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Algae-based transportation fuels

The urge to free the U.S. from its dependency upon foreign oil has resulted in some dramatic proposals, many of which are deeply entrenched in politics.

One such urge is to "drill, baby, drill", which means to allow oil companies to harvest U.S. oil reserves.  This makes sense if, 1) you hold stock in the oil company who might drill, and 2) you think that somehow local oil makes a local difference.  The latter is patently false, because the global oil market is 'on margin', meaning that all oil costs whatever the most needy party is willing to pay for a single barrel.  Non-renewable sources are not 'local' in any real sense.

Oil is primarily used for transportation.  What are the prospects for renewable transportation fuels?

One practice has been to subsidize the use of food crop plants to make bioethanol from sugars (e.g., corn) and biodiesel from fats (e.g., soy).  This practice has significantly raised global food prices, and diverted fresh water from its other uses.  Candidate non-crop macroflora such as switchgrass and poplar have their sugars bound up in a structural protein called lignan, which makes retrieval of sugars costly.

There is a solution, and the science is surging forward.  Microalgae under the right conditions can double their biomass in 24 hours, making sugars, fats, and proteins for a variety of uses, and are carbon-neutral because they ingest atmospheric CO2.  Saltwater microalgae can do their business in seawater.  It has been estimated that a land mass as small as Maryland near the Gulf of California could supply all of the U.S. transportation fuel needs, if an algae farm were placed there using seawater pumped in under its own power.  Various parties have their eyes on the Gobi and the Sahara deserts for the same purposes.

It may be time to start funding the right kind of energy.

The author's affiliation with The MITRE Corporation is provided for identification purposes only, and is not intended to convey or imply MITRE's concurrence with, or support for, the positions, opinions or viewpoints expressed by the author.