Tractor Design & Testing 3(2+1)

Lesson 29. Optimization of Tractor Field Efficiency to Save Energy/Fuel

1. Turning time

To reduce turning time, farmers should make fields large, long, and narrow by eliminating fence rows, ditches, or other barriers. Larger implements, if matched to tractor size, can be more field efficient because bigger implements cover larger areas and require a smaller number of turns. Long narrow fields can enhance the efficiency of field operations. The concept of “tilling off the corners” of the field when tilling diagonally can also save fuel by having the turning result in a tillage operation.

2. Wheel traffic pattern

Controlled wheel traffic patterns can save fuel and reduce total soil compaction in a field. The tractor and other machinery operate in the same tracks for all operations, improving tractive efficiency with compaction occurring only in a narrow area. Crop growth in the uncompacted areas of the field is considerably better than if some compaction occurred all over; however, poor drainage or other problems may occur near the compacted zone.

3. Conservation Tillage

Conservation tillage generally uses lesser 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. Such practices are also eligible for carbon credits.

Deeper tillage results in greater fuel use. With every inch of increase in mould board plowing depth, approximately 0.57 more liters of diesel fuel per acre is used. There is a proportionate increase for other tillage operations at increased depths. Secondary tillage should not be deeper than one-half the depth of primary tillage.

For example, if a field is plowed 8 inches deep, disking should be no deeper than 4 inches. Shallower secondary tillage has the added benefits of not only saving fuel, but reducing compaction and lessening the amount of wet soil and weed seeds brought to the soil surface. Water loss is also often reduced with shallower tillage, resulting in a longer period before first irrigation is necessary and/or better overall early plant growth.

4. Matching Implement Size to the Tractor.

Using a large tractor for light loads is inefficient because extra horsepower is used to move the larger tractor. Producers should consider using a smaller tractor if possible. On the other hand, using a smaller tractor to perform operations that require more horsepower can overload a smaller tractor, reducing its overall efficiency.

5. Selecting the Optimal Engine and Travel Speeds.

Most tractor engines have the highest fuel efficiency when operated at or near rated speed and load, or maximum power. For primary tillage implements properly matched to the tractor, the best fuel efficiency in the field is achieved by pulling loads at the fastest speed possible within the acceptable speed range for the implement. Increasing the gear and lowering the throttle speed can lead to fuel savings. Make sure to not overload the engine; excessive black smoke indicates overloading.

6. Optimizing Wheel Slippage

Some wheel slippage is needed to reduce excess wear on the tires. The optimal level is generally 10 percent, but the actual level depends on the type of tractor, the speed and the implement being used. Properly ballasted tractors with recommended tire inflation rates can improve fuel consumption and increase tractor efficiency by creating the required amount of tire slippage for the specific tractor, implement and field conditions.

7. Fuel Storage and Alternative Fuels

Proper storage can save fuel before it goes into the tractor. Keep above-ground fuel storage tanks shaded and paint them a light color to reduce the loss of fuel by evaporation. Use of biodiesel or other bio fuels will reduce reliance on petroleum products.