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What are Biofuels?

Introduction

With prices for crude oil spiking in the recent past, and an unstable Middle East and intensifying effects of climate disruptions, the Obama administration and governments around the world have been promoting the development, and deployment of newer, more sustainable forms of energy generation, amongst which are biofuels.

What are Biofuels?


At the heart of every hydrocarbon based fuel (gasoline, diesel, kerosene, coal) are anaerobic degradation processes of organic material. For fossil fuels, the source of organic material comes from planctonic life, plants, and animals that lived and died millions of years ago. For biofuels, the source of organic material comes from planctonic life, plants or other sources of much more recent origin.

The important concepts to note are:

1.) Building up organic matter removes carbon dioxide from the atmosphere.
2.) Burning hydrocarbon based fuels releases the carbon originally tied up in the form of carbon dioxide.

So when we pump up the oil and burn it, we are releasing carbon dioxide that was removed from the atmosphere millions of years ago. The idea behind biofuels is that instead of releasing all the carbon dioxide stashed away millions of years ago, we become "carbon-neutral" by only relying on carbon sources that recently died to make gasoline.

Take corn for instance. When corn is growing, carbon dioxide is removed from the atmosphere as the plant incorporates the carbon into various cell components of the growing plant. Corn fermentation, the same process that also makes beer and fine wines, produces ethanol which can be used as a fuel to run cars. So when ethanol is burned in a car, the only carbon released into the atmosphere again in the form of carbon dioxide is the one that the plant absorbed before. Different plants can be used depending on climate and local geographical conditions. But the previous example, describe the basic idea behind the first generation biofuels. Theoretically, this describes a closed loop circuit which is close to carbon neutral because carbon dioxide released does not come from oil but from the plants we grew to make the fuel.

Disadvantages of First Generation Biofuels

In reality, however, especially corn-based ethanol has many problems. First, there are certain technical issues related to the inefficiencies of converting food crop into ethanol. Energy cost of production, and transportation of crops and fuel further reduce the theoretical yield and make these first generation biofuels less carbon neutral.

More importantly, there are concerns that high demand for energy crops could lead to increased deforestation because it may become more profitable to make more room for energy crops. Clearing of land for energy crops often happens in the form of burning forest land which releases more carbon dioxide than would be absorbed by growing just monocultures of corn. Scientist call this a "carbon debt".

Lastly, corn is also a food source for humans and other animals. Faced with limited arable land mass and water resources, increasing the demand for corn so that it can be used for fuel generation also increases the food price of these products. Because poor people can ill afford to pay more money for basic food sources, even small increases in the price can have devastating consequences on a families ability to buy basic sources of food in the third world.

Further research and careful policy making can potentially contain each of the above mentioned problems. In the next post, we shall look at the advantages one such approach and ask how algae can generally be used to solve some of the energy challenges we face today.

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