Northwest Iowa Power Cooperative (NIPCO; Le Mars, Iowa, U.S.) is a rural electric cooperative supplying power to western Iowa. To control the 850 miles (1368 km) of transmission line in its service territory, NIPCO uses a supervisory control and data acquisition (SCADA) system manufactured by Open Systems International (www.osii.com).

The control system is comprised of five networked servers and five workstations providing a graphical interface using dual or quad displays. Through a man-machine interface, the SCADA system controls the NIPCO power grid. The servers and workstations are located away from the power-dispatching area, where the control and monitoring of the power grid actually takes place. This arrangement keeps the key components of the SCADA system in a dry, cool and clean environment.

In the past, standard keyboard, video and mouse (KVM) extenders provided the link between the workstations in controlled environmental chambers and the dispatching work area. This worked to distance the components, but the KVM extenders were subject to induced magnetic fields and interference regularly. It usually found its way into the shielded and unshielded Category 5 cables between the KVM extender end units. The source for the interference was found to be from flickering florescent lights; motors starting and stopping; radio-frequency interference; lighting dimmer switches; and differences in ground rise potential between the two rooms. In such a controlled environment, even small moves of any of the cables under the computer floor could cause the KVM switch to lock up or system instability to occur. If that happened, the KVM switch needed to be reset, or the Cat-5 cable needed to be moved to a different location to minimize the induced electrical noise or interference.

To eliminate these issues, NIPCO selected the Matrox (www.matrox.com) Extio F1400 remote graphics unit. Extio leverages PCI Express bus-extension technology to separate the I/O devices from the computer and drives multiple displays from the monitoring location. With Extio's support for multimode fiber-optic cable, the NIPCO control system is impervious to the challenges of the wired system.

Once installed, the Extio F1400 unit worked immediately, and the quality of graphics improved considerably on the video displays. Even the projection map board showed marked improvement in resolution and sharpness. NIPCO's control operators record and chart system power flows on multiple monitors, and one Extio unit per operator system supplied video to all four monitors with superb resolution.

With the success of the Extio rollout, the cooperative has decided to incorporate Extio F1400 into its energy management system as well. This EMS is leveraged several times monthly when the demand for electricity energy is at its highest.

Through this technology, NIPCO is able to defer that load for several hours, reducing the cost of electricity to the end consumer.