Pond Scum Refineries Revisited

Back at the end of December when we were just getting launched, I wrote an article entitled “Pond Scum Refineries” which dealt with the topic of algae as a feedstock for biofuel. The article was inspired by the buzz created by AlgoDyne, a startup with a lot of deep pocket investors and a lot of amazing claims for their technology.

In the article I went over some of the prior research on the topic and allowed that I was cautiously optimistic as to the potential of algae. I guess I still am to a certain extent, but now the caution outweighs the optimism by about a factor of ten.

One of the most depressing aspects of the whole alternative energy biz is the prevalence of gross misrepresentations and outright scams in what is simultaneously a business of idealists. Visionaries and dreamers are legion but so are the shady operators as well as those wishful thinkers who believe they will somehow get their technologies to work with just one more round of investment.

AlgoDyne and the seven or eight other algae startups out there may be legitimate and they may have something that will change the world. But don’t count on it. The past history of algae as fuel feedstock simply does not encourage this belief.

A Further Review of the Literature

Recently Biopact, a European bio-energy advocacy group, published a thirty-page account of the Department of Energy’s scientific investigation of algae and other aquatic species. There is also reference in the article to earlier research conducted in Japan. None of it is very encouraging. You can read the entire article at In Depth Look at Biofuels from Algae at Biopact.

For those who are disinclined to wade through several thousand words, I can summarize the more salient points here. Chief among them is the routine misrepresentation in the energy press as to algal yields.

I’ve seen estimates as high as 3,000 tons of biomass per acre cited in articles, including those in some academic journals. It turns out that no one has come close to that figure in any pilot program. The assumption behind the wildly optimistic estimates is that growth rates achieved in small closed containers will obtain in large industrial scale facilities, and that they may be achieved by constructing dense arrays of pipes, most likely constructed of glass or transparent plastic so as to admit solar radiation. Another proposal is to run fiber optic rods within the pipes so that sunlight could be radiated from the center as well as the periphery of the tubes.

The problems with these approaches are several. First, all that pipefitting is apt to be very expensive as will be the fiber optic splicing if one resorts to that. Furthermore, purpose built parts would almost certainly have to be used for most of the structural components. A multitude of small diameter pipes would also require extensive pumping facilities that would likely consume a great deal of electrical energy. Japanese investigations of such closed facilities were discouraging, and Japanese researchers quickly ruled them out as lacking cost effectiveness. Advances in manufacturing and a decline in materials cost especially in the case of optical fiber could warrant a re-examination of sealed cultivation systems, but the economics are uncertain to say the least.

If we turn to lower cost growing facilities, we find that figures in excess of 150 tons per frequently appear in journalistic discussions of algae farms, most of which consist of open channels of water excavated in fallow soil. But, here again, according to the D.O.E.’s work, nothing like that has been achieved in any large scale pilot. In fact, what invariably occurred in experiments where algae was raised in open vessels was that native species quickly overwhelmed the species selected as fuel feedstocks and total yields were far less than would be the case with quick growing tropical energy crops such as oil palm, jatropha, euphorbia, etc. Indeed, algae wasn’t even in the running.

Another partial misrepresentation frequently appearing in the press is an allusion to species of algae consisting of over 85% lipids by weight. Such lipids may serve as a feedstock for the production of biodiesel, and would be subject to an almost 100% utilization factor. Thus algae looks very good compared to the usual oilseed feedstocks where only a small fraction of the plant’s total biomass consists of useful fats.

The problem is that the species affording such high yields are not suitable in other respects, and those include the ease with which the plant may be harvested, its hardiness and growth rate, and its tolerance of cold.

The D.O.E study, which was concluded some nine years ago, suggested that selective breeding or genetic engineering could produce some kind of super-organism that met all criteria for an ideal feedstock, but so far no such organism has been developed.

I’m not necessarily ready to dismiss algae out of hand, however. The idea of putting the cultivation of the feedstock on an industrial footing rather than harvesting fuel crops from the soil strikes me as fundamentally the right approach in the longer term. And there’s no question that algae grow quickly and can be made to produce copious quantities of useful fats. It’s just that nobody has demonstrated industrial techniques to date that aren’t inordinately capital intensive.

In the future we’ll be examining all of the algae startups and perhaps issuing a special report on the topic if interest should prove sufficient. For now we are saying investors beware and look very closely at the economics of any purported breakthrough. Algae has gone through a number of hype cycles before and has never emerged as even a minority fuel feedstock. As they say, if something sounds too good to be true, it probably is.