Electric Fence

Electric Fence

Image: LeJay "pendulum" style fence charger
http://www.pssurvival.com/PS/Electronic/Lejay_Manual_Electrical_5thed_1945_1988.pdf

Manual has electric fence controllers and windmill-generator-battery contraptions.

Ford Model T Trembler Coil
https://www.youtube.com/watch?v=tPTmSHjSu0A

LeJay Fence Charger Made From Model T Buzz Coil
https://www.youtube.com/watch?v=vBBHuJiSY6c

How To - High Voltage from Model T "Buzz Coil"
https://www.youtube.com/watch?v=4aeb125R5QE

New Zealand innovation – improved electrical components and materials

During the late 1930s, emerging public safety issues and concerns about the newly emerging electric fences were considered at length, and began to be controlled more by regulations. In the 1960s, a different New Zealand inventor named Dough Phillips patented a new type of design using capacitor discharge, thus extending the feasible deign length of the fence and at the same time reducing its cost. This was duly patented using plastic insulators for flexibility and durability (instead of the previous porcelain) and similar systems continue to be used in agricultural electric fences today. Early fence charging devices used alternating current (AC) with a transformer and a mechanically operated switch, giving long pulses and sometimes of unpredictable voltages. As might be expected, these mechanical switches frequently failed, so later systems made use of solid state (transistor) circuitry instead of manual switching components. For a period, some types of fence energisers gave longer outputs. Nicknamed ‘weed burners’, this variant became known for causing fires in hot, dry weather and it was for this reason that their popularity reduced.
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The early development of the modern, pulsed electric fence commenced in New Zealand in 1936 when William "Bill" Gallagher built a primitive energiser from a cars' ignition coil to keep his horse off his car. This was soon extended to a fence and progressed from there. These early fence charging devices used alternating current (AC) with a transformer and a mechanically operated switch, giving long pulses and sometimes delivered unpredictable voltages. As might be expected, these mechanical switches frequently failed and the development of using capacitors and solid state circuits by another New Zealander, Doughy Phillips, greatly improved the efficiency of the system. These were generally known as "weed burners" as they tended to burn weed growth but did cause fires on occasions.
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Further modern developments: ropes and insulators

Over recent years, there have been some significant improvements including polyethylene insulators, which last longer and are cheaper, along with the electrical design of the energizing units which are also called a fencer or energiser. Modern fence chargers use low impedance circuitry, in which a capacitor is charged by a solid-state circuit. If an animal (or a person) comes into contact with the fence, the charge is released by a thyristor. This is an electronic component which can be thought of as an automatic switch so the voltage is more controlled, and the shock pulse is much shorter – typically just a few milliseconds. Fences can be powered by batteries and solar panels; if a fence is in good condition, such batteries can last many weeks depending on fence length. Woven rope-like material containing conducting wires has also been developed. Electric fences are used primarily to stop livestock from escaping or from wandering onto farmland and damaging crops. Although the majority of electric fences today are used for animal control in this way, other applications include prisons, military bases and other protected installations. Here, the aim is to maintain security, or to stop people crossing a borderline or other physical limit. The voltage delivered can be varied and may be selected to cause discomfort or in security applications, incapacitating or lethal. Finally, probably due to their intrinsic risks, there have also been legislative changes and regulations in some countries regarding the construction and use of electric fences.

https://en.wikipedia.org/wiki/Electric_fence
http://www.farmcareuk.com/blog/history-electric-fencing/
https://www.agrisellex.co.uk/blog/history-of-electric-fencing-1832-to-2016/831
https://www.smokstak.com/forum/showthread.php?t=95985 .

EU Agriculture

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24-2-1 Farmers STORM the EU - Why? - EU Made SIMPLE > .

Fertilizers

.Managing Sulfur For Your Crops - AgPhD > .

22-2-6 Decarbonising Ammonia production. Revolutionary new process - Just > .

.Fritz Haber - Nobel Laureate Who Killed Millions and Saved Billions - Veritasium > .

Growing plants need at least 16 nutrients to be healthy.

• Primary nutrients are nitrogen, phosphorus and potassium, known by the chemical symbols of N, P and K.
• Secondary nutrients are calcium, magnesium and sulfur.
• Micronutrients include boron, chlorine, copper, iron, manganese, molybdenum and zinc.
• Other nutrients that are easily available in the environment include carbon, hydrogen and oxygen. These last three do not need to be supplied by fertilizers.

Haber–Bosch process ..

Throughout the 19th century the demand for nitrates and ammonia for use as fertilizers and industrial feedstocks had been steadily increasing. The main source was mining niter deposits. At the beginning of the 20th century it was being predicted that these reserves could not satisfy future demands and research into new potential sources of ammonia became more important. The obvious source was atmospheric nitrogen (N2), comprising nearly 80% of the air, however N2 is exceptionally stable and will not readily react with other chemicals. Converting N2 into ammonia posed a challenge for chemists globally.

Ammonia was first manufactured using the Haber process on an industrial scale in 1913 in BASF's Oppau plant in Germany, reaching 20 tonnes per day the following year. During WW1, the production of munitions required large amounts of nitrate. The Allies had access to large sodium nitrate deposits in Chile (Chile saltpetre) controlled by British companies. Germany had no such resources, so the Haber process proved essential to the German war effort. Synthetic ammonia from the Haber process was used for the production of nitric acid, a precursor to the nitrates used in explosives.


Bones as Resource ..


During the war, nitrogen was one of the prime components of TNT and other high explosives. Post-war, munitions plants produced ammonia for fertilizer. Fertilizer use increased, partly due to enhanced supply and partly because farmers and agricultural scientists understood the importance of nutrients to crops.

Guano (bird droppings) became a popular fertilizer by 1800s. Trial and error experiments, first by farmers, later by scientists established the effectiveness of early fertilizers.

By the 1940s, plant scientists at universities and research facilities had determined the 16 essential ingredients for plant growth. The three primary nutrients—nitrogen, phosphorus and potassium—were needed in quantities approaching the millions of tons by 1940.

In the early part of the 20th Century, potassium was mined from potash deposits, the largest of which were in Germany. By 1940, new sources had been discovered in Canada, and there were chemical processes coming on line to supply potassium.

By 1940, phosphorus was also being produced by chemical processes and by mining phosphate rock. In the 1940s, the use of "normal superphosphate" fertilizers peaked. In later decades, it was replaced by triple superphosphate and ammonium phosphates.

Nitrogen production was boosted by WW2 developments. Nitrogen is, of course, one of the main ingredients in explosives. 

During the 1940s, most of the ammonia was applied as solid ammonium nitrate pellets. But this form is highly explosive. In fact, ammonium nitrate mixed with fuel oil is a common explosive still used in mines. There were several disasters where the material exploded in ships or other transports.

By the mid 40s, researchers were exploring ways to apply anhydrous ammonia directly into the soil. It won't explode, but it has to be kept under pressure and usually refrigerated. It can "burn" skin by drying it severely, and it can crowd out oxygen in a closed area and even cause death by asphyxiation. But, anhydrous ammonia has the highest nutrient content of any fertilizer. It's 82.5 percent nitrogen.

https://livinghistoryfarm.org/farminginthe40s/crops_04.html .

Food - Importing vs Exporting Nations

Agricultural Futures - 21st C ..

Agricultural Geopolitics ..

Farming & Food - tb >> .

Haber–Bosch process

How the Earth's Population Exploded > .

22-2-6 Decarbonising Ammonia production. Revolutionary new process - Just > .

.Fritz Haber - Nobel Laureate Who Killed Millions and Saved Billions - Veritasium > .

The Haber process, also called the Haber–Bosch process, is an artificial nitrogen fixation process and is the main industrial procedure for the production of ammonia today. It is named after its inventors, the German chemists Fritz Haber and Carl Bosch, who developed it in the first decade of the 20th century. The process converts atmospheric nitrogen (N2) to ammonia(NH3) by a reaction with hydrogen (H2) using a metal catalyst under high temperatures and pressures:

${\displaystyle \underbrace {{\ce {N2 + 3H2}}} _{\Delta H^{\circ }=0\,\mathrm {kJ} }{\ce {->}}\underbrace {{\ce {2NH3}}} _{\Delta H^{\circ }=-91.8\,\mathrm {kJ\cdot mol^{-1}} }}$

Before the development of the Haber process, ammonia had been difficult to produce on an industrial scale, with early methods such as the Birkeland–Eyde process and Frank–Caro process all being highly inefficient.

Although the Haber process is mainly used to produce fertilizer today, during WW1 it provided Germany with a source of ammonia for the production of explosives, compensating for the Allied Powers' trade blockade on Chilean saltpeter.

Throughout the 19th century the demand for nitrates and ammonia for use as fertilizers and industrial feedstocks had been steadily increasing. The main source was mining niter deposits. At the beginning of the 20th century it was being predicted that these reserves could not satisfy future demands and research into new potential sources of ammonia became more important. The obvious source was atmospheric nitrogen (N2), comprising nearly 80% of the air, however N2 is exceptionally stable and will not readily react with other chemicals. Converting N2 into ammonia posed a challenge for chemists globally.

Haber, with his assistant Robert Le Rossignol, developed the high-pressure devices and catalysts needed to demonstrate the Haber process at laboratory scale. They demonstrated their process in the summer of 1909 by producing ammonia from air, drop by drop, at the rate of about 125 ml (4 US fl oz) per hour. The process was purchased by the German chemical company BASF, which assigned Carl Bosch the task of scaling up Haber's tabletop machine to industrial-level production. He succeeded in 1910. Haber and Bosch were later awarded Nobel prizes, in 1918 and 1931 respectively, for their work in overcoming the chemical and engineering problems of large-scale, continuous-flow, high-pressure technology.

Ammonia was first manufactured using the Haber process on an industrial scale in 1913 in BASF's Oppau plant in Germany, reaching 20 tonnes per day the following year. During World War I, the production of munitions required large amounts of nitrate. The Allies had access to large sodium nitrate deposits in Chile (Chile saltpetre) controlled by British companies. Germany had no such resources, so the Haber process proved essential to the German war effort. Synthetic ammonia from the Haber process was used for the production of nitric acid, a precursor to the nitrates used in explosives.

....

The Haber process now produces 450 million tonnes of nitrogen fertilizer per year, mostly in the form of anhydrous ammonia, ammonium nitrate, and urea. Three to five percent of the world's natural gas production is consumed in the Haber process (around 1–2% of the world's energy supply). In combination with pesticides, these fertilizers have quadrupled the productivity of agricultural land:

With average crop yields remaining at the 1900 level the crop harvest in the year 2000 would have required nearly four times more land and the cultivated area would have claimed nearly half of all ice-free continents, rather than under 15% of the total land area that is required today.

Due to its dramatic impact on the human ability to grow food, the Haber process served as the "detonator of the population explosion", enabling the global populationto increase from 1.6 billion in 1900 to 7.7 billion by November 2018. Nearly 50% of the nitrogen found in human tissues originated from the Haber-Bosch process. Since nitrogen use efficiency is typically less than 50%, farm runoff from heavy use of fixed industrial nitrogen disrupts biological habitats. The Haber-Bosch process is one of the largest contributors to a buildup of Reactive nitrogen in the biosphere, causing an anthropogenic disruption to the Nitrogen cycle.
https://www.youtube.com/watch?v=U7l8imwtMkY