In 2000, the Department of Energy estimated that it would take 15,000 square miles to replace all petroleum fuels with algal fuel. Now this is about the size of Maryland, which may sound shocking, but it is only about 1/7 of the land that we currently use to grow corn.
Of course, this study didn't take into account factors such electric cars, other biofuels, efficiency, public transportation, possible changes in miles driven per person-year, population and so on. So it must be taken as one basic reference point, rather than final word. But basically it makes the idea that algal fuel could have a strong role in dealing with oil shortages, global climate change, and the consequences of oil geopolitics, look challenging but plausible.
Of course, it is well known that problems exist involving factors such as costs, and the technological hurdles of extracting the algae from the water and the oil from the algae. However, I was appalled if not horrified at the "solution" proposed by LiveFuels. Namely to feed the algae to fish and since the technology for extracting oil from fish is no different from extracting it from a whale, use fish oil as a biofuel!!
Already the idea that the technology has been around for over a century, has been used to support another turkey of an alternative fuel, specifically corn ethanol. Both seem to involve cases of choosing a fuel that will likely have limited supply and bad numbers as far ecological impact, water use, and EROI (Energy Return on Investment), simply because "the technology is not complicated". Corn ethanol is basically a lousy investment in that it uses a huge amount of water and only provides 30% more energy than is required to produce it.
Fish oil biofuel is a similarly grim prospect. I question whether or not it is ethical to raise and kill such a massive number of animals-even if they are "mere" fish-not for food or sustenance, not for medicine, not for scientific advancement, not for ecological restoration, and not even to feed our pets, but simply to run combustion engines. On a more utilitarian note, it promises to be extremely inefficient. The most basic reason is one can expect it to take at least ten units of algal biomass to produce 1 unit fish biomass, as a basic principle of ecology. So if the theoreticaly amount of algae oil we would need to replace petroleum entirely would be 1/7 the amount of land we use to grow corn that sound difficult but manageable. However, if you multiple the amount of algae and therefore the amount of land by tenfold than it would require more land than we use to grow corn, in order to produce the same amount of fish oil. And of course that's also ten times the water demand (even if much of it could theoretically be sewage or saltwater), and ten times the energy required to grow the fish, before killing them and extracting oil from them.
Certainly there is no doubt that learning how to make harvest oil from algae efficient and cost effective is going to take a lot of work. However the advantages of algae include it's ability to grow rapidly with minimal inputs. Fish do not have that advantage even when fed fast growing algae.
As with the choice between corn ethanol versus bioforming waste cellulose int various fuels, and the choice to pursue carbon recycling or underground sequestration, the bottom line is whether you will accept limited supplies and low ecological efficiencies in return for a simpler technologies, or whether more effective solutions are worth investing time, research money, government support (of which petroleum gets plenty), and above all changes in the status quo and the way things are usually done. The former is the sort of conservative solution that demands little but provides little in return. The latter are solutions that demand a lot, but deliver the good. In this vein the "dividends" for photovoltaic research are just being to come in, and wind energy is finally hitting it's stride.
With research the same is likely to be true with actual-fish free-algae products.
Say Goodnight Readers!
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