Energy Saving Tips for Irrigators

[jba...@gmail.com]

Most irrigation systems are not as efficient as they should be. A
Kansas study found that, on average, irrigation systems use about 40
percent more fuel than they would when properly sized, adjusted, and
maintained. (Black and Rogers, 1993) A study in Colorado, Wyoming,
Nebraska, and other states found that, on average, about 25 percent of
the electrical energy used for irrigation pumping was wasted due to
poor pump and motor efficiency. (Loftis and Miles, 2004)

Efficiency audits conducted by NCAT on more than 400 irrigation
systems identified, in the vast majority of cases, at least one
equipment change or repair that would have quickly paid for itself in
energy savings alone. Very often, the irrigators who owned these
inefficient systems were unaware of any problems.

A publication on ATTRA offers some good solutions to the problem:

ENERGY SAVING TIPS FOR IRRIGATORS:

This publication describes ways to save energy and reduce irrigation
energy costs. There are basically four ways to do this:

* Make mechanical improvements, so the irrigation system uses less
energy during each hour it runs.

* Make management changes, so the system runs fewer hours.

* Reduce cost per unit of energy by, for example, negotiating a better
rate with the utility, switching fuels, or finding a lower price for
diesel fuel.

* Make your own energy by installing a wind turbine to generate
electricity or by making your own biodiesel fuel, for example.

This publication focuses on mechanical improvements. Of course, good
management is also critically important for saving energy. The most
obvious energy-saving management strategy is to eliminate unnecessary
watering, meeting only the water needs of your crops. But you might
also consider less obvious options such as changing to less water-
intensive crops, timing plantings to take better advantage of natural
precipitation, reducing irrigated acreage, using mulches and cover
cropping to increase soil organic matter and build the water-holding
capacity of your soils, or taking steps (such as planting wind breaks)
to reduce evaporation in your fields.

Equipment problems and management problems tend to go hand in hand.
Equipment that is badly designed, inefficient, or poorly maintained
reduces the irrigator's degree of control over the way water is
applied. Problems like patchy water distribution and inadequate
pressure make it impossible to maintain correct soil moisture levels,
leading to crop stress, reduced yields, wasted water, runoff, soil
erosion, and many other problems.

On the other hand, mechanical improvements do not necessarily result
in energy savings, unless the irrigator makes management changes that
reduce hours of operation. (See Hanson, 2002) This is a key point that
is frequently misunderstood. Mechanical improvements like the ones
described in this article generally improve irrigation system
performance, resulting in higher pressure and increased volumes of
applied water. These improvements in turn should make it possible to
meet crop water needs with fewer hours of irrigation. But if the
irrigator continues to run the system for the same number of hours,
energy consumption often stays the same or even increases.

read more >>

http://attra.ncat.org/attra-pub/energytips_irrig.html

John
jba...@gmail.com