Integrating Remotely Located Substations Into SCADA Systems: A Case Study Using Commercially Available Satellite Internet Service Providers for SCADA Communications

This paper presents observations and analysis experienced by a utility end user. As SCADA systems become a crucial part of daily operations for utilities, finding low-cost, reliable communications for substations in remote geographic locations often presents a challenge. Current SCADA communications methods, including framerelay, T1, and fiber are often unreasonably expensive, in terms of installation costs and length of service contracts. Consequently, this can make integrating a utility’s entire system into a SCADA network economically unfeasible or difficult to justify. In an effort to overcome these obstacles, Plumas-Sierra Rural Electric Cooperative (PSREC) recently installed redundant, commercially available satellite Internet connections, from two separate providers, at two of its substations. These satellite Internet connections serve as redundant communications paths for the substations and enable their integration into the SCADA system. This paper discusses the architecture, security, implementation, results, and lessons learned from installing commercial satellite Internet services as a means of communications for SCADA systems, as well as the economic reality of using such a service over typical, more common SCADA communications methods.