Blue Ridge EMC now has the ability to provide Internet protocol-based communications services.
Blue Ridge Electric Membership Corp. is responsible for providing energy to an area encompassing four counties in northwestern North Carolina, most of which is located in the Appalachian Mountain range. As demand for the advantages of the smart grid has increased — particularly automated meter reading (AMR) with its potential for significant savings both to the utility and its members — the need to provide reliable Internet protocol (IP)-based communications services remains strong.
Because the northwestern part of the state is predominantly rural and has a challenging terrain, options for communications services are limited. For example, mountainous terrain does not easily accommodate wireless broadband IP communications, a solution often used in flatter geographies for building out communications networks. A challenge for Blue Ridge EMC is to provide communications to remote locations at a reasonable cost.
Bringing AMI to Members
An additional push for upgrading the communications system came in 2007, when Blue Ridge made the decision to install Aclara's Two-Way Automatic Communications System (TWACS) technology. The AMR/automated metering infrastructure (AMI) system enables Blue Ridge to remotely read electric meters daily, and even hourly, so members can manage their power usage. The project should be completed by the end of 2010.
The TWACS AMR system allows Blue Ridge to reduce the number of meter readers deployed, thus reducing budgets for salary and benefits, and lower its vehicle costs because fewer are needed to travel from site to site. This system was extremely valuable in the winter of 2009-2010, given the record amounts of snow and ice the Blue Ridge area experienced. During the months of January, February and March, inclement weather rendered some of the utility's more-remote locations inaccessible by vehicle.
The AMI system also allows the district to offer a Flexpay program, through which members can choose to make prepayment arrangements instead of paying a large deposit to have service connected. The service can be remotely connected or disconnected as needed.
In addition to other growth demands on the region, AMI added to the urgency of building out a robust communications system.
Since the early 1980s, Blue Ridge has owned and operated a microwave radio network to provide interoffice communications between district and corporate offices. While the microwave network has been reliable and provided adequate service, it could not meet the utility's needs as demand for higher-speed data increased. When considering alternatives, the district had to evaluate how to meet the following objectives in the best and most cost-effective manner:
Provide greater bandwidth for IP communications to each office
Bring IP to substations to take advantage of increasingly prevalent intelligent electronic devices (IEDs)
Accommodate the large amount of meter-reading data from distribution substations to the corporate office as the new AMI deployment was realized
Use the new communications system to help stimulate economic growth in this rural area.
After performing a path study of the major substations, Blue Ridge engineers knew it would be too expensive to build enough microwave sites to provide broadband communications to each station. Earlier conversations with the only telephone co-op in the region also had proven fruitless; leasing services from them to meet Blue Ridge's communications needs would be too costly. A fiber-optic network seemed the most feasible alternative.
In 2001, when Blue Ridge was planning the first phase of its fiber network, a wireless communications company indicated interest in leasing dark fiber capacity as it was deployed. A subsequent contract with the company allowed Blue Ridge to offset some of the costs of deploying fiber. The initial deployment involved laying 8 miles to 10 miles (13 km to 16 km) of fiber, which has expanded to 120 miles (193 km) today. The full build-out is expected to be completed by 2012.
The fiber deployment allows even the most distant substations to be linked securely to corporate IT, using the utility's gigabit fiber network. Some of these substations were defined as critical cyber assets, and all applicable North American Electric Corporation (NERC) critical infrastructure protection (CIP) security standards are being implemented. Following NERC security standards makes good sense, because the more secure the networks are, the more reliable they will be.
Fiber connectivity at substations is the logical choice for backhauling meter-reading data to the corporate office. The Blue Ridge corporate office is now able to implement weekly billing, and it will be able to implement billing at a daily level should that option be judged beneficial. The engineering department has data readily available for load analysis, for example, load trending and more-accurate predictions regarding the need for and timing of system improvements. Where IEDs have been installed, engineers can analyze fault data, and the dispatchers in the operations center can ping individual meters to determine exactly where an outage has occurred.
During the fiber build-out, Blue Ridge evaluated several alternatives for connecting the more-remote substations. Dial-up lines proved too expensive, with long-distance billings of US$2000 to $3000 per month being the norm. Where the terrain permitted, the utility installed Ethernet radio equipment at substations to relay information to the corporate network. When the terrain made radio transmission impossible, Blue Ridge chose digital subscriber line (DSL) circuits from local telephone companies for backhaul operations, as they are both less expensive and faster than dial-up connections.
Network Equipment Requirements
The Blue Ridge telecom/IT team defined a list of requirements to be used when evaluating equipment to be deployed as the network is upgraded. First, equipment needed to be hardened to withstand the electrical and environmental extremes found in substations. Second, the new equipment had to be compatible with the existing network equipment. Third, the new equipment had to meet today's NERC CIP requirements and be flexible enough to support anticipated future directions. Fourth, the equipment had to be easily monitored and managed remotely.
After evaluating several products, Blue Ridge chose security gateways made by Astaro Corp. and Magnum 6K managed switches from GarrettCom for deployment in most of its substations. Where fiber has been deployed, it is connected directly to the Magnum switch at the substation. To securely transmit information over the DSL lines, the security gateways act as a firewall between the substation network and the Internet.
The network switching equipment protects the substation network and transmits data over a separate DSL line to the corporate office. All unused ports on the Magnum switches are disabled to further enhance security. Fiber offers the advantage of being able to deploy multiple virtual local area networks (VLANs) to segregate engineering applications and corporate Ethernet traffic. DSL does not support VLANs; therefore, it works best in distribution stations that have minimal transmission equipment.
Supervisory control and data acquisition (SCADA) remains on a separate wireless network that is not IP based. The network, which was deployed almost three decades ago, provides the required services reliably. By keeping SCADA separate from engineering and corporate data, the utility can leverage past investments while ensuring the IP infrastructure is in place for the eventual migration of the SCADA system, when it becomes necessary.
Deploying an IP communications network to substations throughout the Blue Ridge EMC territory is an expensive endeavor, but the benefits derived make it worth the investment. The ability to get real-time data from substations, read meters remotely, and download historical and event data from IEDs are just a few of the benefits.
In addition to achieving a level of efficiency, the goal is to provide reliable and affordable electric service to northwestern North Carolina. The new system has allowed Blue Ridge EMC to partner with other carriers and telecom service providers to fulfill an additional corporate mission of helping stimulate economic growth in the region.
Mike Lowe (firstname.lastname@example.org) is fiber/communications manager at Blue Ridge Electric Membership Corp., where has worked for more than 30 years. He is a member of the board of directors and member services division chair of the Utilities Telecom Council, based in Washington, D.C. He earned his associate degree in electrical engineering from Catawba Valley Technical Institute in North Carolina.
Companies mentioned in the article:
Blue Ridge EMC www.blueridgeemc.com
GarrettCom nc. www.garrettcom.com
North American Electric Corporation www.nerc.com