The movement toward implementing a Smart Grid system across the globe means that homes will eventually need a home-area network (HAN) so the smart energy meter can measure and control energy usage. The HAN will be a separate network from the network that currently supplies the connectivity from a broadband Internet service to multiple PCs around the home and in some cases to the TV set.
Wi-Fi, the 2.4-GHz wireless local-area network (WLAN) technology, dominates the home network market right now. But it doesn’t appear to be part of the HAN effort, though it could be. Instead, the wireless HAN potential may be met by some wireless technology that begins with the letter Z—ZigBee and Z-Wave.
ZigBee seems to be leading the pack. Based on the IEEE 802.15.4 standard, this short-range wireless technology adds a remarkable software stack that implements mesh networks and a wide variety of applications. Home monitoring and control is one of the most popular applications.
The ZigBee Alliance maintains and promotes the ZigBee standard. It also certifies the interoperability of products using the standard. Recently, it announced the certification of 11 new devices from five different companies using ZigBee Home Automation. There are now 28 products certified to help consumers and professional installers create smart homes that control home appliances, lighting, heating and cooling, energy use, and security.
ZigBee Home Automation provides a global wireless standard for the control of HVAC systems, power outlets, motorized devices, security, window shades, doorbells, and other devices. Product manufacturers will benefit from this standardized approach, which makes devices reliable, affordable, easy to install, and operate.
Products using ZigBee Home Automation are ideal for new construction, do-it-yourself, and retrofit markets. ZigBee is the main wireless link from Advanced Metering Infrastructure (AMI) energy meters to the home thermostat and other devices to be monitored and controlled for improved energy management.
According to ABI Research, home automation system shipments will approach 2.8 million in 2011 as standards-based mainstream home automation systems and home automation as a service expand rapidly in 2010. New standards-based wireless technologies such as ZigBee mean that many mainstream home automation installations are decreasing in price, while the segment is further driven by the growing availability of peripheral components.
ZigBee also sponsors a Smart Energy effort that offers utilities and energy service providers secure, easy-to-use wireless HANs for managing energy. Smart Energy gives these groups and their customers the power to directly communicate with thermostats and other smart appliances. Now utilities and energy service providers can easily implement energy management and efficiency programs to meet changing government requirements.
The ZigBee Alliance and the HomePlug Alliance have been working to define a wired and wireless version of Smart Energy. HomePlug is the popular ac powerline networking technology that is an alternative to wireless and the just approved ITU G.hn wired home networking standard.
A document describing ZigBee+HomePlug is now available for download from the ZigBee Web site. It details the next generation of functionality envisioned for the Smart Grid with accompanying consumer control. Also, it includes insight into a variety of use cases including plug-in electric vehicle (PEV) charging, installation, configuration, firmware download for HAN devices, prepay services, user information and messaging, load control, demand response, and common information and application profile interfaces for wired and wireless HANs.
Z-Wave, another company vying for the HAN, focuses on the home network and has a full line of wireless modules and monitor and control products. It uses the 908.42-MHz frequency in the U.S., so it’s immune from interference with the many products using the 2.4-GHz band (Wi-Fi, Bluetooth, cordless phones, ZigBee). At that lower frequency, the range is also generally greater than that achieved in the 2.4-GHz band. Z-Wave is a mesh network technology as well. The company sells its products through Radio Shack, Lowe’s, and Fry’s.
The Z-Wave standard is maintained and supported by the Z-Wave Alliance, which is a consortium of companies making Z-Wave-based products. There are now more than 350 certified Z-Wave products.