Comparison of Biofuels

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Taken from the SeattlePI, the full article can be found here

From the chart it becomes very apparent that not all biofuels are created equal, and that ethanol produced from corn doesn't seem to make much sense. True, it does give farmers in the Midwest another use of their industrial grade corn, but there is very little truth behind the idea ethanol from corn will break the American dependence of foreign oil anytime soon.

What appeals to me most about the table is the consideration of carbon dioxide emissions produced per megajoule of energy created. It allows for an objective look about the various biofuel strategies and their role as carbon sequestering techniques. Even after growing, harvesting, refining, and burning, biodiesel based on algae results in a net negative carbon dioxide balance. Furthermore, algae does not have to be grown on land that could be used for food production. Now if we could combine the algae blooms produced from nitrogen enriched agriculture runoff with algae based biodiesel production, we'd really be getting somewhere ...

Reactive Nitrogen Pollution

While a large focus has been placed on carbon dioxide emissions, articles published in Science by researchers at the International Nitrogen Initiative highlight another area of growing concern: reactive nitrogen pollution.

While 78% of the atmosphere is composed of nitrogen, reactive nitrogen refers to chemical compounds which contain nitrogen in a highly reactive state. Such compounds are found in the industrial fertilizers created by the Haber-Bosch process and nitrogen oxides produced by high temperature combustion of fossil fuels.

Reactive Nitrogen in fertilizers creates nitrogen enriched runoff, which triggers intense growth of algae once the runoff meets a larger body of water. As the algae in these blooms decompose, oxygen is striped from the water, reducing the water's ability to support life and creating 'dead zones.' (see NASA's images of the 5800 mile dead zone of the coast of Texas and Louisiana here)

It is estimated that 190 million tonnes of reactive nitrogen compounds are created per year, as well as 90-120 million tonnes of natural nitrogen compounds. While fertilizer is an integral component in the current methods of industrialized farming, an article in The Economist states that the reactive nitrogen derived compounds exhibit an uptake of only 10-15% in plants, with the rest of the compounds leaving the soil in the form of runoff.

There is definitely room for improvement in the area of plant uptake, as well as in the improvement of the availability of more natural forms of nitrogen. These improvements will help reduce these dead zones and improve the quality of our oceans and rivers while increasing overall agriculture yield.