria convert the organic matter into combustible biogas (methane, carbon dioxide) and fertilizer (ammonia).

Ethanol

Ethanol (ethyl alcohol) is the same type of alcohol found in alcoholic beverages.  It can be used as a fuel, mainly as an alternative to gasoline, and is widely used in cars in Brazil.  Because it is cheap, easy to manufacture and process, and can be made from very common materials, such as corn, it is steadily becoming a highly respected and researched alternative to gasoline throughout much of the world.

Butanol

Butanol may be used as a fuel in an internal combustion engine.  Because of its long hydrocarbon chains cause it to be fairly nonpolar, it is more similar to gasoline than ethanol.  Butanol has been demonstrated to work in some vehicles designed for use with gasoline without any modification.  It can be produced from biomass as well as fossil fuels.  Some call this biofuel biobutanol to reflect its origin, although it has the same chemical properties as butanol produced from petroleum.

Biodiesel

Biodiesel (methyl esters) refers to a diesel-equivalent processed fuel derived from biological sources (such as vegetable oils) which can be used in unmodified diesel-engine vehicles.  It is thus distinguished from the straight vegetable oils (SVO) or waste vegetable oils (WVO) used as fuels in some diesel vehicles.  Biodiesel is biodegradable and non-toxic, and typically produces about 60% less net carbon dioxide emissions than petroleum-based diesel, as it is itself produced from atmospheric carbon dioxide via photosynthesis in plants.

Biofuels provide sustainable alternatives to fossil fuels, harnessing one renewable source of power – today’s living plants.  Unlike petroleum fuels, which require millions of years before the conversion process is complete, the use of biomass can be planned for and replaced relatively quickly.  Biodiesel is one alternative fuel that is a safer and cleaner burning fuel.  The use of biodiesel and other alternative, biomass based fuels can help us remove ourselves from dependence on others and the political complications found in today’s global economy.

Straight Vegetable Oil (SVO) and Waste Vegetable Oil (WVO)

Many vegetable oils have similar fuel properties to diesel fuel, except for higher viscosity and lower oxidative stability.  If these differences can be overcome, vegetable oil may substitute for #2 Diesel fuel, most significantly as engine fuel or home heating oil.  For engines designed to burn #2 diesel fuel, the viscosity of vegetable oil must be lowered to allow for proper atomization of the fuel, otherwise incomplete combustion and carbon build up will ultimately damage the engine.  Many enthusiasts refer to vegetable oil used as fuel as waste vegetable oil (WVO) if it is oil that was discarded from a restaurant or straight vegetable oil (SVO) to distinguish it from Biodiesel.

Want more?  Click here for the whole thing and nice job Mr. Blue, Alex, and PQ getting this info out there!

About the author: Tom Price

Tom Price

Tom Price is the former Executive Director of Black Rock Solar. Prior to that he was the Environmental Manager for Burning Man during the Green Man theme, and was in the Gulf Coast for six months during the genesis of Burners Without Borders. He's been attending Burning Man since 1997, and he's proud to say that his decade plus streak of breaking down from sun stroke on the playa on day three remains intact.