This is the third post in a series of blogs titled ‘Bottlenecks, Trafficbocks and Deadends’ intended to address Algae Commercialization barriers.
Please check out for my previous posts at: http://www.oilgae.com/club/users/Gopinelli/blogs/1207 (Bottlenecks, Trafficbocks and Deadends)
Cell Cycle Management
In natural day-night conditions many algae species complete one cell cycle per day. In many such colonies exponential growth is observed during early hours of the light period, which is followed by a decline in growth rate. Similarly, maximum cell division is observed during early hours of dark period. This indicates that actual cell cycle duration of the species is less than one day.
Dark and light periods longer than actual cell cycle duration of the species have the following impacts:
- The colony consumes maximum carbon dioxide during exponential growth and carbon consumption declines as growth rate declines. In the absence of continuous growth monitoring and carbon dioxide dispensing accorgingly, achievement of projected carbon mitigation is difficult. Expulsion of unutilized carbon dioxide through the media will also increse system footprint.
- Day-night cycles longer than actual cell cycle of the species causes cells medtabolize on cell matter, affecting energy efficiency of the system.
- Longer exposures can increase chances of photo-inhibition, fouling and culture collapse.
In fact, cell cycle duration of algae vary from species to species. There are some algae strains available with depositories that can, all growth conditions provided at optimum levels, complete one cell division during every 90 minutes. The major issue with this species is exposing the strain to alternate dark and light periods of appropriate durations (that is one dark period and one light period during every 90 minutes). Theoretically this species can undergo 16 cell cycles per day, under night time artificial lighting and multiply biomass nearly 64,000 times within 24 hours. At a very conservative 10 cell cycles per day, 1000 fold biomass multiplication is possible.
But, how can it be achieved?
First, you need to synchronize the metabolic activity of the colony to maintain majority of the cells in same growth phase.
Then, introduce the synchronized colony to alternate dark and light periods, maintaining active light period 24/7.
A practical approach is continuously introducing a lab-synchronized colony to a closed loop bioreactor system capable to provide alternate dark and light periods and provide artificial lights during night and low light hours. Dark chamber and light chamber of a bioreactor in the system bioreactor system should have a volume proportion corresponding to the proportion of actual dark and light period of the species. Media flow rate is to be adjusted in such a way that the colony stays in the dark chamber at least for a duration corresponding to the dark period of the species and in the light chamber at least for a duration corresponding to the light period.
Short cell cycle and artificial lighting during night has the following advantages:
- Reduce crop period, several fold improvement in biomass yield.
- Round-the-clock carbon consumption at consistent rate.
- Improves System energy efficiency.
- Minimizes risks of photo-inhibition, and culture collapse.
My closed loop continuous flow bioreactor system features the capability to provide alternate dark and light periods corrensponding to actual cell cycle duration of the colony, continuously, under night time artificial lighting. The system can be adjusted to match any cell cycle duration and any micro algae species.
*** Please check out for my upcoming blog post in the series- Be a Farmer
This is part of an upcoming series of blogs titled ‘Bottlenecks, Trafficbocks and Deadends’ intended to address Algae Commercialization barriers.
Please check out for my introductory post at: http://www.oilgae.com/club/users/Gopinelli/blogs/1207
For an algae system, scaling up is the most important and complex commercialization barrier. There are lot of issues to be addressed for successful scale up of a bioreactor system.
In nature, open ponds are capable to provide proper light exposure to dense algae colonies at 10-15 cm depth. Such a culture usually yield 2-3 g/liter dry biomass. Thus, an open pond can contain upto 600 m3 media per acre. In raceway ponds, media volume is usually around 400 M3/acre. A bioreactor should considerably improve media holding capacity in order to justify high equipment cost. But, media capacity per acre of those bioreactors available today are not known.
Simply put, scaling up of a bioreactor means impropving both reactor volume and light penetration. Improving volume is no big deal. But, the problem lies in light exposure. Improving surface of light exposure by modifying shape of the container is one means to improve light exposure. Trying this usually take you to the dead ends.
You may consider a vertical tubular bioreactor because of the structural strength of the shape and that it allows light penetration from all around. But immediately you find that diameter of the tube can’t be increased beyond a limit for self shading of alge cells develop an internal dark region where the cells are unable to perform photosynthesis.
Vertivcal bioreactors deployed closely to one another shade each other. So you are forced to deploy the bioreactors spaced far apart from one another. You may consider increading height of the bireactors, But you find shading also inceasing in rproportion to increasing height, increasing the spacing of deployment. Further more, you need structural elements to support the tubes, inviting additional elements that shade the field. Finalky you end up with heavy imvestment, but no volume advantage.
You may consider modifying the shape in different ways. But, to your disappointment, the final outcome turns around to be the same. Now you understand the conservative nature of THE NATURE. And your only option is going back to open ponds and blogging on scaling up issues. Your fellow bloggers hail your language skills and that’s the desperate end of a “research”.
Let us look at the scenario in a different perspecive.
Light and shade are complementary to each other as night and day are. Shade occurs because there is light. Light causes earth shade, like any opaque object. Sun continuously illuminates one side of the earth causing the earth shade itself on the other side. Axial revolution causes alternation of light and shade in defenite pattern with reference to a particular pint on earth’s surface, causing the day-night transition. In nature, day and night are in perfect equilibrium in an ecosystem perspective. Life on the planet is adapted to this natural day-night transition.
Man has already manipulated natural phenomina, environmental elements, and even genetic sequences of organisms to make certain organisms work the way he wants.
Algae cells do shade under light, And closely deployed bioreactors shade each other too. And we know, algae need light to perform photosynthesis, while they do not need light for cell division..
Now, lets look at a large volume photo bioreactor, A part of a dense algae colony contained within the reactor should be receiving enough light to perform active photosynthesis while light penetration gradually declines until formation of a totally dark intedrnal region.
Here are my questions:
Can’t we isolate the outer illuminated region from the inner dark region?
Cant we expose a fully grown mature colony to the dark region so that the cells will divide in dark, while simultaneously allowing a young colony to perform photosynthesis and grow in the illuminated region?
A large volume bioreactor means more media volume per bioreactor. Isolating the inner shaded region from an outer dark region provides more flexibility to bioreactor size and thereby volume of the illuminated region.
But how can you effectively expose a part of a colony to light and another part of the colony to dark in the same bioreactor at the same time?
Like large plants, an algae colony comprises cells in various growth phases. But the colony can be synchronized to maintain cells in the colony in same metabolic state. Entire volume of the bioreactor can be effectively utilixed by exposing a young synchronized colony to the light region of the bioreactor and a mature synchronized colony to the dark period. Efficiency can further be improved by exposing the same colony alternatively to dark and light at a media flow rate regulated to match durations of dark period and light period of the cell cycle of the species.
Now, you are certain to encounter with the next issue. You need to deploy bioreactors spaced far apart from one another in the field to overcome mutual shading. This again lower media volume per acre.
What is the solution?
Like all green plants, algae can utilize only a very small fraction of insident light. The unused solar energy can be reflected to shaded areas using solar trackers. ***More on this at another time.
My patent pending bioreactor system has a much higher media volume per acre. A synchronized algae colony is exposed to alternate light and dark regimens. These large volume bioreactors are deployed closely to one another and sun light tracked to shaded areas using proprietary solar trackers. Depending on the cell cycle duration of the species, a daily harvest of 2,500 cubic meter to 10,000 cubic meter media per acre per day.
** Look out for my next blog post on 'Cell Cycle Management'
When it comes to algae yeild improvement, we usually complain about 'bottlenecks, trafficblocks and deadends'. Discussions in forums like this are usually superficial. Its mostly reproduction or cut and paste of published material. Perhaps, innovators and original authors seldom participate in forums and blogs.
Blown up baloons will burst under summer sun. We need to go real miles before we go green.
Everyone will agree that biomass yield can be improved several folds over current yields, if the so called bottlenecks are successfully addressed.
I would like to revisit those trafficblocks with a patent pending technology over the coming weeks on this forum, if there is serious interest. I expect honest comments and criticism from those who are serious.
In one of the most destructive natural disasters of recent history, powerful tsunami waves slammed into northeastern Japan devastating dozens of cities and killing thousands. As tsunami waves settles, panic broke in, with an explosion in one of the reactors in Fukushima Nuclear power plant. Today’s headlines say thousands of “nuclear evacuees wonder if they'll ever see home again”. Heat is building up in yet another reactor that might explode any time. And evacuation keeps going.
A strong and determined Japan, from the ashes of Hiroshima and Nagasaki, has emerged as one of the strongest nations in a relatively short span of time. It might take decades to heal the wounds but the nation will recover sooner. And we, from the bottom of our hearts, wish they do.
Now, I think, is the right time to revisit our clean energy efforts. Nuclear energy advocates force us believe it is rather safer source of energy. Yes, it doesn’t emit as much carbon dioxide or other flue gases as conventional energy sources do. It only explodes. Chernobyl is still live in our memories.
Those who are to ‘clean’ coal and other fossils offer us geological and ocean sequestration of carbon dioxide. Yes, it is possible to pump carbon dioxide into geological and ocean formations and believe it stays there for ever or at least for a thousand years.
Let’s forget the economics of nuclear power or carbon sequestration since technologies might emerge to make them economic.
But are they solutions? Will carbon sequestration and nuclear plants withstand such destructive earth quakes or other natural disasters? or are we going to dig the graves for future generation?
Last three days again remind us of a politics lead by capital interests.
Today, our clean energy efforts are focused on various alternative and renewable energy sources and also energy efficiency, Billions of research dollars are flowing into these researches.
But, are we in the right direction? I strongly suspect.
Out of all alternative fuel sources, algae is the most applauded one. But, what is the state of research in this domain? Is there something that draws back? The tragedy began with Aquatic Species Program. Once algae was identified as a potential source of alternative liquid fuel, the project was starved of funds. Finally, the project was rolled out, though they term it ‘close out’. Since then, what happened to the research? If you compare algae research with researches in other areas of science, you will see that algae research is quite a low profile one. a vehicle designed by man more than 3 decades is still exploring deep space and sending signals to control stations on earth. Why do we cry for scaling up of bioreactors and shading of algae cells in the second decade of 21st century? Don’t we have enough geniuses to sort out such simple issues?
For electricity generation, we have many clean technologies available. But, none has potential as a total replacement to fossils. Bur we do not care much for what keeps us on earth or what keeps the earth in its relative position to other celestial objects. I am talking about gravity- the omnipresent form of force. You may read tons of information on gravity, but you will not understand what is gravity. Physicists say, it is not energy- it is only a form of force. Many people believed, and still believe, that force of gravity can be used to generate useful energy. But science objects this concept since such a situation will violate basic principles of physics. The world of science is so united on this issue that no research is promoted on free energy including gravity harness and major patent offices do not allow free energy and perpetual motion claims. But thousands of enthusiasts continue researching it and few claim success. Many believe such technologies are suppressed or prohibited, while some others suspect existence of a ‘free energy conspiracy’.
I have two projects, one on algae commercialization and one on gravity power harness. I have pending US patents on both. But I am sure I have miles to go getting the claims on gravity harness allowed.