QUANTA SERVICES INC, QUANTA SERVICES MANAGEMENT ...

WiMAX backhaul communications will cause the cell relays associated with that segment to fail over to the secondary path, a public cellular carrier (AT&T)
network.
The smart grid communications model was developed as an end-to-end design with dual communications paths to provide redundancy. By implementing a
private wireless infrastructure as a primary communications path and using a public cellular carrier as the secondary path, CenterPoint was able to use the
full strengths of both types of networks to create a reliable solution. This redundancy and resiliency enables CenterPoint to live up to its brand promise:
"Always there."
Communications Network Build
Smart meters transmit electric usage data wirelessly to cell relays installed on electric distribution poles connected to both the WiMAX and cellular networks.
More than 5,200 cell relay sites have been built across Houston to communicate with the more than 2 million meters installed across CenterPoint's electric
distribution territory.
The cell relay location consists of a cell relay, a wireless WiMAX remote radio and an antenna - all of which are powered by electricity from the power line
with battery back-up. For approximately every 75 cell relay locations, there is a WiMAX radio tower site that functions as a take-out point (TOP) to collect
the data.
At the cell relay sites, communications crews program the WiMAX radio and then align the antenna to ensure the radio is communicating with the TOP. TOPs,
which are built mainly at CenterPoint substations, collect data from cell relays within a several-mile radius and deliver the data, through the microwave and
fiber backhaul network, to the data center.
The TOP consists of a 150-ft (46-m) steel lattice tower or pole. On the structure, crews installed three WiMAX antennas, spaced 120 degrees apart, to
receive signals from surrounding cell relays. In addition, crews installed and aligned the microwave dish to connect with the core network through an
adjacent microwave location. The telecommunications equipment for the TOP is sheltered inside a concrete building at the base of the tower or pole. Cell
relay data collected through one of three master radios - one for each antenna - is routed over the microwave network by fiber-optic cable to the data
center.
A data collection engine passes information collected from the cell relays to the meter data management system, which processes and stores meter data and
also executes service orders. CenterPoint sends meter data to the Smart Meter Texas web portal, where consumers may securely view their historical 15minute
usage data in 24-hour, 30-day and 13-month snapshots.
The Network Takes Shape
More than 2.2 million smart meters have been deployed, along with 5,220 cell relays and 140 TOPs. With these in place, more than 2 billion intervals of
usage data are being recorded and made available to consumers on the Internet each week.
In 2012, CenterPoint has obtained 15-minute interval data at a rate of 99.3%, along with 99.8% of monthly register reads used for billing. More than 97%
of service orders have been completed electronically, typically within 30 minutes, saving nearly 3 million truck rolls, with concomitant savings in fuel and
reduction of carbon emissions.
Considerations and Lessons Learned
The real test of a communications network is how it functions in practice. The deployment process posed its own challenges and taught some significant
lessons:
Communications network development must be closely coordinated with the meter deployment. CenterPoint's meters were deployed by route, and the
network communications infrastructure was in place and stable three months ahead of the meter deployment. This approach allowed meters to begin
communicating with the system immediately.
Be prepared to use creative design and installation solutions to meet aggressive time lines. For example, one of the tests performed at potential cell relay
sites was to determine WiMAX signal strength to the WiMAX take-out site. When signal testing to a cell relay site was needed before the take-out site towers
were built, large cranes were used to position the antennas at the appropriate height.
Complete the design of the overall communications system up front. Integrate all communications components into an overall architecture, test and analyze
all equipment, complete construction standards, identify all construction materials and validate installation procedures through testing and training.
Manage materials and multiple service suppliers closely and establish strong field coordination along with detailed construction and performance acceptance
and testing processes. Major equipment and long-lead items such as cell relays, radios, network electronics, towers and buildings need to be specified, bid
on and ordered well in advance, and inventory levels maintained in a warehouse system and tracked. Given the fast pace of deployment, inadequate
inventory can cause significant schedule disruptions.
Be prepared to support the infrastructure operationally when the first device goes into production. Identify staffing requirements and analyze, select and
implement network management tools as they are used both for construction and for connectivity testing and operations.
Leverage a common communications infrastructure. The intelligent grid network is built to leverage the advanced metering system communications
infrastructure so remote or automated switching commands are executed over the same network from which electric usage data is communicated.
Keys to Deployment Success
Page 21 of 26
An effective communications network has CenterPoint positioned for the future. The smart grid is not only the future for CenterPoint, it is the future of the
utility industry. With this in mind, the following approaches may be considered when planning any smart grid communications system:
Establish a strong governance process. A strong project management office, using a proven governance methodology, is essential to the overall success.
With the deployment of any integrated system, especially one as complex as an advanced meter system, the application of consistent scheduling, financial,
scope, change and reporting processes is imperative.
http://search.proquest.com.ezproxy.spl.org:2048/printviewfile?accountid=1135
12/6/2012