Quit throwing away money – get an energy audit
July 27, 2013
A consultant told me about a client that continued using practices that were wasting money and not increasing profits. Out of frustration, she asked the client for any change in his pockets. He forked over several coins worth slightly over two dollars. She picked out one coin and tossed it as far as she could. Then she picked out another coin and tossed it in another direction. At this point the client asked her what she was doing. She replied, "The same thing that you are doing." He objected saying that he does not throw money away. "Yes you do," she replied. "You're throwing money away every day that you keep doing the wasteful practices we've talked about."
Using inefficient practices and not using energy efficient equipment can be some of the ways that dairy producers or managers waste energy and throw away potential profits. An energy audit by a trained and certified farm energy auditor can help you identify practices and equipment that are wasting energy. Data presented in farm energy audit training organized by The Minnesota Project indicated that dairy farms use about 3.5 to 4.5 kWh of electricity per hundredweight of milk produced. Electrical energy costs can be roughly $120 per cow per year.
The Minnesota Project is a non-profit organization that champions sustainable production and equitable distribution of energy and food in Minnesota communities. They have organized Farm Energy Auditor Training sessions in 2011 and 2013. Successful graduates of the program are qualified to perform farm energy audits in accordance with ANSI/ASABE Standard 612. Energy audits done using Standard 612 can qualify producers and business owners for local, state and federal energy conservation programs. Standard 612 is used by USDA as the official standard for audits submitted with applications to its energy efficiency programs.
An energy audit is a systematic examination and assessment of a dairy operation's equipment and energy use data. With the farm owner's permission, a well-trained auditor will obtain at least one year of gas and electric use records from the farm's utility suppliers. An auditor will also conduct a thorough farm visit to identify and inventory equipment that uses energy. The audit should develop a list of all electrical motors on ventilating and air mixing fans, milk, vacuum, water and manure pumps, compressors, feed augers and conveyors. The audit will list equipment and estimate energy used for heating water for feeding calves, laundering towels used during milking preparation and pasteurizing milk for calves. Energy used for cooling milk with water pre-coolers and refrigeration heat recovery units is noted too. Additional essential data includes the amount of water used for cleaning the bulk tank and other milking equipment and the hot water temperature. A lighting inventory is also conducted throughout the operation to assess light levels and estimate the amount of energy used for lighting based on the equipment used and the estimated amount of time that the lights are on.
With the information collected and energy calculating software, farm energy auditors can assess energy use and identify potential ways or equipment to save energy. Good auditors will look for cost sharing programs through local utilities or conservation programs. They also estimate the return on investment or the time for the energy savings to repay for the amount of money invested in new equipment.
Some commonly recommended energy saving equipment for dairy farms includes:
- Refrigeration heat recovery units that capture waste heat from the refrigeration unit to pre-heat water for hot water uses.
- Well-water cooled pre-cooler units that use a heat exchange and well-water to cool milk before it enters a refrigerated storage tank.
- Scroll type refrigeration compressors that are more energy efficient than reciprocating compressors.
- Variable frequency drives on vacuum pump motors can slow down vacuum pumps to maintain proper vacuum levels needed for milking and speed up to provide the vacuum needed during cleaning.
- Variable speed milk pumps are used with pre-coolers to match the milk flow rate with the well-water flow rate to obtain more milk pre-cooling.
- High efficiency water heaters with greater than 90% thermal efficiency.
- Fluorescent or light emitting diode (LED) lighting that replace incandescent lights.
Producers interested in conducting their own audit can visit www.ruralenergy.wisc.edu. This is a website for assessing energy conservation on a dairy farm.
Dairy producers interested in finding a trained farm energy auditor are encouraged to visit the Minnesota Project website at www.mnproject.org. An experienced auditor can help by digging into the details necessary to ferret out potential energy savings practices. A good audit can provide owners and managers with information to decide if energy savings practices and equipment make sense for them. An energy audit will help you stop throwing money away every minute that your inefficient equipment is running.
Learn more about dairy farm energy audits at the Summer Dairy Field Day to be held August 28, 9:30 a.m. to noon at the Gary Hoffman farm, 9500 Hwy 30 SE, Chatfield, MN.