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Oil, global warming, time and agriculture

lionking said:
I agree with that, but am skeptical about the "peak oil now" theorists.
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Any particular reason for your skepticism?


'Have government agencies been attempting to hide Peak Oil for fear of setting off a financial panic?'

A second senior IEA source, who has now left but was also unwilling to give his name, said a key rule at the organisation was that it was "imperative not to anger the Americans" but the fact was that there was not as much oil in the world as had been admitted. "We have [already] entered the ‘peak oil’ zone. I think that the situation is really bad," he added.

http://www.guardian.co.uk/environment/2009/nov/09/peak-oil-international-energy-agency
 
Dancing David said:
Makes some sense, some people burn maize in stoves.

If the heat capture profile was high it would make more sense, especially if the efficiency of the engine was high.
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There are limits to the efficiency of a steam engine, and even MORE limits to the efficiency of a MAINTAINABLE steam engine.

First, a non-fixed plant steam engine is rarely going to be the Watt cycle, with a condenser, but will exhaust steam to the air. It will use that steam to create a draft which helps somewhat.

You can make sure the steam is very dry with a superheater, and that helps some, and is not a HUGE burden of maintenance if you design it right, but is increased first cost.

You can have a compound steam engine in which steam is expanded once in a high pressure cylinder and again in a low pressure cylinder, but even very cost-averse railroads found that compound engines were much less effective that superheaters.

If you CAN manage to have a condensing superheated compound engine and with modern materials not have it be a maintenance nightmare, you should get 25% efficiency.

A saturated-steam single expansion Stephenson type engine will be (including boiler) around 10% if competently designed and maintained.
 
I may as well dump an old idea I had in here. !Kaggen may appreciate it:

In a large, flat farm field, a strong post is set in the ground. A very basic tractor-type device is connected to the pole by a long cable. When it is turned on, the tool travels in slow spiral motion toward the center post, the cable being wound around the pole. When the tractor reaches the end of its run, it hits a switch, and reverses direction; spiraling slowly back out to the furthest reach, or radius.

Such a system could be used without drivers, or even steering. A variety of implements could be attached, including a wagon to allow picking and planting. A different crop could be planted on the spiral out.

If you're still with me, lay out 7 pennies on the desk, in a circle, with one in the center.
Each penny represents one of the system units described above. It is easy to see how this could be arranged so that the final out-winding of the cable lands at a point on the circumference of the inner penny. The center system has an access point to all the other circles. This facilitates exchanges from a central area with minimal complexity of machinery, compaction of soil; errosion; energy in-put, and so on.

The intercises between the circles are fallow, or decorative, or green manure crop.

after a few years (?) the posts can be moved, or modified, to allow a new spiral that covers the old spaces. These same lines that would permit driverless machinery, could be used as power lines and irrigation lines. Roads into the system wouldn't be needed. The default position of each "tractor" would be on the perimeter, allowing access to any other circle.

I've got a boat load more wild ag. ideas, and even some successful experiments.
I generally keep them to myself. If anyone gets this one, I'll drop another.
 
macdoc said:
peak oil...
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Peak Oil is a Myth,

Myth: The World is Running Out of Oil (Video) (5min) (ABC News)

Oil: Never Cry Wolf—Why the Petroleum Age Is Far from over (Science, Vol. 304, No. 5674)

Despite Popular Belief, The World is Not Running Out of Oil, Scientist Says (University of Washington)
No Evidence of Precipitous Fall on Horizon for World Oil Production (Cambridge Energy Research Associates)

Oil, Oil Everywhere... (The Wall Street Journal)
Political Peak Oil (Reason)
The World Has Plenty of Oil (The Wall Street Journal)
 
Dancing David said:
Well it is more time consuming when it comes to agriculture, you have to survey the fields to determine the level of pest infestation (this is harder with the fungal problems), then there has to be a good model of when the pest infestation will effect the yeild outcome, then a cost benefit analysis is done to determine when to apply pesticides.

However this will do nothing to limit the application of fertilizer.

Yet there is a major economic benefit to not just broadcast spraying the fields on a regular basis.

Now it would be difficult to control pest on a large scale using manual methods especially when it comes to root attacks and borers.

I personally question the whole use of the BT products as it will just increase resistance to BT.

It is rather a power full chemical but the strange use of glyphosate to resistant crops is sort of interesting. It has less drift than 2-4D so while it is very damaging to local plants, it does not drift far away and damage other plants.

But I think that nothing will change the US farmer except for economics and profit.
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Their is a whole area of research needed to investigate the huge amount of anecdotal observations by farmers who have reduced the use of certain fertilizers, substituted with various carbon sources (composts, humic acids) and concentrated on soil nutrient ratios (Ca:Mg, K:P) and found that pest and disease problems have diminished drastically.
These farmers also use refractometers to check the Brix levels in leaves, stems and fruits.
They know from experience that if the levels fall below a certain amount depending on crop, that they need to take action otherwise the crops are vulnerable to disease or pests.
The actions include foliar sprays of chelated nutrients for easy uptake directly through the leaves.
Obviously they take into account weather conditions and stage of the crop.

The theory around the reduction in disease incident revolves around the concept iatrogenic diseases
http://en.wikipedia.org/wiki/Iatrogenic_disease

A few possibilities exist.

If one plots the graph of size vs time an annual plant grown from seed with well made compost, then you get an exponential curve.
The plant starts off growing slowly and then accelerates over time.
The reason for this is that cell division is more prominent in the early stages and in the later stages all the new cells then start to increase in size slowly.
If one then fertilizers with highly soluble fertilizers and repeats the experiment, the growth curve is linear.
What happens is that the newly formed cells tend to start increasing in size sooner and faster and this evens out the curve to a straight line.
What this implies is that the cell walls of the new cells have not had a chance to thicken up gradually and you have a balloon effect.
This make the plants softer and they are easier for insects and fungi to penetrate.
This explains why developing shorter wheat and rice varieties were important for the "Green Revolution" otherwise the excessive fertilization would result in the plants lodging due to weaker stems.
The interesting thing about this all is that I have managed to "grow in" golf greens from seed till their first cutting within the same amount of time (6 weeks) using compost, bokashi(http://en.wikipedia.org/wiki/Bokashi_composting), vermicasts and compost teas as the regular way with artificial fertilizers (equivalent 10tons/hectare !!!).
Unlike the conditions when using artificial fertilizers we did not have to treat once for fungal problems.
I built 30 + of these greens more than 10 years ago 18 of which are on the only "links" course in South Africa.
We maintained the greens for a further 6 months only using compost teas, no fungicides.
The problems started when we handed over the greens to the company with the contract to manage them further and they were not prepared to think further than 2 days in advance!!
The compost teas took 2 days to brew in machines we designed and sold.
So you had to plan 2 to 3 days ahead.
This was too much for the crew of the new management and they reverted to laziness, knee-jerk reactions, crises management, blind follow the leader and plan old ignorance.
These traits are perfectly suited to the strong medicine arsenal sold by petro-chemical companies.

Another interesting possible side effect of using artificial fertilizers is the effect on a.acid synthesis.
Amino acid synthesis is dependent on carbon from photosynthesis which is limited by photo respiration amongst other factors such as water, solar radiation.
However soluble nitrogen moves into the plant with the transpiration stream and is not limited, meaning that one can get a build up of nitrogen (in the form of nitrate or ammonia) in plant cells and vascular tissue if there is not sufficient carbon and/or energy to manufacture amino acids.
These nitrates and ammonia are attractive food sources for bacteria and fungi and they will colonize plant tissues when these molecules are freely available.
 
BenBurch said:
There are limits to the efficiency of a steam engine, and even MORE limits to the efficiency of a MAINTAINABLE steam engine.

First, a non-fixed plant steam engine is rarely going to be the Watt cycle, with a condenser, but will exhaust steam to the air. It will use that steam to create a draft which helps somewhat.

You can make sure the steam is very dry with a superheater, and that helps some, and is not a HUGE burden of maintenance if you design it right, but is increased first cost.

You can have a compound steam engine in which steam is expanded once in a high pressure cylinder and again in a low pressure cylinder, but even very cost-averse railroads found that compound engines were much less effective that superheaters.

If you CAN manage to have a condensing superheated compound engine and with modern materials not have it be a maintenance nightmare, you should get 25% efficiency.

A saturated-steam single expansion Stephenson type engine will be (including boiler) around 10% if competently designed and maintained.
Click to expand...

Sounds like electricity generation would be the best, then distribution. (Even on smaller grids.)

:)
 
Poptech said:
And are 100 years obsolete!
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Because of the high energy ratio in gasoline. It stores a great deal of energy per volume. Other than that it can be used to drive steam as well, there is no real benefit to internal comubustion. It was a design choice, not a superior method.

But obsolete is a silly use of the term.
 
Let's try to keep at least vaguely near the topic, shall we?
Replying to this modbox in thread will be off topic  Posted By: Cuddles
 
Retrieved this from the binning

When the Soviet Union fell Cuba was forced to go cold turkey on fossil input for agriculture and it was a painful transition but finally a successful one.

Had the drought in the Caribbean and high temperatures continued even for a few more months a good portion of eastern Cuba would have been baked to a lifeless desert.

As it was some areas were and regions were down to 3 months of water in the reservoirs.
I've travelled widely and I've never seen an area hit so hard - cactus were dead.....EVERYTHING was dead on on the eastern tip - vultures were drinking from leaking water pipes.
I cut my arm in a fall and walked into the water to wash it off....it was like walking into a hot bath....not a warm bath a hot one. 6 months of 18 degrees would kill every shallow water reef on the planet.

Now that was localized destruction but it was indicative of what even a few years of above normal heat and low rainfail can do quickly

They got by without oil. Not without difficulty.

Even a relatively minor but long lasting heat anomaly ( 3 years )...a very different story. Nothing was grown....all was dead.
 
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macdoc said:
...

Had the drought in the Caribbean and high temperatures continued even for a few more months a good portion of eastern Cuba would have been baked to a lifeless desert.
...
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Great example.

That part of Cuba is an example of an already-tropical place that was nearly wiped out by a heat event.

One normally thinks of the Caribbean as WET. In Key West, the forecast is almost always the same; Partly sunny with an 80% chance of rain. But it does not take much to change that picture.
 
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