Talk:CH391L/S13/Algal Biofuels

• Kevin Baldridge 16:49, 18 March 2013 (EDT):What are you referring to with "photosynthetic efficiency"? You say sugarcane is the best, but algae actually have more energy per mass. So what is the final product which you are comparing, simple sugars which can be converted to alcoholic biofuels?
  • Gabriel Wu 17:12, 18 March 2013 (EDT): Agreed. You're comparing sugar content in corn and sugarcane to lipid production in algae, but you compare them directly. This could use some further clarification.
    • Aurko Dasgupta 01:30, 25 March 2013 (EDT):I admit that I described the comparative efficiencies quite poorly. I hope the section is clearer now. What I had set out to describe was that although sugarcane incorporate a higher amount of light energy as chemical energy (but, as I found out, this is only under highly optimized conditions), algae can produce a greater energy equivalent through biodiesel per unit land than sugarcane can with ethanol.
• Catherine I. Mortensen 16:57, 18 March 2013 (EDT): Is it possible to somehow use chlorella that already exists in the ocean to produce fuel?
  • Aurko Dasgupta 17:42, 18 March 2013 (EDT): I doubt that ocean algae consistently grows in a concentration high enough to justify the energy required to power the extraction. They're also wild, so they're not as optimized for any specific feature of biofuel production.
    • Thomas Wall 21:12, 18 March 2013 (EDT):Ok this is a pretty picture of an algal bloom near where I used to work [1] as far as natural occuring algae this guy is the best I've heard of [2]
• Gabriel Wu 17:17, 18 March 2013 (EDT): Can you cover a little more of the molecular biology? How are algae actually genetically engineered to improve lipid content? Which pathways are targeted and is there heterologous expression of genes to optimize these pathways?
  • Max E. Rubinson 11:25, 21 March 2013 (EDT): I think maybe you should also include a discussion of how strains with truncated light-harvesting antenna are engineered? This paper describes how the Melis lab generated strains of green algae that exhibit a truncated Chl antenna.
    • Aurko Dasgupta 01:26, 25 March 2013 (EDT):Thanks, I included this paper on the photosynthetic efficiency section. Although they worked towards hydrogen production, energy capture works the same for all biofuels.
  • Thomas Wall 21:25, 21 March 2013 (EDT): Also I think you should have some mention of cyanobacteria (blue-green algae). Here is the patent my old company had on the process [3] and here is a link to a coculture dream I didn't have but wanted to [4]
    • Thomas Wall 21:43, 21 March 2013 (EDT): good reference for metabolic engineering in green algae [5]
• Jeffrey E. Barrick 22:53, 20 March 2013 (EDT):People often mention "red tide" when talking about algal biofuels. A possible danger of growing large vats of algae is that they may produce toxic compounds. Did you encounter that in any of the articles?
  • Thomas Wall 21:25, 21 March 2013 (EDT): This is definitley a nontrivial concern, I know cyanobacteria can produce some nasty stuff [6]. I think most harmful algal blooms in eukaryotes come from dinoflagellates, which are researched for biofuel production [7].
• Yunle Huang 10:04, 21 March 2013 (EDT):How are the biofuels actually collected? Are the cells just lysed, or is there an extraction method that keeps the cells alive?
• Dwight Tyler Fields 12:59, 21 March 2013 (EDT):You might also want to include a "Future of Algal Biofuels" section that gives current scientific opinion on the future viability of the field. I'm finding a mostly negative outlook, ex: [8]
  • Aurko Dasgupta 02:08, 25 March 2013 (EDT):I honestly didn't find that article all that negative. Like many things, they are a bit overhyped, and but even the ending message of the article was "I'm not going to say algae is going to be the optimal choice, but it's a good candidate." Also, added a future directions section.
• Neil R Gottel 15:08, 21 March 2013 (EDT):I really love the idea of coupling a coal power plant to a nearby closed algae biofuel production facility. The carbon is ran twice (lower emissions), and the algae are more efficient due to the increased CO2 concentration (less land area). Plus, you get both electricity and liquid fuels out of this scheme. Unfortunately I can't find actual research papers on coupling coal and algae, only blog posts and news articles...
  • Benjamin Gilman 19:28, 21 March 2013 (EDT): I'm having a hard time finding anything specific about it too, but I know there was a pilot plant set up in CA or AZ that used algae to trap about 5% of the CO₂ output of a small natural gas power plant. Land use was still a huge issue, because the algae tanks covered much more area than the plant but didn't actually use most of the emissions. One argument has been that this kind of arrangement might help subsidize the cost of algal bio fuels if emitting carbon starts costing significant amounts of money (as in a carbon credit trading scheme).
  • Catherine I. Mortensen 14:04, 22 March 2013 (EDT):This company called BHS is looking to establish their algae farms next to coal plants. Whether they have actually done this yet, I'm not sure... [9]
  • Aurko Dasgupta 02:12, 25 March 2013 (EDT):This is the best I could find for feeding industrial emissions into algal cultures.
• Thomas Wall 21:33, 21 March 2013 (EDT): So this is a cool company that is using algae to make fuels in fermenters [10], cool stuff imho.
  • Catherine I. Mortensen 22:15, 21 March 2013 (EDT):It's interesting to me that this microalgae prefers the dark. It seems like a very energy efficient and cost effective method of creating fuel.
• Siddharth Das 00:54, 21 March 2013 (EDT): I was wondering if you're talking about algal biofuels, then maybe you can add a practical methods that may utilize such fuel i.e. bioreactors. Also, do you happen to know efficiency of algae systems for solar energy production? I think this would be really relevant to Tyler's "Future of Algal Biofuels".
• Catherine I. Mortensen 14:17, 22 March 2013 (EDT): With the use algae biofuel carbon dioxide is still released into the atmosphere. Is it a good idea to continue using fuel like this considering the effect carbon dioxide has on the atmosphere and climate? A problem that might occur if the world became dependent of algae farms would be a carbon source to feed the algae (especially if the algae was grown in a closed container to prevent contamination.... the algae wouldn't be exposed to carbon dioxide in the air).
  • Aurko Dasgupta 20:57, 24 March 2013 (EDT):Every carbon the gets released by burning a biofuel came from the atmosphere in the first place. Some biofuel reactors actually use the gas waste from fuel burning plants to give algae a more concentrated carbon source and reduce emissions at the source.