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YOU!: Fix the US Energy Crisis

  1. Aug 1, 2017 #1421

    OmCheeto

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    I thought you were the "aluminum air battery" advocate?

    ps. I don't know enough about chemistry to make any intelligent comments about either. As I've said many times before; "My brain is FULL!"
     
  2. Aug 1, 2017 #1422

    jim hardy

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    OOhhhh Yeah ,,, that one will make somebody rich. Natural for automobiles it runs on empty beer cans..
     
  3. Aug 1, 2017 #1423
    100% is tricky, and is very location dependent in a cold climate.

    That said, we have a 1983 house -- not even R2000 -- but with most of the glazing on the south side. The house is livable by solar heat down to about -10C on a sunny day. We heat with wood, and burn about 3 cords a year. We have gas, but it heats the domestic hot water only.

    Getting to between 80-90% is easily doable.

    Getting to 100% but not having it toasty (e.g. in a prolonged cloudy spell, your house may drop 10 C) is fairly doable.

    Problems:
    * With climate change we (I'm near Edmonton) are getting increasing stretches of cloudy cold weather. Insolation drops by about 2/3 If you get a stretch 2 weeks long, then you either have to store than many joules or you have to size your solar collectors to work with half the insolation. This requires a very different design. (It actually better to put up PV,. use what you need to heat water, sell the surplus to the grid. These glooms often occur in November coupled with temps in the -30's.

    * Current house design doesn't optimize roof angles for solar collecting. This would be a simple bylaw building code change.

    * The existence of trees in the neighborhood acts as a mixed blessing, reducing the number of hours of available light.

    * December at Edmonton's latitude (54 degrees north) makes for a 7 hour day with maximum solar elevation at noon of 13 degrees. (I use my car's sun visor driving south at noon...) Sunlight is short, frequently behind something, and attenuated by its long slanted path through the atmosphere.

    Super insulation --e.g. strawbale walls and 18" of cellulose in the attic, triple glazed argon filled windows, heat exchange ventilation -- can produce a house that for most of the year can be heated by the waste of the standard electrical load for the house.

    Retrofitting:

    * Tighten up the house. Few houses are as tight as one air exchange per hour and a half. If the rest of the house is R20, half your heat goes to heating new air. Cutting this in half is fairly straight forward: Door and window seals, seals around vents, and don't forget to check the seals around electrical outlets on outside walls. Recessed ceiling lights are another common heat leak.

    * Once you have the house tight enough that it starts to feel stuffy at times, then put in a heat exchanger vent system in. If you have a forced air furnace this is easy. If you have electric or hydronic heating, it gets far more involved. Multiple smaller units may work better, as they would require far less ductwork.
     
  4. Aug 2, 2017 #1424

    OmCheeto

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    Ha! I just got a "LinkedIn" invite from my nephew in law. He has a PhD in Chemical engineering, and is working on "Biofuels" research for a fairly large company.
    Perhaps I'll send him an email, asking his opinion about your Ammonia idea.

    Holy moses! 7 patents & 6 publications. Damn that kid is smart.
     
  5. Aug 2, 2017 #1425

    jim hardy

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    Beware Linkedin. They used to steal your inbox and send invitations to everybody in it . Made me hopping mad. I think they got sued for that and quit but check with nephew and be sure he really sent it..

    I get invites from people i never heard of. Would quit except i have found so many old friends there.

    Patents and publications ??? Sounds like Nephew is a chip off the old OM family block?

    old jim
     
  6. Aug 3, 2017 #1426

    OmCheeto

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    Actually, my "blood" relatives, like me, seem a bit daft. But they marry well.

    wow

    It took me ≈10 years to burn through ≈3 cords of wood. Even at that rate, I determined it was not a trans-generational, sustainable source of heat.
    My two trees were about 75 years old.

    You might want to study up more on how Drake's Landing works. They don't rely on "basically zero" über northern latitude solar power during the winter. All of that energy is stored during the summer.

    2017.08.03.silly.edmonton.canuck.png

    ps. I REALLY wish I had paid more attention to that MacKay guy, way back when.
    Ugh. Even Marcus was interested in that guy. And Marcus was "over the top" smart, IMHO.
     
  7. Aug 4, 2017 #1427
    The generic topic is 'passive annual heat storage' I'm familiar with it. It isn't trivial to do. A quick BOTE ignoring solar gain showed that it would take a thermal mass of soil/rock about 1.5 times the footprint of the house, about 8 feet deep, heated to about 180 F to store a winter's heat. The obvious way to do this is under the house. But as Nick Pine comments in his solar works, you don't really want to live inside the heat battery.

    In practice, you need the summer heat to level out the worst of the winter. It's your 'rainy day' fund of therms. This reduces the mass considerably, but you still need to insulate it very well to keep enough usable heat for 6 months.

    At the community level, PAHS can be accomplished with a covered pond. Take an acre of pond, 20 feet deep, cover to keep the wind down. (Float a layer of bubble wrap on it?) Saturate the lower level with salt. Add agents of prevent algae. Float a layer of something like oleic acid to eliminate evaporation. The result is clear water that doesn't convect. Sunlight is transformed to heat at the bottom, but the hot salt water is still denser than the cooler fresh water. If you can establish a density gradient it works reasonable well. You pull heat out with a heat exchanger in the fluid. However this also creates thermal disturbances, and in practice you need to pull heat at a rate that is compatible with diffusion, not mass movement.

    In practice the layers gradually mix. Upwelling salt water from the bottom hits the fresh water interface, and there is some mixing. It may be possible to find a plastic that is slightly denser than fresh water that could float on the layer of salt water.




    My typical year has 10,000 degree heating days (F) per year.
    It can vary about 20% on either side of that. Thats 240,000 degree heating hours. If your house is insulated at an average of R20 (Hard to do. Windows, doors, and air exchange bring it down) then each square foot of house envelope requires 12,000 BTU over the course of a year. So a 1000 sq ft house has about about 2000 sq ft of envelope, so now we are back up to 24 million BTU For you non-imperial units guys 1 million BTU ~ 1 gigajoule within about 5%

    I have 15 acres of poplar bush. Poplar has roughly a 50-80 year life cycle, and has a net biomass productivity of about 1 ton per acre dry weight. A ton of dry poplar is about a cord. So at this stage I'm using about 20% of the net biomass productivity of my woods. In the 20 years I've done this, I've seen some improvements in the age distribution of trees, and a marked increase in the number of species. Can't say for certain that one causes the other.
     
  8. Aug 4, 2017 #1428

    OmCheeto

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    Wondering if the average Canadian has access to 15 acres of Poplar?
    I'm guessing, probably not.
     
  9. Aug 4, 2017 #1429

    jack action

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    Well according to this site, 13.1% of the 347 069 000 hectares of Canadian forest lands are Poplars (by volume). Assuming a population of 36 millions, with an average 2.5 persons per home, each home can have access to 78 acres of Poplar! :cool::smile:
     
  10. Aug 4, 2017 #1430

    OmCheeto

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    I believe, somewhere in the past, that I determined that Oregon(Omsville) could not sustain a harvestable tree crop.
    And we're not Canada.
    It's like Siberia or something up there!
    Ok... Except for @DaveC426913 land, which freaked me out one day, as he lives 2° more southerly than I do, and Oregon isn't even on the Canadian border. ?????
    We're like, next to California.
    hmmmm.....
     
  11. Aug 4, 2017 #1431

    mfb

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    Exclude everything in areas where (nearly) no one lives and the number gets much smaller.
     
  12. Aug 5, 2017 #1432
    Well, the phrasing of the question implied, what was I doing.

    No, wood heat is not a sustainable solution for everyone. Air pollution makes it unworkable in cities.

    If I threw $40,000 at my house, I could likely cut my wood use to a single cord a year, but I would have to burn it outside, and move hot water around.

    There are a bunch of different solutions that will be location dependent. Anyone who lives on 10 or more acres rurally can heat with wood.

    Better insulation.
    Heat recovery ventilation.
    Solar design.
    Solar PV
    Smaller houses.
    Buried houses.
    Wear more clothes.
    Multiple dwelling housing.
    Domed neighborhoods. (Like the big golf air inflated golf domes.)
     
  13. Aug 5, 2017 #1433

    mfb

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    250 acres = 1 square kilometer. 25 persons per square kilometer is extremely rural by European standards. As in: Basically non-existent outside Scandinavia and Russia. Here is a map. The average density is 75/km2, and a large part of the area is not covered by woods.
     
  14. Aug 22, 2017 #1434

    Astronuc

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  15. Sep 11, 2017 #1435

    berkeman

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    Thread closed temporarily for Moderation...
     
  16. Sep 11, 2017 #1436

    berkeman

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    Thread re-opened after cleanup of a PMM discussion.
     
    Last edited: Sep 11, 2017
  17. Sep 11, 2017 #1437

    CWatters

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    Cost of offshore wind falling dramatically in the UK. Now requires less subsidy than nuclear..

    http://www.bbc.co.uk/news/business-41220948

     
  18. Sep 11, 2017 #1438

    mfb

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    And if the wind doesn't blow, we switch off all lights.
    Comparing the cost of a power plant you can regulate to the cost of wind-dependent power plants 1:1 just doesn't help.
     
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