Pumps & Systems, December 2008
A Nashville-based hunting club required the flooding of several acres of land. A shallow area approximately 1.5-ft deep needed to be flooded to help attract wild game.
Flooding the land had previously involved driving a tractor to the shore of a nearby river, and connecting a PTO (Power-Take-Off) driven shaft to a rice pump. The pump would then transfer water from the river to the fields. The tractor, which used off-road diesel fuel, was consuming approximately 5 gallons of fuel per hour at a cost of $3 per gallon.
Michael Jackson, vice president for Tennessee Process Pumps (Chattanooga, Tenn.), explained: "Because the club was flooding such a large area, it takes quite some time and can be very expensive. It became imperative for the club to minimize their energy costs." The whole process requires three weeks at the beginning of each season, with the pump running 24/7 to flood the fields. An additional two to three weeks of operation is required throughout the season to keep the acreage flooded.
In 2007, Tennessee Process Pumps proposed a solution to its customer: a 50-hp 10-in self-priming pump and an Emotron variable frequency drive. The VFD was built into a ventilated NEMA 4 enclosure that included inline circuit breakers, rain hoods, a thermostat and a cooling system. The entire package was then permanently mounted onto a 10-ft x 6-ft double axel trailer rated for 3,500-lbs. The system was installed at the club's facility in October 2007.
The complete package consisting of a pump and control panel permanently mounted on a trailer and was available in a variety of configurations.
The VFD provided the customer with the ability to vary the speed of the motor and provided complete pump protection. The particular VFD in the system offered a unique, built-in shaft power monitor. This monitoring protection has served the club well, providing protection against dry-run and deadhead conditions.
With the new setup, the supply can be altered as the demand increases or decreases. Under normal conditions, the club's new pump operates at 1,150-rpm and pumps 3,000-gpm. Using the VFD can cut these totals to 650-rpm at 1,000-gpm.
As a result of installing the new unit, the club can now flood the fields for far less money. Using the old PTO-driven setup with the tractor and rice pump, the amount of diesel fuel used by the club exceeded $15,000 annually. With the new system, there are no more diesel fuel expenses and the club now spends about $3 per hour (less than $1,500 per year) on electricity-a savings of more than $14,000 annually.
Utilizing the new pump and VFD system, the club is now confident that its fields will be filled as inexpensively and as efficiently as possible.
For more information about Emotron variable frequency drives, call 866-663-9060. For more information about Tennessee Process Pumps' "Baby Huey" series pumps, please call 423-266-8404