August 02, 2010
Utilities are busily crafting plans to add some smarts to their grids, which will enable them to monitor usage information in real time. For these new capabilities to take shape, they will need networks capable of moving information from their data centers to customer sites.
Wireless communications are appealing because they are easier to deploy and less expensive than wired connections. Long Term Evolution (LTE) cellular, Wi-Fi and WiMAX wireless options could fill this void, but recently WiMAX has emerged as the most likely selection.
Wireless communications have become popular recently because they now offer sufficient bandwidth to support a variety of applications. In addition, they fit nicely with utilities' smart grid plans because many have already been using low-bandwidth, wireless links to collect information from their meters. Another plus is that going wireless means energy companies do not have to run wiring to customers' homes, a process that can be time consuming, labor intensive and difficult to maintain.
So which wireless option should they select? Wi-Fi has proven to be quite popular for connecting laptops to networks and is inexpensive, costing a few dollars for a chipset. "Wi-Fi does not have sufficient range to be used in the smart grid," said Judith McGarry, vice president of marketing at Grid Net, a startup focused on delivering smart grid software. Wi-Fi was designed to transmit information only a few hundred feet. It can be used to cover broader distances but that step involves stationing access points close to one another, which drives up the deployment costs.
LTE cellular has garnered a great deal of support from carriers, such as AT&T and Verizon. However, its ecosystem is in a nascent stage of development. Few LTE products are now shipping, and the first commercial deployments began at the end of 2009. Perhaps because of its immaturity, the suppliers have shown little interest in promoting the technology in energy markets.
WiMAX has been in development since the turn of the millennium when telecommunications carriers started to search for a robust, high-bandwidth, wireless networking option. From its inception, this networking technique was built to support wide-area network (WAN) connections, although it is flexible enough to work with end-user devices. A wide-area network covers a large geographic area that is usually hundreds of miles.
The technology evolved slowly but recently has started to generate steam. A few hundred vendors now offer WiMAX products, and since early 2008, cellular network suppliers such as Comcast, Sprint, and Time Warner Cable have been rolling out WiMAX networks.
The technology has been carving out a small but growing niche in the smart grid. For instance, GE Energy has developed WiMAX smart meters, which are being used in several pilot programs. The vendor teamed with Grid Net on one deployment with Australian utility SP AusNET. "Australia is an interesting market because it is already deregulated and utilities are aggressively rolling out smart grids," said Grid Net's McGarry. By 2013, the network will monitor electricity usage for more than 680,000 customers in Victoria.
Some Issues
In the United States, GE has been installing its WiMAX MDS Mercury 3650 radios to link CenterPoint Energy's wide-area network to customer energy system collection points. The utility, which serves the Houston area, has installed more than 267,000 smart meters and expects to deploy more than 2 million smart meters by 2012. The company received $200 million in federal stimulus funds to help move the project along.
San Diego Gas and Electric is also jumping on the WiMAX train. The utility has deployed about 130,000 smart meters so far and plans to increase that number to 1.4 million wireless smart meters in its 4,100-square-miles service area. Federal funding is providing $28.1 million of the $60 million needed to build out its WiMAX network. In addition, Southern California Edison and National Grid are reported to be dabbling with WiMAX as part of their smart grid initiatives.
However, WiMAX is not a panacea. Currently, a chipset costs more than 10 times as much as Wi-Fi. "WiMAX pricing has been dropping so one can find chipsets selling for less than $10," stated Ashish Sharma, vice president of marketing at Alvarion, a WiMAX equipment vendor. Currently, not many utility-specific devices exist and work remains before WiMAX connections can be quickly deployed and easily managed.
However, none of these obstacles seem insurmountable. In fact at the moment, WiMAX seems to be further along than competitive technologies trying to gain a foothold in the smart grid, so it may eventually become a de facto smart grid standard.
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Paul Korzeniowski
