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Webinar w/ Avigad Vonshak: Growth Rate and Productivity in Large Scale Algal Cultures
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Originally posted by clean and green:
By Avigad Vonshak, at Algae World 2008 Presentation

27-minute video by a thirty year algae industry veteran, who explains the potential pitfalls facing commercial-scale algae farming for biofuel production.

You can download the original video, in two parts totaling 27 minutes, which plays in Windows Media here:
http://www.futureenergyevents....deo/vidHZ527KMV.html

Also in Algae Video list.

This message has been edited. Last edited by: clean and green,
 
Location: Green Bay, WI | Registered: June 26, 2004Reply With QuoteReport This Post
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Part 1 - "This video is brought to you by the Center for Management Technology - Organizers of the Algae World Conference."

(Americanized for easy reading)

Avigad Vonshak-
-Ladies and Gentlemen, thank you for giving me the opportunity to share with you some of our work and my personal thoughts about the potential of micro-algal biotechnology to be used as a source for renewable energy. Being involved in the micro-algae industry for 30 years, some people would say I have seen it all, coming up and coming down. What we have to remember is that when we oversell, we basically damage the concept. And this is why I've decided to bring to mind this gentleman (Shakespeare) who put the following words into the mouth of Antonius: I come to bury Caesar, not to praise him.

And if I may rephrase what he said, I want to say to you, friends and phycologists, we have to stick to the facts. We have to understand, where are the limitations of algae? And make sure that if, after 3, 4 years from now, I see you in another place, and I say I'm coming to bury micro-algae for biodiesel, it will at least be based on real facts, and not the fiction.

And the fiction comes with the fact that many people are taking part of the information, the part that is very convenient for them, in order to fulfill different purposes, and then extrapolating it in a way that is not necessarily what we in the R&D and the scientific arena believe.

(2:05) - "Algae are the fastest growing organisms on the planet"

First of all, this is a very common statement that you can find on the internet on a daily basis. Unfortunately it is not true. Many other microorganisms grow much faster. This is something that we have to remember. What is true is that micro-algae grow very fast. Some of them. Some Some of them have a doubling time of about 180 minutes, or what we call a generation time of about 3 hours. But, what we have to remember is that fast growth rates are not necessarily associated with high productivity.

Y = u - X
(Specific rate = u
Biomass concentration = X)

We have to remember that productivity is a function that combines two factors: the specific growth rate and the biomass concentration. And as a result, we actually achieve the best productivity not necessarily at the highest growth rate .

(3:10) What you see here is a set of experiments that was conducted. Each of those points (on chart) is a culture that was maintained for at least one month, harvested on a daily basis to maintain the biomass concentration constant, and measured by optical density. And we have measured and knew the specific growth rate. And you can see that one can get very high specific growth rate. In this case, in the summer it is the highest. The reason it is highest in the summer, in this case the culture is cultures of spirulina which is at an optimum of 30-35 degrees C (86-95 F).

And as you increase biomass concentration you decrease specific growth rate. This is for an obvious reason: the higher the density of the biomass, the less light that is coming in. This is a well mixed open pond, and yet the higher the biomass, the lower the growth rate. And basically you can grow here, (on chart) on this scale this would be low light intensity (left side), this would be very high light intensity (right).

What we have to remember is that we don't necessarily have to be impressed by the fast growth rate. What we are after is the productivity. Area productivity, volumetric productivity, choose whatever you want. But choose units that you are measuring, and not those that you are extrapolating.

(5:00) And then you can see that the maximum productivity is achieved at what we call the 'Optimal Biomass Concentration' (classic bell curve) In other places it would be called the Optimal Area Density. But this is where we are getting our highest productivity. Why is this important? It is important because we are not looking for a fast growing cell. We are looking for a cell that can utilize light in an efficient way, in the limited region of photosynthesis. And I'll go later on into some of the implications when we do strain selection. But this is something that has to be clear when we are evaluating some of the numbers that you see here:

(5:50)

Oil yields_________liters/ha year_____barrels/ha year
Soybeans____________400___________2.5
Sunflower____________800___________5
Canola______________1600__________10
Jatropha____________2000__________36
Microalgae_____60,000-240,000____360-1500

And the problem is that, when we deal with higher plants like soybean, canola, you name it, we have concrete data and very defined numbers. When we get to algae, it is really predictions. And some of them exceed the maximum theoretical photosynthetic efficiency. And believe me, in order to make micro-algae for biomass, for biodiesel, feasible, we have to explore the potential without breaking the laws of thermodynamics.

(6:40 - current production chart)
And this is the reality. It's not encouraging, but it's not surprising. Because every time there is a boom, people are rushing into micro-algae. And when the oil prices are going down like what happened in the last month, I'll not be surprised if this is the last meeting on biodiesel from microalgae, while waiting for another 5 years till the price is going up.

I've tried to look at some of the literature and compare some of the data, and I gave up. And the reason was because of the units!
(7:20) hectares-acres-long tons-short tons-metric tons-barrels-US gallons-Imperial gallons...

Now this is just an example of what I'm seeing in the literature. And believe me, I had to go into different engineering textbooks in order to find all the conversion factors. Finally I gave up and left with the impression that the people that are using those units are using it in order to get me confused. Or maybe the investors.

(7:50) You may think big but please use small words - units. What's wrong with g/sq. meter per day?

So please, whatever your predictions are, whatever you extrapolations are, start with the numbers that you measure. And eventually you are measuring grams per liters per square meter, whatever, per day. Then you multiply by whatever you want, but at least let us understand, what is your starting point?

(8:30) Algae are specially adapted for photosynthesis

This is another claim that you keep on seeing in the literature and on the internet. Unfortunately this is also not true. The photosynthetic apparatus evolved during years of evolution, and it's a very rigid and a very conservative system. Photosynthetic driven CO2 fixation, splitting a molecule of water is very similar in many of the photosynthetic organisms. The advantage of micro-algae is that we are using most of the biomass, as compared to, let's say, jatropha, where in order to make up our oil we need, we use only the seeds.

But, we have to realize that utilization of light is a very sophisticated process. And, if you want, also a very dangerous one, because we are dealing with energy. And in many cases the question comes, do we really have enough light? Or maybe we have too much light? And it's like having too much of a good thing.

(9:30) Light Usage Chart
Whatever you're measuring, immediately you will realize that basically we are using in the photosynthetic process only part, and a very small part, of the total solar radiation. You will see different figures describing the absorbed light, the photosynthetic power as a function of total absorbed, utilized, wasted, etc. terminologies.

(10:00) This is a classical, what we call a P.I. curve, a light response curve that you will find in any textbook describing photosynthesis. And there are basically few parts in this figure. The one which is identified is the Initial Slope, and I call to your attention that plants and algae are not only devolving oxygen, but also utilizing it. They respire in the dark. And when you grow algae outdoors remember that there are in a day 12 hours of light if you are lucky, and also 12 hours of dark. And during those 12 hours the algae and plants do respiration.

This message has been edited. Last edited by: clean and green,
 
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Part 2

And then we have the Initial Slope, which is also helping us to calculate what is defined as the quantum yield of photosynthesis, namely how much quanta of light are required in order to fix a mole of carbon, or to evolve a mole of oxygen. And then there is the P max, the maximum capacity of photosynthesis, and at very high light intensities this is what is written in the book. There is also photo-inhibition.

Unfortunately, we know today that photoinhibition may take place not only at high light, but also at low light. Photoinhibition is the result of the inability of the plant or an algae to utilize an excess of energy. People will define it not only as photoinhibition but also as downregulation. In both cases it means that the apparatus is not functioning at its maximum capacity. And basically the curve will look like this, if you are lucky. And the only things that change is the quantum yield. In many cases it will also affect the P max. Basically what you have to remember, regardless what is your growing system, open ponds, tubular reactors, hanging sleeves, lying sleeves, inclined photobioreactors, your biomass is very dense. Your culture is light-limited. You are really far away from P max . And what you do is you operate your system at light-limited conditions. This is imposing a major problem that can be overcome, and can be optimized, if you know that you have a problem. And some people really ignore it.

(2:10) I've tried to look into the literature about different numbers of photosynthetic efficiency, and I picked the most optimistic one, and believe me it's the most optimistic one. This is courtesy of professor Stephen Long from (Ohana?) who is now heading one of the large projects of biodiesel, the $500m British Petroleum project in the U.S. And he was really very generous. If you look at the other numbers, the efficiency will go to 4%, 4.5%. But this is the maximum.

(3:00) Unfortunately, when you look into reality, the top numbers that we get with higher plants at the best conditions is 2.5%, and the average is much lower. So the higher- plant people claim that they still have an additional card up their sleeve which is called the C4 plants, which can have a higher efficiency due to the ability to concentrate CO2, but this comes at the expense of extra investment in energy.

(3:40) So if we really want to improve our photosynthetic capacity, there are basically two approaches: one, to maximize the photosynthetic capacity, and the other one, to try and avoid and minimize the reduction due to stress conditions.

(4:00) Basically, as this cartoon describes, we are either trying to lift the ceiling, or to improve our photosynthetic efficiency.

(4:10) Here's an experiment that demonstrates the problem. We are all educated to believe that the more light, the higher the productivity. So this is summing up a whole year of experiments done in the desert, with spirulina. An open culture, grown in summer, at high level of temperature. The productivity was about 20 grams per sq. meter per day. If we took the culture and we shaded it by a method that reduces 25% of the total light, the (result) is that we actually increase the productivity, contradicting all of the expectations. When we took the culture, and we've put it into a greenhouse, which reduced the light intensity, but elevated the temperature, in summertime, when temperature is not supposed to be a limiting factor, we actually improved further our productivity.

(5:30) So we said let's measure what happens in the pond in terms of photosynthetic activity. So we are doing two cultures: an unshaded one, the blue line, and a shaded one, the red line, measuring photosynthesis in the pond, online during the day. For the first two hours, everything goes fine: more light, more photosynthesis. This (chart) is going from 6 in the morning till about 10. And the shaded culture has a lower photosynthetic activity. But, at a certain stage, suddenly something goes wrong. In the unshaded culture, as photosynthesis drops, while the shaded culture keeps on growing. This phenomenon of decrease in photosynthetic activity during the day is a very known phenomenon in higher plants, "midday repression". Explained by the fact that stomata are closed, and there is a depletion of the regional concentrations of CO2. Unfortunately, this can not be an explanation for a spirulina pond. They don't have stomata, and they have CO2 as much as they want.

(7:00) So what went wrong? Let me remind you again, in photosynthesis, light is exciting a molecule of chlorophyll, that can be used in the photosynthetic apparatus, to advance photosynthesis, this is what we call the photochemical quenching. Excess of energy that is absorbed has to be taken care of by different protective mechanisms, otherwise it is causing damage.

(7:30) And this damage can be measured, and I will not go into the details, can be measured by measuring the very simple parameters of variable fluorescence which is called Fv over Fm, and it is measuring the maximum photochemical capacity of the plant. Not the actual productivity, not the actual activity, but the potential. But what you can see in this figure, that measured Fv/Fm in those 3 cultures I previously described, is that as soon as we have sunrise we have a decline in the potential.

Why is it? Because we are causing stress conditions. Not because of too much light, of high light intensity, but because of the conditions. Those of you who live in the desert know that it's very hot during the day, but it can be very cold during the night. And this is basically what happens.

(8:30) And a problem that people are not talking about, is oxygen concentration. In open ponds, it is easy to handle. In closed systems, it gets to be a problem. And parameters like flow rate, diameter of the pond, of the pipe, are the ones that are going to define whether your productivity is going to be high or low.

(9:00) Now this is not an invention. This is basically a result of the fact that RuBisCO, the major enzyme that is responsible for CO2 fixation, is an inefficient enzyme. The plant is making lots of it, and knows how to use it in order to fix CO2. But, under low CO2 concentrations, and high oxygen concentration, it goes wrong. It goes wrong, it means that it's not fixing carbon anymore.

(9:30) And as a result, you can lose almost 50% of your potential. Or, if you want, if you remove oxygen, you can increase productivity by almost 100%.

(9:50) As I said, the cultures are light limited. There's a problem of having huge antenna size. I will not go into it, there's a lot of examples in the literature, where you can actually isolate strains with a lower antenna size. But what I want to do is to share with you some new data coming out of my laboratory.

(10:15) This is D1, a protein part of photosystem II known also as the herbicide binding protein, one of the most important proteins in the photosynthetic apparatus. People are trying to mutagenize it, genetically engineer it. The problem is, that most of the mutants that are being produced grow at a lower rate, and having a lower light intensity. We decided not to use genetically engineering methods. First of all, because the algae that we use is porphyridium, a very difficult one to get cloning into because of the polysaccharides, but a very interesting one because it has a huge antenna and accumulates at the essence.

We isolated a mutant that under normal conditions grows the same as the wild one. But, if you increase the level of salinity, and this is on top of the sea water, an additional 1 mole of sodium chloride, you can see the difference. The wild type is significantly inhibited as compared to the mutant. If you expose the cells to high light, and measure the damage, you can see that the mutant is much more resistant.

(11:45) If you now check the levels of the D1 protein, you can see that the mutant has the ability to maintain the D1 level at a much higher level. And this is the kind of thing that we still are missing when we are doing our attempt to go to this stage.

(12:05) Now you will hear many stories of why this is a story of success. I want to refer to the ones that say there is no contamination. There is. No one will tell you about it. Spirulina - this organism has e-coli(?) living on it.

(12:25) Dunaliella, e coli(?) is eaten by this one. Even in photobioreactors, in closed systems where people will tell you that porphyridium is a very tough organism and there is no contamination, believe me, there is. It sucks it in, and it gets all of it out. And you can come, and within a day, the only thing that is left are empty cells.

(13:00) And to scale up is another challenge. This is one of the first photobioreactors developed in France by Claude Guden(?)

(13:10) It was never able to scale up because it could not get as big because of oxygen problems. The breakthrough came when instead of having just pipes running back and forth, we introduced this simple device known as the manifold.

(13:25) And this is what enabled us to go bigger, not only in Israel, but also in Italy, and this is another site where you have today photobioreactors. And those were true photobioreactors that are still in function. But this is a story that has to be told, because this is one of the first commercial photobioreactor systems in Spain, and this one

(13:55) is just PhotoShop. And this is the easy way of scaling up.

(14:00) Also this one. So there is no difference between big ponds or photobioreactors because this is the reality. And you have to maintain the right scale.

(14:10) This is how it looks in terms of agriculture.

(14:20) So this is the site, and this is how it looks for only two weeks. After two weeks,

(14:25) This is what is left. And if you write a book, 'What can go wrong in a photobioreactor system', you can get quite a lot of money out of it.

So can algae save the world? I don't know. Will we be able to drive

(14:45) this car? Maybe. We are allowed to dream. But if we want to get there, we have to do much more work. And the work starts with reading what was already done. John(?) said there is enough information, and the problem is that people are not reading it. Please don't reinvent the bicycle, otherwise the only way to produce energy would be from

(15:15) this way. Thank you very much.

(end of presentation)

This message has been edited. Last edited by: clean and green,
 
Location: Green Bay, WI | Registered: June 26, 2004Reply With QuoteReport This Post
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Links to follow-up information


News and Views www.dailypaul.com
 
Location: Green Bay, WI | Registered: June 26, 2004Reply With QuoteReport This Post
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this seemed like the best place to post this hypothetical according to title heading. - WHAT IF

instead of converting algae lipids directly to fuel he/she used the 100+ tons/year/acre to feed 50 tons of pacific oysters (s.gigas) or 60 tons of tampa bay mussels(p.viridis) - then buried the harvest into the ground for a later(much) recovery of fossil fuel? would this save the planet? to me it seems as a slightly better alternative than purchasing fifty or so $800 dollar algae to bio diesel(feedstock) plants - even considering prices over $50.00 /gallon for diesel.
 
Registered: April 26, 2005Reply With QuoteReport This Post
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Actually a better idea would be to bake a whole bunch of bread and bury it in a secret location, making sure to create a map of course, so future generations could find the bread and sell it on the market, since history tells us that the price of bread usually trends upwards...


News and Views www.dailypaul.com
 
Location: Green Bay, WI | Registered: June 26, 2004Reply With QuoteReport This Post
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quote:
Originally posted by clean and green:
By Avigad Vonshak, at Algae World 2008 Presentation

27-minute video by a thirty year algae industry veteran, who explains the potential pitfalls facing commercial-scale algae farming for biofuel production.

You can download the original video, in two parts totaling 27 minutes, which plays in Windows Media here:
http://www.futureenergyevents....deo/vidHZ527KMV.html

Also in Algae Video list.


News and Views www.dailypaul.com
 
Location: Green Bay, WI | Registered: June 26, 2004Reply With QuoteReport This Post
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Other Webinars:

Avigad Vonshak at Algae World 2008 Presentation

"27-minute video by a thirty year algae industry veteran, who explains the potential pitfalls facing commercial-scale algae farming for biofuel production..."

http://biodiesel.infopop.cc/ev...01000031/m/421103531

Webinar - Utility Scale Algal-Based Carbon Capture with Jim Sears of A2BE

"Jim Sears is the Chief Technology Officer for A2BE Carbon Capture and the chairman of the Technical Standards Committee for the Algal Biomass Organization. He has been a thought leader and organizer for the unfolding algal industry since the year 2005..."

http://biodiesel.infopop.cc/ev...01000031/m/643100301

Webinar w/ Carel Callenbach and Marc Van Aken: Algae Opportunities

"Hello everyone and welcome to the Algae Opportunities Production Challenges & Applications Webinar. We are presenting this webinar in line with Algae World 2009's commitment towards sharing a realistic snapshot of where the algae industry is today..."

http://biodiesel.infopop.cc/ev...01000031/m/180108221

Algae Realities from the Guy who Wrote the Book - John Benemann

http://biodiesel.infopop.cc/ev...01000031/m/908105151

This message has been edited. Last edited by: clean and green,


News and Views www.dailypaul.com
 
Location: Green Bay, WI | Registered: June 26, 2004Reply With QuoteReport This Post
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