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.

Communications Challenges

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 Benefits

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.