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Traction power

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This article deals around the sources of traction power, useful for eg pulling agricultural machinery.

Sources of traction power

In general, there are 2 sources of traction power: from animals, and from machines (engine-powered). Due to the work of Fernando Funes-Monzote in Cuba [1], we know that we can reduce the energy needs as far as possible (ie a 25x reduction was noted in the documentary). However, a better balance can (possibly) be found by using more efficient machinery rather than animals. It is true that ie conventional tractors spend far too much energy compared to ie animals; however, I believe that this is due to their dimensioning. As noted in the documentary, they can not cultivate crops that are placed close together, and they are also badly designed, resulting in a huge efficiency drop. However, with better design, these downsides could be eliminated. Animals for example generate very strong greenhouse gases (methane), require allot of food vs the work they do (see the article I made at http://en.wikipedia.org/wiki/Mechanization#Mechanical_vs_human_labour ) and are also a risk regarding ie public health (they spread disease, work as a vector, ...) As such, I think it is best to eliminate their use as an agriculture instrument (aswell as their use as a food themselves) alltogether. I believe that in the very near future, they can be replaced with smaller (automated) machines. Already, there are some pruning and weeder robots (ie Ruud), and combined with well known techniques such as crop rotation, companion planting, the use of organic pesticides (see link in forwarded message below), ... they can easily be discarded.

However, besides the ecologic and economic advantages over time, there is still the issue of the primary purchase cost, which would be much higher than that of a horse. Thus, the use of draft horses, oxes, ... for now or simply as a temporary solution (until they attained the money to built a traction engine) seems advisable. (Some more research is needed; ie purchase cost small & large draft horse/ox, purchase cost AT traction engine ?) The reason why the purchase cost (and not the costs on long-term) may be less is because animals can be propogated at practically no cost at all. On the long-term however, the efficiency losses (animals consume more calories for a given task than machines) eliminate benefits attained from the reduced purchasing cost.

Animal power

Several animals can be used: draft horses, ponies, oxes, ... (lama's/camels ?) Depending on the animal chosen, cost-efficiency will increase/decrease. --> which animal is most cost-efficient ? Depending on the region, several animal breeds seem most useful: horse breeds

Cost

According to

Power rating

Finally, I also posted something at http://en.wikipedia.org/wiki/Talk:Horsepower#Horsepower_from_a_horse (despite a bit confusing, it contains some very important questions on this subject).

Machine power

Template:See One particular issue I discussed with him was that the machinery used today isn't cost-efficient, but machines in general are (if they are built appropriately). The question however is, how are they best built ? Instead of posting things on the village pump (and mailing everyone in the process), I thus want to discuss it first with you, and see whether I can then immediatelly post it on a seperate page instead (I couldn't find suitable other pages to post this on).

I was thinking that a traction engine, purpose-built (see http://en.wikipedia.org/wiki/Traction_engine ) might be suitable. However this would best not be steam-powered since the parts required for this would be quite heavy and thus result in a economically unuseful project. Potentially, either wood gas could be used, or an emissionless fuel, ... I am still thinking about this though, but it would be made lightweight and as efficient as possible (the use of lightweight, low-cost caterpillar tracks might be incorporated, perhaps based on the DFRobotshop Rover, see below).



I'm also unaware how much HP we'll require for the traction engine (older traction engines had some 2HP, or the power of 2 horses ?), but I'm unaware whether this is actually enough. In the Edwardian Farm, it was enough (although the result was not amazing), and we can even beef it up easily to 12HP (a regular lawnmower engine has 12HP), but even then I'm still not sure whether that will be enough. This as (2) horses can generate upto 30 HP (see the wikipedia talk page) atleast momentarily; so horses can actually pull out the plough if it gets stuck ie in very clayish soil, ... whereas a lawnmower-powered traction engine "may" not.

Depending on your answer we can hopefully post it somewhere at Appropedia.

What I'd like to see is some consideration of when it is suitable to use an animal, versus a tractor, with reference to both analysis and field experience. Someone must have written about making this decision, somewhere on the web? I'm sure that local people in rural areas already make the decision, and know their own context better than we can. But having some good info - and most importantly a good set of questions to consider - could be useful for project managers in development programs.