curtiss, thanks for all the intelligent questions. i learned a lot from watching this.

[…] am a little partial to algae myself, as can be intuited from my recent interview with Glen Kertz of Valcent, an innovative and promising algae biofuels company here in El Paso, […]

This algae to oil is very exciting stuff!! Great in-depth interview!! I have long dreamed of a viable alternative fuel - this look like one of the most promising out there. Well done guys!! Best Wishes. Tony McGinley. Ireland. http://wood-pellet-ireland.blogspot.com

Hi Again, My old brain works in a slightly rusty manner so it is slower to react than it used to be. There are a number of questions which spring to mind regarding the Vertigro operation.

There have been operational units in production now for perhaps 6 months or longer, long enough to have some sort of audit of the system. The question therefore are:

Q1. What is the actual consistant return of oil per acre of the units.
Q2. What are the total production cost per gallon.
Q3. What is the maintenance cost per acre per annum?
Q4 What is the actual audited percentage yield of oil form the raw algae.
Q5 How many more units have been built since the originals.

Regards,
Tony McGinley

I wonder how much energy is used to pump water through the system.

Perhaps my back of an envelope calculations are wrong, but 100,000 gal/ per acre/ per year seems implausible. The amount of energy that can be converted from sunlight into biomass is constrained by the limited amount of photosynthetically active radiation available and limits on the efficiency of photosynthesis itself.
Dimitrov, at the below address, has constructed a very cogent criticism of an algae photobioreactor company whose projections were for a more modest 11 gal/sq m/year. He concludes that even a tenth of that yield is a generous projection and that the cost of biodiesel so produced would top $800 a barrel.

http://www.nanostring.net/Algae/CaseStudy.pdf

The above post by matt newcomb misrepresents the information presented in the essay he cites. The essay examines the company GreenFuel and their proposed bioreactors hooked up to coal power plants.
The essay itself presents only one actual citation of a published paper and covers a swathe of topics, none very completely.

James Nogler,
Could you help us to understand the essay precisely?

I have read the Dimitrov’s essay and I am very interested in it.

Thanks

I’ve been very excited by the apparent potential of algae oil, too, and was even more excited to find Mr. Newcomb’s link to Dimitrov’s analysis; finally a careful analysis of whether this can work! I’m disappointed to say that his analysis holds up to all the checking I’ve done so far. I didn’t check the cost estimates, which seem plausible, but did an independent calculation of how much oil/acre/year could be grown under the best circumstances, to give some perspective to the wildly wide range of numbers I’ve seen. I came up with essentially the same amount as Dimitrov; ~4000 gal/acre/year. That’s much better than any other feedstock that I’ve heard of, but far less than many numbers bouncing through the internet (try Googling “algae oil gallons acre year”). Since 4000 is optimistic, I’ll be steering clear of any company that claims they can do better than that. I’ll also be looking only for companies that can achieve that number with cheap/low tech methods. I don’t see how anything in a greenhouse can do it. Solix might be onto something with huge, outdoor plastic bags, but I haven’t crunched any numbers for that yet. I’m keeping in mind too, that lower oil/biomass yields also reduces any carbon credit
income that may be used to argue for profitability.