Like most of your fellow biofuel bloggers - you miss the central point regarding algae based biofuls - it's not the technology, it's the economics. You didn't provide one reference that show's even minimal information on the economic feasibility of algae production and more importantly the costs of processing algal lipids into usable biofuels. This is where everyone is struggling, current technologies are no where close to economic feasibility. In your defense, I have to admit that I know why you have no economic feasibility references. Curiously, there are no cuurent published economic analysis of algae biofuel production by any of the companies involved - at least I haven't found any. The reason is the primary product of the companies involved is not algae biofuel, it's either gov. grants or private investor money. When you start seeing the economics, you'll know that economic feasibility is now within the 50% probability range.

The economic factors involved in producing algae fuel as well as any other biomass derived fuel must take into consideration the expenditures of human life lost in the pursuit of secure oil sources (of course this is impossible, life is priceless), that portion of taxes paid in order to militarily support these endeavors of secure oil sources, the price on the environment and the economic impact global warming is having, and of course what price energy independence. But on a lighter note if we take the heterotrophically grown algae and feed it apple waste, farm waste , sugar cane stalk waste, etc. in fact any source of carbon that is already in a growth cycle we have no real feedstock cost input due to the fact that was WASTE to begin with. And as far as economically processing the algae, look up "Heichler" they make an ultrasonic processor which implodes the cell walls making the lipids readfily available. All this with no genetic modifications! Now if we begin treating algae as a food crop and begin genetically modifying it as say corn was in the past we can really get more for the money. All in all there are minor hurdles but this is the answer. Oh by the way, the dead algae can be distilled into ethanol. HMMMMMM!

I stand by my original response. Philosophically we might agree on the intangible costs of all fuels - and those costs also extend equally to alternative fuels, especially as our world population increases faster than our finite food production ability does.

However, your response only confirms my comments, as it provides not one quantitative piece of economic information on the net values of the waste products you reference. The economically efficient use of waste products has always been limited by their net value after considering the costs of gathering, processing and transporting them from their source to a centralized recovery/processing point. The waste items you mention are not new thoughts, anymore than is using algae to process them into salable energy.

It all comes down to real tangible costs (energy or financial). Waste product inputs have to out weigh their costs in the value the of their energy out puts under conditions of maximum competitiveness - in order to build a sustainable alternative energy industry around them. For example I am familiar with ultra-sonic cell fraction and to my knowledge no one has yet show its economic viability - probably because the electrical energy it takes to fracture the algae cells is not off set by its benefits, meaning it is too expensive to the entire process. Algae biofuel production isn't at commercialization point simply because it's economic feasibility in total has yet to be demonstrated or achieved - by anyone. Nothing more, nothing less.

Show me the hard economic (energy budgets and financial) analysis that proves you can produce a storable and salable algae biofuel for less than $2/gallon (easily accomplished by the petroleum industry competitors) and I would personally invest in that process - so would most other logical people.

Until we have a gov. that is serious enough in alternative energy development (and not in the pocket of BIG OIL) to level the economic playing field between alternative energy developers and the global petroleum industry we are at an impasse - until we physically run out of oil (not our past and currently manipulated marketing "oil crises.").

I welcome being proven wrong on this subject, but as yet no one has come forward with the kind of economics to prove me wrong. In the past few weeks we have had a 30%+ drop in crude prices. If this continues (as it has historically in the anthropic "oil crises" since the 1970s), it will only further diminish the economic feasibility of alternative fuel development including algae biofuels. So, please - if you're an algae biofuel developer, post your economics (not your proprietary technology) and show us that you have a credible and profitable algae fuel production process.