Peak oil demands and declining oil reserves, increased greenhouse emissions and global warming

and economic drivers for operational and cost efficiencies promote energy efficiency as one of the

most important global issues. Meeting the demands of an expanding world population is becoming

increasingly difficult not only as the global climate changes but as further limits are placed on water,

land, energy and other resources. Rising energy costs are particularly acute for agriculture, which

relies on energy intensive process to produce necessary fertilisers and chemicals. Because cotton is

a highly mechanised and high-input crop which relies on diesel, fertilisers, chemicals, water and land,

meeting the energy challenge is particularly important to Australian cotton production.

Energy efficiency is an important consideration for agriculture both in terms of rising energy costs.

Australia’s electricity prices have increased by 80% in the last 5 years, which has far exceeded the

increases in consumer price index changes in the same period. It is projected that electricity prices in

Australia will further increase by another 30% in the next 2 years. Hence, there is increased

importance in quantifying energy use, as a step toward encouraging efficient energy use on the

farm.

The CRDC has previously funded the NCEA to conduct a desktop study of on-farm energy use for a

number of case study cotton farms to understand the range, costs and contributions of energy use

to cotton production and greenhouse gas emissions. The results from this work showed that energy

use varies depending on the cropping enterprise and the farming system and that there are

significant opportunities to reduce energy and costs. While direct on-farm energy use is a small

component of the total energy used in the production of cotton lint, any savings made flow directly

to the grower. The largest energy consumption in field to factory production of finished lint is the fertilisers used in cotton production, which is the on-farm indirect energy use shown in figure 3,

below.

A more detailed study undertaken by the NCEA on a large cotton farm in the Gwydir Valley identified

significant reductions in energy resulting from the adoption of reduced tillage systems. The study

showed that the adoption of a minimum tillage system had reduced energy costs (and greenhouse

emissions) by 12% since 2000 and developing a “near zero till” system had the potential to reduce

this to 24% less than 2000 energy costs.

It is evident from this work that there is substantial scope to improve energy use efficiency in cotton

production systems, but to enable more growers to identify where they can improve, further

development of tools, processes and human capacity is required.

Energy efficiency may be one of the fastest, cheapest and easiest ways to cut farmers energy

expenditure and greenhouse gas emissions. Measuring or estimating energy use across an

enterprise is the most important first step in this process because it identifies the major energy

consuming operations across the enterprise and hence defines where the largest gains may be

made. This same process can be used to assess the net worth of any changes.