Laurens Rademakers conducted the following interview with Dr. Krassen Dimitrov, who recently made an in-depth analysis of algae-to-biofuel concepts. The scientist remains a skeptic and outlines why he thinks it won't be easy to utilize the micro-organisms to produce large amounts of renewable fuels. He also sketches his view on more promising sustainable energy concepts, and on the challenges ahead to mitigate climate change. Dr. Dimitrov works at the Australian Institute for Bioengineering and Nanotechnology (AIBN, University of Queensland), where he carries out research at the interface of biotech and nanotech.
Biopact: A while ago, you started writing about biofuels made from algae and you have serious doubts about the potential of this technology. What is the basis of your skepticism?
Dr. Dimitrov: Interest in biofuels rises with clockwork regularity whenever the words 'energy crisis' enter the news. This was the case in the 1980s and all of the options, including microalgae, were considered and heavily researched back then. My own interests in biofuels began in the 90s as I considered them for my next career move.
The reason algae are always quoted as the 'perfect' feedstock is that they can grow extremely fast in optimal conditions. In Mother Nature, however, 'fast' is not always a winner, or else the entire biosphere would have been overtaken by bacteria, which can divide every twenty minutes.
Fast proliferation is usually at the expense of rigour and adaptability. Plants do not grow as quickly as algae, however, they have elaborate mechanisms that allow them to survive and grow in various conditions, so they require less care and lower expenses for cultivation.
Therefore, with algae one has to always consider the trade-off between high growth rates and how expensive it is to maintain conditions that would allow them. The other very important boundary is imposed by thermodynamics - the yield is limited by the amount of energy (sunlight) available – so improving the cultivating conditions follows the law of diminishing returns, as every percentage of yield that one can wrestle out becomes harder and harder as one approaches the theoretical limit.
Biopact: You made things concrete by writing a case study on the technology of a particular algae-to-biofuels company, GreenFuels Technologies. What were your findings?
Dr. Dimitrov: GreenFuel Technologies gained notoriety for their heavy promotion of microalgae cultivation in photobioreactors (PBRs), however, following the considerations above, this is probably the most absurd approach that can be undertaken. While it is expected that PBRs would be best suited to allow maximum growth rates, these are hardly devices that cancel the laws of thermodynamics. In my study I have shown that while it may be theoretically possible to achieve growth rates that are up to ten times higher than the best terrestrial growth rates (in the tropics), the expenses associated with PBRs are hundreds of times larger than terrestrial cultivation, making PBRs economically illogical:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: algae :: biology :: biotechnology :: nanotechnology :: renewables ::
My GreenFuel study [*.pdf] focused on industrial photosynthetic capture through PBRs, which are the most expensive extreme in the algae sector. Going down the expense curve, there are approaches - such as open ponds - that are less expensive; potentially there may be some optimum, where microalgae cultivation becomes cheap enough yet with sufficient control over external conditions to secure reasonable yields. Open ponds, are still iffy in my opinion, however, they are not as absurd as PBRs.
I presented my study to Jennifer Fonstad, who is currently the chairman of GreenFuel, on March 15th. I have not heard directly back from the company, however, they had circulated a response, that I found lacking, and that can be found here.
Interestingly in their latest releases, GreenFuel avoids using the word 'photobioreactor', and instead prefers 'greenhouses'. I have seen a schematic of their 'third generation design' and it is basically an algal pond with bubbling CO2 that is housed in a greenhouse. From that we can safely assume that the bioreactor is dead, after millions of dollars were spent on it and GreenFuel is now in the business of greenhouse aquaculture. This is not going to work either, eventually they will either have to shut down, or join the other companies that pursue open ponds.
Speaking of how GreenFuel responds to criticism, I just have to mention that the company had threatened a very prominent scientist, with decades of experience in algal research who, when asked about their approach, had expressed a strong skepticism. When I saw the legalistic threat against this legitimate skeptic, it made me truly infuriated. Misusing the legal process to shut up scientific experts can only be described as medieval.
Biopact: So what's your assessment of algae-based biofuels for the longer term? Will the technology ever be viable on a large scale?
Dr. Dimitrov: The answers above partially address this issue. There is no question that microalgae have the potential for high productivity per area, albeit with all associated high cultivation costs. In certain Malthusian scenarios of the future one can envision that land becomes so expensive that humans will need to highly optimize its use, for animal feed, for example. In terms of making significant contribution to energy in the next 20-30 years, though, the answer is a sound 'no', and if somebody wants to bet me on that, I would gladly take that bet.
Biopact: You conclude that there is a real 'hype' surrounding algae biofuels. But the sector is attracting some serious money from venture capitalists. How can investors be so blind to basic physics and biological laws, which you demonstrated to work against algae biofuels?
Dr. Dimitrov: Some venture capitalists can be blind, ignorant and disrespectful towards science, there is no question about that and I have experienced it firsthand. This is, however, only one third of the answer; there are two other factors at play.
First, some venture investors operate on the principle 'find the bigger fool'. When they start a company they don’t think about building a long-lasting business, but rather making it attractive to somebody who is less sophisticated, such as a big bureaucratic corporation, or alternatively, promoting it to the public with the help of corrupt investment bankers. We saw this with the internet bubble a decade ago: established businesses paid crazy money for unproven internet startups; the scandals with investor bankers and analysts shamelessly promoting Internet IPOs. Undoubtedly, there is a current hope that something like that will develop around alternative energy.
Second, investing in fancy alternative energy startups helps some venture capitalists in their fundraising. VCs are paid a fixed percentage of assets, which is irrespective of how well they do. Getting money from limited partners is extremely competitive and it helps their 'dog and pony show' to demonstrate that they are abreast the fashionable green energy wave.
Ultimately money changes hands, but no value is created, so who is left holding the bag? All evidence points that it is the pension funds who will get shafted. Due to demographics in the Western world there is lot of retirement money that need to be invested now; unfortunately with investor managers like these some people will have retirements that are less comfortable that they would have hoped for.
Biopact: So let's consider algae to be out of the race for now. The global energy and fuel crisis, as well as climate change, will have to be tackled in other ways. What do you see as absolute priorities to help solve these intertwined crises, when it comes to our energy consumption?
Dr. Dimitrov: These are two separate issues: for the energy and fuel crisis we have strong market forces in place, while for global climate change we don’t.
Because of that the fuel issue is actually being addressed, here are examples of things that are significant now and that were not fifteen years ago:
- Tar sands are increasingly becoming exploited for oil production, the volumes have grown a lot, especially in Canada.
- In some countries, for example in Eastern Europe, people are en masse retrofitting their cars to run on compressed gas. [Note: Pakistan would be another example of a successful CNG program; the country succeeded in converting 1 million cars in under two years time - more here]
- Bioethanol has grown dramatically. At current oil prices ethanol from sugarcane is very competitive: Brazil has the land and the intent to go much further in that regard.
- Hybrid cars that consume significantly less fuels are becoming very popular in the Western world.
- There are many gas-to-liquid and coal-to-liquid projects in various stages of development around the world, in Qatar, China, and Papua New Guinea.
In terms of climate change the market just doesn’t work and things will get much worse before they get better. Especially since some of these fuel alternatives above that are most cost effective, such as CTL and tar sands, actually have a larger CO2 footprint than conventional oil. There is a great article on that by UC-Berkeley. This CO2 from emerging liquid fuels is in addition to the new cohort of coal-fired power plants that is coming online.
When the world gets to actually doing something concrete and meaningful in regard to global warming, I strongly believe that the only option left would be to scrub CO2 from the air, I will be writing on that in the near future.
Biopact: You are working in the field of nanotechnology and at the interface of nano- and biotech. Do you see any interesting developments in these disciplines that could lead to clean and affordable energy?
Dr. Dimitrov: Yes, as a way of introduction, let me continue from the previous question. One approach that experts agree is a most technologically ready form of non-carbon energy production is Concentrated Solar Power. It is a viable solar conversion approach and we will likely see CSP grow in significance. CSP generates electricity, however that does not address the transportation sector, as the problem with electric cars is still their range. We believe that nanotechnology can play significant role in designing batteries with higher and higher energy densities so that electric cars charged on CSP electricity can become reality. At AIBN we have several projects on using nanotechnology for improved battery performance.
Realistically, I don’t expect that energy densities will ever approach these of liquid hydrocarbons, however, electric cars, in addition to lowering emissions have other benefits:
- better efficiencies of electric motors compared to ICE. While a tank of gas will always contain more energy than a battery with a similar volume, less of this energy goes to the wheels in the ICE than in the electric car
- less noise pollution: a factor in big cities
- better acceleration, electric cars are fun to drive
Biopact, cc, 2007.
Picture: Tetraselmis Suecica, a large green flagellate with a high lipid level that was tested extensively during the U.S. Aquatic Species Program in the 1980s.
Dimitrov, K. "GreenFuel Technologies, a Case Study for Industrial Photosynthetic Energy Capture" [*.pdf] - Brisbane, Australia, March 2007.
Dimitrov, K. "GreenFuel Technologies: Case Study for Industrial Photosynthetic Capture - Follow-up Discussion" [*.pdf] - Brisbane, Australia, April 2007.
Updates on Dimitrov's analyses of algae biofuels can be found here.
Biopact: An in-depth look at biofuels from algae - January 19, 2007