Farm Energy Audits

The first step towards sound operation and maintenance management:

	Working with your local power utility on a farm energy audit is one of the most important first steps to take in understanding how to manage energy more efficiently. Photo: Karl Ohm

On the surface, utility costs may seem small in comparison to feed and other items associated with dairy farming; however, if left unchecked, using energy inefficiently or unwisely generates unnecessary costs that can quickly add up and impact your bottom line.

Dairy farms in Wisconsin typically spend an average of $62 to $96 per cow per year on energy (2003), which includes electricity, natural gas, LP gas and heating oil, according to the University of Wisconsin-Extension.

In 2003, dairy producers in the state spent an average of slightly more than $8,574 – or about $101 per head (2004) – on utilities. Expressed in another way, this equates into about .38 cents per hundredweight (cwt.) of milk.

According to estimates, electricity alone accounts for 2 to 5% of a dairy farm's production costs. This translates to annual electricity use of 700 to 900 kilowatt-hours (kWh) per cow or 3.5 to 4.5 kWh per cwt. of milk produced.

Utility Costs versus Farm Size

But since each dairy farm may face different circumstances, it is very important to start with an energy audit that can help provide a snapshot view of your current situation.

The farm energy audit will serve as a meaningful reference point upon which better decisions and comparisons can be made about equipment upgrades and wiring issues and what changes may offer the quickest paybacks.

Such paybacks will obviously occur more quickly in those key areas that normally use the most energy on your dairy farm.

On most dairy farms in Wisconsin, milk cooling accounts for the lion’s share of electricity usage at 25%, followed by ventilation at 19%, water heating at 18%, vacuum pumps at 17%, and lighting at 15%. Electric space heating and miscellaneous uses accounted for another 6% of electricity usage. (2)

Dairy farms in other states also show similar energy demands. For example, according to the Dairy Farm Energy Audit Summary in New York, milk cooling, lighting, ventilation, and vacuum pumps are the top four categories that accounted for 88% of all electrical energy used on all of the audited farms.

Breaking this down further, milk cooling’s share totaled 25%, followed by lighting at 24%, ventilation at 22%, and vacuum pumps at 17%. Electric water heating (4%), manure handling (4%), feeding equipment (3%), and miscellaneous (1%) made up the balance of 12%.

So, an energy audit is well worth the effort since experience has already shown that dairy producers can save 10 to 40% – or more, in some cases – by using reliable energy-efficient technology in their milking, milk cooling, and water heating processes, according to the University of Wisconsin - Madison.

 “Getting an energy audit done on your farm is an important first step to take in developing a comprehensive energy management plan,” says Scott Sanford, senior outreach specialist with the University of Wisconsin’s Rural Energy Program.

	The proper sizing of barn fans and well-functioning louvers may also be included in a comprehensive farm energy audit plan. Photo: Karl Ohm

An energy audit will help lead the way to better management, and the best place to start is to contact your power utility or the Wisconsin Focus on Energy program (Appendix).

The energy audit may also help pinpoint other areas requiring attention. For example, vacuum pumps not maintained properly, poor lighting conditions, or improperly sized ventilation fans are just a few factors that can influence cow comfort and behavior and ultimately milk production.

So, while these costs don’t directly show up as line items on the utility bill, sooner or later they will creep in and shrink your margins.

Also, many energy management recommendations made by these audits are often linked to rebates or low interest loan programs within the Wisconsin Focus on Energy program or your local utility, according to Rich Hasselman, an energy consultant with GDS Associates, of Madison, a firm that helps perform audits for this program.

CAUTION
Before attempting to do any cleaning, maintenance or inspections, make sure to read and review all safety precautions, including the operator’s manual, that may have come with the electrical equipment. When in doubt about proper maintenance and/or cleaning procedures as well as safety measures, contact a qualified electrician or your utility representative.