Biogas is renewable energy's Cinderella

Discussion in 'Emissions' started by Carcus, Jul 30, 2012.

  1. Carcus

    Carcus Well-Known Member

  2. herm

    herm Well-Known Member

    Interesting.. making methane has to be the least economically viable thing you can do today, it pours out of the ground for free.

    Drying the ethanol produced from corn is very energy intensive.. it has to be dry because it will be blended with gasoline.. but you dont have to do that is you dont use gasoline at all, plus the engine can be optimized for ethanol.

    I believe making methane out of corn silage uses up all the plant, nothing is left at the field, no animal feed supplements are made, no corn oil extracted etc..
  3. Carcus

    Carcus Well-Known Member

    All the "advanced" biofuel process involve 'syngas' (ie converting to gas first, then to a liquid) so it makes sense that stopping in the gas phase would be more efficient.

    I don't know that corn would be the best crop to work with in methane production.

    Here's a video that shows herb leftovers (among other things) with nutrients back to ground leftover:

    Another "Cinderella story" is the Kalmari farm in Finland-- a centuries old family dairy farm where the cow shlt is now worth more than the milk.
  4. NeilBlanchard

    NeilBlanchard Well-Known Member

    If every sewage treatment plant and big farm had methane digesters, then we would go a long way to lowering our carbon output. And natural gas from underground is anything but free.

    Peaker plants should all run on biogas.
  5. ItsNotAboutTheMoney

    ItsNotAboutTheMoney Super Moderator Staff Member

    Not sure that's the best way. It might better to treat and pump into the general NG infrastructure.
  6. Carcus

    Carcus Well-Known Member

    "Nonetheless, the expansion target for biogas plants in France of 625 MW by 2020 is quite conservative in relation to the available resources. France is thereby utilizing only 5 % of its biomass potential for energy generation according to figures from the European Biogas Association EBA. For comparison: the EBA says that Italy wants to have 1200 MW of electrical capacity from biogas by 2020, Great Britain 1,100 MW and Poland 980 MW. The Netherlands intends to install 639 MW and the Czech Republic 417 MW."

    How to build a biogas plant
  7. herm

    herm Well-Known Member

    I can guarantee that it is more expensive than fossil methane right now (in the US).. how would you feel about paying $0.50 per kWh of electricity like they do in Germany?

    I think that by definition biogas comes from a biological digester, not from gasification.
  8. Carcus

    Carcus Well-Known Member


    Ng is at historic low prices in the US right now while German Electricity is taxed at 41% (perhaps you were already aware).

    Can we keep the thread oriented a little more towards physics and long term practicality ........ hmmmmm?
  9. NeilBlanchard

    NeilBlanchard Well-Known Member

    Methane digesters are not all that expensive.

    The current price of fracked natural gas is because there is a funding bubble. And it in no way represents the actual real costs; which include numerous small earthquakes, contaminated wells and groundwater, and climate change.
  10. CRT1

    CRT1 Newbie McNewbster

    Energy in vs. energy out is not the important thing for the near term. While energy is still relatively cheap and the world leaders have their heads in the sand about climate change.

    The pertinent information is the cost per unit of energy. This of course is largely dominated by infrastructure capital costs and production costs. Can biogas be produced cost effectively?

    Physics and chemistry are interesting to you and me, but in the real world money talks and suckas walk.
  11. herm

    herm Well-Known Member

    I was thinking that in the future you throw some switchgrass in the digester, roots and all, add some cultured bugs and you can literally get anything out of it at low cost.. including high quality human food, plastics, medicine, rubber etc.
  12. Carcus

    Carcus Well-Known Member

  13. herm

    herm Well-Known Member

    in 50 years!

    Its actually cheaper to make biobutanol than to extract it from oil.
  14. Carcus

    Carcus Well-Known Member

  15. Carcus

    Carcus Well-Known Member

    "The biggest reason however, why biogas should be given a lot of consideration, is the fact that it can generate a large net quantity of bio-energy per ha cultivated. Much larger amounts of bio-energy can be produced per hectare of land utilized in the form of biogas than compared to the net energy yield for bio-ethanol and biodiesel. Production of biomethane will power a car three to four times further than using the same land for production of bio-ethanol and biodiesel. Almost all of the biomass is converted to biogas through the digestion process. Also the quality of the crops can be rather low so that energy crops can be harvested before they are mature. This enables the farmer to grow two crops per year on the same field, increasing energy yield immediately by another 20 to 30%. Additionally, digesters can be constructed more locally, within a transportation radius of 5 to 10km for the feedstock, while transportation for central biodiesel and bio-ethanol plants can be a large negative factor in the overall net energy yield. Digestion can also utilize a wide variety of feedstocks and crop residues."

    Dry continuous anaerobic digestion of energy crops
  16. NeilBlanchard

    NeilBlanchard Well-Known Member

    Yes, biogas can be produced economically -- they are using it in Germany. The "fuel" for methane digesters is virtually free, and the resulting slurry after all the methane has been produced is a high quality fertilizer. FYI: we are currently using natural gas to make fertilizer that sucks, because the nitrogen is not fixed and it runs off in the first rain -- and causes a whole string of major issues like dead zones in the ocean and lots of nitrous oxide, which is a powerful greenhouse gas.

    So yes, biogas is a lot more "economical" than natural gas. And no, we can't continue to use finite fossil fuels -- renewable energy is by definition the only way we will solve our problems.
  17. phoebeisis

    phoebeisis Well-Known Member

    While the economy in the USA is poor-8% officially unemployed-actual unemployed maybe 12%?
    We will use the energy that is CHEAPEST in the short term-short term meaning forseeable costs must pay costs-in the next year.
    So earthquakes- clean up problems-potential water contamination(not saying to regularly happens-don't know) JUST DON'T COUNT!
    Poor economy-pols not brave enough to look long term.
    NG is under $3 per whatever-I remember maybe 507 years ago it was $14 per whatever unit
    So NG is DIRT CHEAP-heck cheaper than coal when you consider cola miners have to die or get sick to get tunnel mined coal

  18. herm

    herm Well-Known Member

    So we are all agreed that we have a bright future for out kids energy needs once fossil methane runs out?.. lots of jobs harvesting all those crops and turning over the dry compost heap. Combine this with that new home methane compressor by Eaton and we are set.
  19. herm

    herm Well-Known Member

  20. Carcus

    Carcus Well-Known Member

    My (very rough) guestimate is that IF we were to reduce our liquid fuel consumption to 1/3 of peak (i.e. 2007 ish) then we could replace that fuel by dedicating 20% of our grassland to biomethane production.

    Seems high but achievable to me, and much more realistic than any "renewable liquid fuel future" I've seen presented.

    The biomethane future would of course involve wind, solar, hydro, nuclear and massive amounts of efficiency upgrades and conservation. By comparison, biofuel seems to offer little more than running in place and a massive waste of tax dollars and time. I'm not so sure that we've got 50 years to figure this out. :flag:

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