Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Algae power

  1. Jun 19, 2006 #1

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    While exploring the information on biodiesel, it became clear that the feedstock for this all around. As it turns out, blue-green algae - cyanobacteria, or pond scum - is a good producer of hydrocarbons. Knowing that lichen is made from cyanobacteria and fungus, and considering the abudance of the oil allegedly present, it seemed that I should be able to pull a handful of lichen from a tree, smash it up in a glass of hot water, steep, strain, allow the water and oil to separate, dry what floats on top, and I should have a flammable residue.

    It worked!!! How about that? The stuff really does grow on trees.

    I guess I just had to convince myself that it really is that easy.
     
  2. jcsd
  3. Jun 19, 2006 #2
    Not exactly a solution to the energy crisis, but very interesting nonetheless. Any link saying what kind of hydrocarbons these are?
     
  4. Jun 20, 2006 #3
    Lichen are the fake trees you use to make Train layouts. :cool:
     
  5. Jun 20, 2006 #4

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Actually, it could be just that. The hydrocarbons are essentially vegetable oil that is easily converted to diesel fuel with about a net 350% return on the invested energy. It is estimated that an area the size of Texas could grow enough algae to replace all of the world's petroleum.
     
    Last edited: Jun 20, 2006
  6. Jun 20, 2006 #5
    Alot of plants can be a source of oil. You are saying lichen is superior to others in some important way?

    Also: you mention only diesel. That's a pretty "dirty" fuel. Can the lichen oil be refined to something that burns cleaner?
     
  7. Jun 20, 2006 #6
    Oops, my mistake. I was thinking of lichen growing on trees, like how impractical is that? Algaes make much more sense. I'm envisioning a large offshore plant of some sort...
     
  8. Jun 20, 2006 #7
    Well, if the hydrocarbons come from recent photosynthesis by algae or lichen... then it's zero-emissions, the CO2 emitted in the end is exactly what went into the algae to begin with. :cool:
     
  9. Jun 20, 2006 #8

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    No, but it was something that should contain a fair amount of cyanobacteria that is right outside the door. I just wanted to see if it was really that easy.

    Cyanobacteria are good producers of HCs, but the algae or microalgae chosen depends on the application. And from what I have read, there is opportunity for discovery in this area. After reading and reading and reading about what has been tried, what results were obtained, and what recommendations are made for further research, it comes down to either trying strains that are indigenous to the area, or developing hybrid strains to maximize HC production. MIT is running a system of green algae that removes CO2 from the exhaust gases from industrial processes - CO2 scrubbers that can be converted to fuel. It seems that green algae is best for this application. Seen below.
    [​IMG]
    http://oakhavenpc.org/cultivating_algae.htm

    The first part of the answer is that we don't want to refine it to a higher quality fuel. This is what kills the efficiency of the energy chain with ethanol. For every 100 gallons of ethanol that you make, at best it took at least 90 gallons of ethanol to make it. At worst, you are losing energy and really driving the system indirectly with petroleum or other power sources such as the electric grid. I would have to look to be sure of the precise number, but biodiesel is cited as yielding about a 350% return on the invested energy.

    All in all, biodiesel is much cleaner than petro diesel. So in addition to the new clean diesel engines, and even a diesel hybrid coming to the US from Honda this year, it seems that domestically produced biodiesel burned in modern engines is a practical option on all fronts. We address issues of national security, oil demand, pollution controls, and if you're sold on anthropogenic global warming, the system is CO2 neutral. Not to mention that it would be beneficial to keep the $500,000,000,000 or so spend on foreign oil, at home. Also, since we already have [will have] plenty of demand from the trucking industry, we can make the conversion without suffering the so called chicken and egg problem.

    http://www.usatoday.com/money/autos/2006-06-06-alternative-fuel-usat_x.htm

    Also
    http://www.americanlemans.com/News/Article.aspx?ID=1872

    And, this guy will be running biodiesel
    http://www.cld.co.nz/earthrace.htm

    This is a nice page for related links and info:
    http://www.castoroil.in/reference/plant_oils/uses/fuel/sources/algae/biodiesel_algae.html
     
    Last edited: Jun 20, 2006
  10. Jun 20, 2006 #9

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    One note of caution regarding all literature on biodiesel: The price of fuel has doubled or tripled since most was written. The reason that this is practical now is the price of fuel, which can only go up in the long run.
     
  11. Jun 20, 2006 #10

    Mk

    User Avatar

    I haven't seen anything critical of ethenol. I've only seen how "it will save us from our addiction to oil," and how good it is! What is bad??
     
  12. Jun 20, 2006 #11

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    We only get to keep at most ten of every one-hundred gallons made.

    Oh yes, these are the two biggest objections to ethanol. First, we can't possibly grow enough corn to replace gasoline with ethanol. Next, if we tried, people would have to stop eating corn. Ethanol puts food directly into competition with energy. Biodiesel from algae avoids this problem.

    We can also make ethanol from algae. In fact there is a specific path in the micro algae that selects either HC production, or sugar production. Some research is being done that seeks to control this mechanism.
     
    Last edited: Jun 20, 2006
  13. Jun 20, 2006 #12

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    ...and we can see how long it took to happen.

    http://www.theaustralian.news.com.au/story/0,20867,19535878-36375,00.html
     
  14. Jun 20, 2006 #13
    Ivan, thanks for the comprehensive, informative answers to my questions. This all sounds quite a bit more realistic than I thought at first.

    Your wording here:

    gives the impression you, yourself, are involved with some movement promoting this oil-from-lichen (or algae). Is that the case?
     
  15. Jun 20, 2006 #14

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Again, the best options for this are varous micro algae, not lichen. That was just a random selection for testing. And no, I'm not formally involved with any group yet but presently I am seeking some level of involvement. And since I have five+ acres, I might just grow some algae.

    When I say "we", I guess I mean us humans. :biggrin:
     
    Last edited: Jun 20, 2006
  16. Jun 20, 2006 #15

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Thread name changed to help avoid further confusion.

    But wait; blue-green algae is really a bacteria. :grumpy:

    Not my fault. Blame Moonbear and her kind. :biggrin:
     
    Last edited: Jun 20, 2006
  17. Jun 20, 2006 #16

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Okay, one more link. This is a thread that I started to explore the feasibility of FEGs that was somewhat derailed by a compelling argument for algae. This was the first that I had heard of a serious effort on this front. There was also a fair amount of effort to look at the real numbers for the current world energy demand and how various energy options compare. The bit about algae picks up on pages two and three.
    https://www.physicsforums.com/showthread.php?t=108344
     
  18. Jun 21, 2006 #17

    rcgldr

    User Avatar
    Homework Helper

    As I posted in another thread, it's much more efficient to make ethanol from sugar cane. Sugar cane could be grown in the south-eastern states of the USA, and is grown in other countries to produce ethanol. The issue with USA production is labor costs, as there hasn't been a machine made to harvest sugar cane. Because of USA labor costs, it's cheaper to import sugar than grow it here, so it's not grown in the USA anymore.
     
  19. Jun 21, 2006 #18

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Do you have any numbers handy? This is the thing about algae biofuel stocks that about knocked me over. These are seemingly representitive of the results obtained from real crops.

    Feedstock US Gallons/acre Litres/hectare
    Soybean............. 40............. 375
    Rapeseed.......... 110........... 1,000
    Mustard............ 140........... 1,300
    Jatropha ...........175............ 1,590
    Palm Oil ............650 ............5,800
    Algae ...........10,000 ...........95,000

    http://en.wikipedia.org/wiki/Biodiesel

    Algae is typically cited as yielding between 5000-15000 US Gallons per acre-year under well controlled conditions. Also, and this is key, it can be grown in salt or brackish water. It can also be used for sewage treatment.

    This brought to mind the notion of a self-contained chemobioreactor septic system that has a faucet and hose attached for filling your diesel tank. Can you imagine trying to convince people of what's really coming out of the faucet? :biggrin:
     
  20. Jun 21, 2006 #19

    rcgldr

    User Avatar
    Homework Helper

    I only know it's a lot better than corn, but I'm also sure it's not as good as some of the stuff you've listed here. It's very popular in Brazil. Do a web search for "sugar cane ethanol Brazil", you'll find a lot of hits.
     
  21. Jun 21, 2006 #20

    Ivan Seeking

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    I was aware of Brazil's recent fame but didn't know how sugar cane compares to corn wrt energy demands or the gallon per acre yield.

    http://www.gather.com/viewArticle.jsp?articleId=281474976746069

    So it certainly seems to be a much better option than corn. Of course we haven't looked at the cultivation costs which I suspect will be the great equalizer. Algae will cost much more per acre to produce than corn or sugar cane, so all options could be competitive for now.

    Note also that the precise numbers for corn produced ethanol are hotly debated. From what I have read, a 10% return on invested energy is more like it. Some scientists still argue that the system is a net negative energy yield.
     
    Last edited: Jun 21, 2006
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Algae power
  1. Pee Power (Replies: 0)

  2. Muscle Power (Replies: 6)

  3. Power of the Internetz (Replies: 12)

  4. Power Balance (Replies: 11)

  5. "Knowledge is power" (Replies: 11)

Loading...