Getting to grips with soaring fuel costs Derek Casey looks at how factors such as tractor choice, tillage systems and tyre pressure impact on agri-diesel bills
AGRI-DIESEL prices are 60pc higher this spring than in 2016. This week, farmers will pay an average of €798 per thousand litres of agri diesel compared to €500 including VAT in 2016.
Farmers and particularly contractors (due to the huge amounts of fuel they use) need to be careful not to over expose themselves and run up large overdrafts just to keep pace with costs, particularly on fuel.
The key is regular cash flow; and this will be easier said than done this year given the context of a recent fodder crisis.
Silage is the big killer for diesel bills because it’s such a power hungry job.
Even a modestly sized contracting outfit can very quickly run up a fuel bill of €80,000 or €90,000.
Contractors need to have money coming in regularly to offset what is by far and away their biggest variable input cost. Farmers can usually be encouraged to pay earlier if given the incentive of cheaper rates for upfront payment.
In general, though, farmers should expect the higher fuel prices this year to be reflected
SOME OF THE VARIABLES THAT HAVE THE BIGGEST IMPACT ON FUEL CONSUMPTION ARE ALSO THE EASIEST TO MANAGE
in contractor charges.
Whether you are farming or contracting, you can only improve what you can measure in the first instance.
To this end it is worth analysing the fuel requirements for some of the more power hungry jobs like ploughing and power harrowing.
Did you know that ploughing with a four-furrow reversible plough, for example, tends to use on average 23 litres of diesel per hectare ploughed depending on the soil type?
At current prices this comes to a fuel cost per hectare ploughed of €18.40.
Equally hard on the pocket is sub-soiling, a job that many farmers do to relieve compaction caused either by poaching or machinery damage last backend.
Sub-soiling uses up about 18 litres of diesel per hectare worked — about €14.40 at current diesel prices.
If these figures are coming as a surprise to you (see table 1 below), turn it to your advantage by tightening up on fuel costs.
The beginning of spring is a good time to take stock of your fuel costs.
Some of the variables that have the biggest impact on fuel consumption are also the easiest to manage.
For example, tyre pressure selection is directly linked to excessive fuel consumption. Unnecessary use of counterweights is another fuel drain. And correct tractor and tillage system selection are two other ways of managing fuel use.
TRACTOR CHOICE
There are significant differenc- es in fuel consumption rates between tractors, and data from the OECD tractor tests allow valid comparisons to be made.
For these tests an individual tractor’s fuel use is usually measured in something called grams per kilowatt hour (g/ kWh).
Differences between tractor brands, but for tractors of similar or the same power levels can be significant, so it is worth doing your homework the next time you are on the market for a new tractor.
Obviously there are substantial cost implications for those tractors with poorer g/kWh ratings. Teagasc research has shown that, overall, the choice of tractor could easily account for fuel cost differences of up to €8/ha.
TILLAGE SYSTEMS
As regards the tillage system used, there are a number of different cultivation systems with various combinations of depth, tillage intensity, inversion and timing of operations.
At one extreme is the ploughbased system with intensive secondary cultivation, while at the other is a direct drill system with a simple minimal disturbance disc coulter.
Minimum tillage establishment systems offer considerable scope for fuel saving because the shallower cultivation requires much less energy input per hectare.
It is estimated that min-till systems have a primary cultivation energy requirement of approximately 37pc of that required by ploughing.
In addition, the overall fuel use of a min-till establishment system is just 50pc of that of conventional systems.
This can result in a fuel saving of between €12 and €15 per hectare, with additional depreciation and repair costs accruing as well.