Earlier this month, GE officially endorsed ZigBee as the wireless standard of choice for smart appliances in a white paper, but the Wi-Fi guys aren’t having any of it.
The Wi-Fi Alliance released a statement yesterday denouncing the white paper as “flawed” and “inaccurate.” Though their response isn’t exactly a surprise, their counterargument merit a look.
First, the Wi-Fi Alliance argues that GE’s test of power consumption used an older protocol of ZigBee (Smart Energy Profile 1.0) that lacks the security and IP communications required for smart grid use. The alliance also took issue with the study’s use of the 802.11b chip, which it says is based on decade-old Wi-Fi technology; it argues that Wi-Fi based on the newer 802.11n standard would have yielded better and more realistic results since it’s the one currently used in real-life smart grid rollouts. Finally, the statement pointed to what it said was a more comprehensive study by the Association of Home Appliances Manufacturers (AHAM) that ruled in Wi-Fi’s favor.
Update: The back-and-forth continues — Zigbee’s spokeswoman emailed to say that the AHAM study didn’t only rule in Wi-Fi’s favor, but also singled out ZigBee as one of the top performers in its test. (HomePlug Green Phy was also in the top).
A spokeswoman for the ZigBee Alliance responded to Wi-Fi’s salvos with a statement pointing out the use of ZigBee in about 40 million smart meters to date, as well as the technology’s ability to “securely transfer data at very low power rates.” She added, “There are more than 100 — and growing — competitively priced ZigBee Certified products available today, all of which are made by different companies who performed their own due diligence before creating a product.”
It is a high-stakes fight for relevance in what will be a big and important pie. Pike Research estimates that the smart-grid services market will be worth $4.3 billion by 2015, and Zyprme estimated the smart grid market at $21 billion last year and forecast that it will double to nearly $43 billion by 2014. Although GE is just one customer in the smart grid market, it is a behemoth and leads as an aggressive player in smart appliances and an investor in cleantech ventures. The issue seems to mirror the protocol war in the smart grid, where cellular networks, proprietary networks and the WiMax standard continue to battle for adoption, with no hands-down clear winner yet evident.
It’s also not entirely clear who to believe in this battle. GE has already integrated ZigBee into many of its home appliances, Greentech Media notes.
The GE paper tested the two technologies via custom firmware and found that ZigBee consumed less power in a 24-hour period than Wi-Fi, with Wi-Fi having a larger baseline power consumption (chart from the paper is pictured, right). It also found that ZigBee’s simple processors were $11 cheaper than its Wi-Fi counterparts and argued that ZigBee’s mesh network topology was superior to Wi-Fi’s star network topology. The paper was authored by the folks at GE’s Appliances & Lighting division, and looked at ZigBee, Wi-Fi and Bluetooth for home area networking for smart appliances. Bluetooth was dismissed for its limited range and its star network configuration, which relies on devices connected to a central hub, as opposed to mesh networking, where each device can act as a node.
This was evidently the same hangup GE’s writers had for Wi-Fi. While the paper notes that both ZigBee and Wi-Fi “can meet data performance needs,” it argues that ZigBee’s mesh network topology is better for reliability and ability to communicate and that it also allows some devices to remain in sleep mode while other parts of the network are active.
Both sides have made their case. What do you think?
[Top image via Army.mil]
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