Tips on saving fuel by correct mechanisation practises
By Mr Johan van Biljon and
Dr Tingmin Yu
Problem statement
Mechanisation is necessary when doing crop production but can be very costly due to improper practices because of expensive farm machinery costs and increasing fuel prices.
It is therefore important to plan and utilize farm mechanisation systems efficiently and thus to save costs when doing farming operations. Ultimately farming business is only sustainable when it is profitable.
Importance of equipment maintenance
Proper maintenance of tractors and equipment is very important to be able to optimize fuel consumption. Timely clean and replacement of air and fuel filters can reduce fuel consumption and increase engine power. Changing oil on schedule and greasing moving parts will also help maintain tractor efficiency.
Repairing of any malfunction parts from the implements before field operation sometimes can avoid big loss due to failure in field and can always reduce fuel consumption.
There is no doubt that well-maintained tractors and implements will minimize breakages and save time and money.
Tractor to implement matching
Using a large tractor for light duty jobs is inefficient. It is important to utilize the engine capacity of the tractor because larger tractors are more expensive in total kW. Using a too small tractor for operations that need more engine power is also inefficient because the engine under overloading or too high wheel slip can lead to higher fuel consumption as well.
The illustration in Figure 1 shows some relationships between engine performance and traction parameters. As shown in the graph, when the specific fuel consumption in l/ha is at its lowest point the implement is perfectly matched to the tractor and the work rate in ha/hour is at its highest top point. This is also indicated as the most efficient wheel slip point. The graph shows another fact that a certain percentage of wheel slip is necessary for efficient traction although too much wheel slip will increase fuel consumption and decrease the work rate.
Selection of operating speed
As every operation have an optimum speed to work on, the selection of correct operating speed is important to optimize fuel consumption.
At constant load, the higher the speed, the higher the engine power required in kW. The engine specific fuel consumption is at it’s lowest when operating the engine at close to maximum power. Too fast operation speed may also lead to engine overloading and inefficient operation is resulted. Too slow operation speed may lead to under utilization of engine power or excessive wheel slip.
Gearing up and throttling back can lead to fuel savings. Make sure not to overload the engine, excessive black smoke indicates overloading.
Ballasting tractors correctly
Properly ballasted tractors with recommended tire inflation rates can improve fuel consumption and increase traction efficiency by creating the required amount of wheel slippage for the specific implement and field conditions.
A certain amount of wheel slip is necessary to create good traction as indicated previously. However, the research has revealed that the optimum average wheel slip percentage is between 10 and 15%, but may vary according to the field condition and working speed.
Optimizing efficiency of field operations
Field efficiency refers to the time the operation takes versus the turning and other non-productive time. Spending too much time turning around at short fields, or overlapping tillage operations within a field can result in higher fuel consumption. Planning for best road travel trips can also save fuel.
Precision agriculture practises
Energy and therefore a big fuel saving can be created by using global positioning guidance systems such as auto-steer with a planting operation or any other soil preparation activity.
Site-specific farming using equipment guidance, yield monitoring systems, field mapping and precision crop input applications can provide many economic and environmental benefits in addition to energy savings.
It is therefore very important to make use of precision agriculture technologies to save costs on many aspects of the farming practices, which also includes the very expensive fuel costs.
Reducing tillage practises
Conservation tillage in terms of mechanisation refers to minimum tillage or even no till which generally uses less fuel than full tillage systems because the soil is tilled less intensely and less often. These tillage practices may also allow seedbed preparation, fertilizer application, and seeding in fewer passes to reduce soil compaction. Such practises are also eligible for carbon credits in the long run.
Traffic control practises
Traffic control practises in sandy soils, for instance ripping every year on the same tracks can save fuel and energy requirements. It is therefore economically viable to practise traffic control when possible.
Conclusions
There are various aspects to take into account to be able to practise the most economic fuel saving actions on a farm by optimised mechanisation planning.
Practising fuel saving actions on your farm will not only saving you money and energy, but will also be environmental friendly.
Enjoy your farming by proactive planning.
Enquiries: vbiljonj@arc.agric.za
yut@arc.agric.za
