Creating power for your home, off grid.
Emphasis on nuts-n-bolts, hands-on projects.
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The whole idea of growth through cheap labor, energy, and resources is how the world economy has evolved over the last 400 years or so. At least 300, anyway. We have completely abandoned the idea of a steady state economy model - one where these resources and their usage is more constant. I think the evolutionary pressure to keep on this path is too great to change until some catastrophic event. Wish it wasn't so, but don't see another path opening up.
Couple of observations...the source of oil - from dinosaurs. Well, there was most likely a carbon contribution from the flora and fauna of the time, but there is a whole lot more to the story that we don't have even a glimmer of a clue about. I'm gonna make a sweeping statement here - I absolutely DO NOT believe there were ever dinosaurs growing on Titan - one of Jupiters moons. But the atmosphere consists of about 1.4% methane - the hydrocarbon. Which raises the question - where did it come from? Which leads to the conjecture that the process probably occurred here and is probably ongoing. At what rate is a huge question!
I think if we stopped population growth today - got it to that "steady state" condition - it would still not be enough. Can't see the planet continuing to support these billions indefinitely. Will likely have to have a reduction. That is the nasty bit of the process. China's one child process appears to have been so successful that in another 50 to 100 years they may well have a population crisis that will create problems with the active participants too small in number to continue their projected level of economy.
Bio-fuels - we are using stupid amounts of corn to do this now. Yield is a couple hundred bushels per acre in good times. That gives about a ton per acre (55 lbs per bushel avg). Not sure what people are doing now, but as early as WWI, we were getting about 50 gallons of ethanol per ton of biomass. That may go up some with better refining/distillation processes, but that's a good number as reference. Growing switchgrass gives around 7 to 10 tons biomass per acre (same 55 gallons per ton). Much better.
But by far and away the best is marijuana. Yields are 12 to 14 tons of biomass per acre - one of the highest yields on the planet! With so little effort required that it is insane that we use corn for ethanol. You plant the seed and wait. Don't need to fertilize much - it will help some, but not really needed - marijuana grows well in fairly sparse soils. And why would anyone ever use an herbicide to keep down weeds? It IS one. It will choke out most others. And if it doesn't, well, that means just that much more biomass. Win, win, win, win.
But that would be directly against the interests of Dupont, Cargill, ADM, DOW and a wide variety of traditional agriculture interests. It is too simple. Too cost effective. Too elegant a solution. And too right! And that doesn't even count the excellent medical and recreational benefits of the plant!!
Ok, off the soap box for now...
For the kind of yields mentioned, won't need much fertilizer, NO tilling beyond initial planting, and no herbicides, cause some extra weeds would be just that much more mass. It is about as close to a perfect solution as can be found.
Sugar cane would give more mass per acre (30 tons) but requires massive doses of fertilizer and herbicides and tilling, very much countering the benefits of the extra mass. Switchgrass is pretty good, but still more commotion required than marijuana, and only about 3/4 the yield in mass.
Corn (as reference) requires about 1.25 lbs of N. 0.6 lbs of phosphate, and 1.4 lbs or potassium to produce 1 bushel of corn. High yield areas that get a couple hundred bushels per acre take a LOT of fertilizer. Crazy using corn for ethanol!! Beyond crazy - criminal!!
It is very difficult to get comparables on growing marijuana, but it is MUCH less. At least some "home growers" appear to recommend a product called "Ripen", (0,6,5) with magnesium. But that is small scale stuff. Not acres. Past experience of "some" shows good results with "free-range" growing.
One thing I do in my yard is to make sure there is plenty of white clover - the stuff you get "4 leaf clovers" from. Let it grow and seed before ever mowing it in the spring. Then, when May/June arrives and it gets hot, the clover dies out, but leaves the N fixing root system in the bermuda yard. The areas that have clover are always noticeably greener than the non-clover areas. That's why I try to get it to spread as much as possible. And alfalfa is MUCH better at it than white clover.
It seems like most of Australia is desert, so the use of ground water for irrigation will make a huge difference. New Zealand - I have no clue about the climate. Google Earth shows a lot of green, but that could be high dry woodlands for all I know. Much of our west shows green, too, but it is desert under the pine trees. Water out of the ground means a whole different set of things happening - different mineral combinations - that can be very good or very bad. ( In a real world, like a couple hundred years ago, the central valley in California would not have any green anywhere, so that would not be a good candidate for this crop. Keep that water and fertilizer to other value-added crops. Strawberries! Avocados!)
University of Missouri - nitrogen cycle
This one shows how much rain deposited N there can be around the US. Kilos per hectare. Page 3.
http://nadp.isws.illinois.edu/lib/broch ... trogen.pdf
Bottom line - yeah, there ain't no free lunch. But this stuff is a VERY cheap lunch - better than "peanut butter and jelly" in relative costs per ton to grow. 2,000 lbs corn - 1 ton - at 56 lbs per bushel - 43 lbs of fertilizer per ton. At 50 gallons ethanol per ton, that is close to gallon per 1 lb of fertilizer. Yuck!
If used the same amount of fertilizer - very good amount for bermuda/fescue pasture - overkill for marijuana - then you get about 14 gallons ethanol to 1 lb fertilizer. At least 14 times better. And using mowing for "weed" control, gives 85 to 90% effectiveness rather than herbicide - but who cares, it's more biomass.
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I have owned hemp clothing, and it is amongst the most comfortable and long lived that I have had, good in both warm and cool weather. Hemp paper is with out a doubt of very high quality. It has been said around the time prohibition came in, that suitable bird seed couldn't be had without hemp seed being in it, such was the quality (particularly with the oils contained in it). Hemp rope, is without a doubt the finest quality for natural fibre, though it simply cannot compete with modern synthetic ropes for practical purposes on boats.
Now to the growing side of it. The fallicy that it doesn't require much fertilizer is just pure bunkum. The feeding requirement for hemp is much the same as tomatoes or capsicum. It is a heavy user of nitrogen, pre-flowering, as any fast growing, green leafy plant is. Rain simply will not provide the nitrogen requirements in and of itself.
The big savings is in all other aspects of growing right up to harvest. Herbicides, insecticides (much less of a problem), and harvesting with less complicated/expensive machinery. Plus, that 14:1 ratio of fertilizer mentioned is still pretty close. No, ethanol feedstocks will never be free - but they can be 14 times less cost. That sounds awkward - how about 1/14 the cost?
For the US, from Oregon to Oklahoma to Ohio, the consensus seems to be about 60 kg/ha, or about 50 lbs per acre. This is on a par with bermuda/fescue pastures we have in similar areas. (Alfalfa needs the same size shot when planted, but then becomes its own little nitrogen plant while growing, so no more needed - but the yields are only around 4 tons per acre in mid-US.)
And green manuring with a field full of alfalfa can easily give one or two cuttings of hay a year (in Oklahoma), then leave the plants in ground overwinter and the next year, there are a few tons of green manure per acre for the next years MJ crop, already in the ground. (Green manure from alfalfa here is about a 1% N content).
The main thing is that we can do much better than the insanity of growing corn for an ethanol feedstock. At least an order of magnitude and more - 10X +.
I also appreciated the way the video "does the math" on exponential growth economy. Edward Abbey was the first person I encountered who pointed out that the only "constant growth" paradigm found in nature is a cancer cell. I believe we all know how that one works out.
I confess to finding some amusement in the discussion we have posted in response to the video. Does it matter how much nitrogen it takes to grow biofuel in a world that no longer provides the resources to build and maintain motorized vehicles and the infrastructure they require?
Where I live, we got a glimpse into what's coming during the aftermath of Katrina. We are several hundred miles from New Orleans, but the pipeline that supplies most of our gasoline was compromised, and in a few days, the price doubled. When we could find a station that had inventory. Most folks held up well for that few weeks, but still some tempers flared. The financial crisis of '08/09 was similarly sobering. I remain convinced that the only reason we're not experiencing world-wide recession now is that the US government spent a container ship load of cash propping up the fat cats. That well might be dry for the next round.
I was in college in '73 and newly married when the '79 shortages hit. I suspect that such events will be remembered as "the good old days" when real interruptions begin. Watching this video has helped me refocus some core convictions that I have been ignoring. One of those is my belief that we are headed for something remarkably similar to a preindustrial existence. Of course the world will never be the same as it was in 1880, but no one can deny that abundant, cheap energy is what made the incredible change of the 20th century possible. Well, it's a whole new ballgame.
I've stopped thinking in terms of converting an MCI bus. We'll get by in our step van. We already can't afford to drive it much, so what does it matter if the fuel economy is lousy. If I do build something different, I'm back to thinking that a wagon-type chassis would be a good move. Something like that could be pulled by anything. I wouldn't be surprised, though, if we discover that we won't be traveling much.
Thanks to all who contribute to this forum. I value your input.
Jim in NC
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