ZigBee standards-based wireless platform is optimized for Smart Grid remote monitoring and control applications

A power grid becomes a smart grid thanks to an advanced two-way communication system that supports realtime monitoring of current operations and the ability to respond to those conditions. For smart metering applications in homes and commercial buildings, wireless is the simplest, most cost-effective and scalable way to build out that communication infrastructure. And ZigBee technology appears to be the wireless communication protocol of choice for smart meter deployments. According to Bob Heile, chairman of the ZigBee Alliance, today’s smart energy initiatives require the systems around us to be more intelligent: sharing information, processing it and applying it to improve energy efficiency.

ZigBee is a specification for a suite of high-level communication protocols using small, low-power, wireless radios. The ZigBee Alliance, an association of more than 400 companies worldwide that define and promote the technology, states that, “ZigBee Smart Energy is the world’s leading standard for interoperable products that monitor, control, inform and automate the delivery and use of energy and water.” The standard focuses on simplicity, reliability, lowcost and low-power needs for smart energy products that are easy for utilities and governments to deploy, while also being secure and consumer-friendly.

While ZigBee has initiatives in several markets, a recent In-Stat report predicts smart energy to be the largest volume growth opportunity for ZigBee and IEE 802.15.4 (the physical radio standard on which ZigBee is based). The report predicts that ZigBee will help push chip and module shipments to exceed three quarters of a billion units by 2014.

“Energy management organizations as well as IT companies like Google are also taking an interest in helping drive ZigBee to the forefront of network adoption,” says Brian O’Rourke, In-Stat principal analyst. “Proprietary solutions still have a large share of the market, but because government measures require standards-based solutions, ZigBee stands to benefit significantly in the long run.” While Smart Energy and Smart Grid initiatives are underway worldwide, technology adoption remains a regional determination. However, ZigBee Smart Energy was selected last year by the U.S. Department of Energy and the National Institute of Standards and Technology (NIST) as an initial interoperable standard for home area network (HAN) devices. And the ZigBee Alliance is expanding its participation in the European Union’s Smart Grid standardization efforts.

ZigBee technology is well suited to energy management applications that require interoperability and the RF performance characteristics of the IEEE 802.15.4 standard. The 802.15.4 standard supports scalable, battery friendly and cost-effective designs, which makes it ideal for high-volume, low-cost smart energy applications such as smart meters, in-home displays and home appliances. Moving forward, the ZigBee Alliance has working partnerships with a wide range of industry groups, including the Internet Engineering Task Force (IETF) and the Internet Protocol for Smart Objects (IPSO) to define IP functionality for the ZigBee IP specification.

For today’s smart energy product developers, dozens of ZigBee components are available, including standard RF chips, modules and platform components that can reduce the complexity of integrating embedded RF. Popular options today are surface-mountable modules that include a fully operational transceiver, memory and microcontroller, and vendors provide software toolkits, including profile templates, to support application layer development.

For remote sensor applications, ZigBee’s low duty cycle and its ability to remain quiescent for long periods support long battery life. ZigBee was designed for hostile RF environments, with features including collision avoidance, receiver energy detection, link quality indication, clear channel assessment, acknowledgement, security, support for guaranteed time slots and packet freshness.

One of the key attributes that sets ZigBee apart from other wireless standards is its large network size. The standard supports static and dynamic star and mesh networks with 64,000 nodes per network, and multiple network coordinators can be linked together to support extremely large networks. The logical size of a ZigBee network ultimately depends on which frequency band is selected, how often each device on the network needs to communicate, and how much data loss or retransmissions can be tolerated by the application. A recent ZigBee application – the MGM ARIA resort in Las Vegas’ new City Center – will include 85,000 networked ZigBee Smart Energy devices designed by Control4 to monitor and control guest environments.

A recent report by ON World states that ZigBee has been adopted by more than 350 global manufacturers with annual revenues exceeding $1 trillion dollars. And the ZigBee Alliance recently announced that more than 100 ZigBee Certified products are now on the market, with more than 40 million ZigBee-based smart meters installed around the world.

Cheryl Berglund Coupé is Editor of EECatalog.com. Her articles have appeared in EE Times, Electronic Business, Microsoft Embedded Review and Windows Developer’s Journal and she has developed presentations for the Embedded Systems Conference and ICSPAT. She has held a variety of production, technical marketing and writing positions within technology companies and agencies in the Northwest.