Going Green: Vampire Devices and Zigbee

The xchange magazine article titled Telecom's 40 Shades of Green that I referenced on Wednesday includes a small section on "vampire devices". Vampire devices (also referred to as parasitic devices) do not have off switches and include products like DVD players, recorders and game systems. Have you ever walked around your house at night, counted the number of LEDs glowing in the dark and thought about the amount of power they were sucking up? Wouldn't it be great if you could turn some of them off and save a little power? It may not be just a "little power" - the U.S. Department of Energy estimates 5% of all electricity used in the U.S. is consumed by devices in standby mode and predicts this will increase to 20% by 2010!

One technology that has some energy saving potential is Zigbee. Zigbee is a Wireless Personal Area Network (WPAN) technology based on the Institute of Electrical and Electronics Engineers(IEEE) 802.15 specification. Zigbee operates at 868 MHz, 902-928 MHz, and 2.4 GHz and allows devices to communicate up to around 50 meters away at up to 250 Kbps. Zigbee was designed to maximize power - battery powered devices using Zigbee can sleep for hours or days. According to the Zigbee Alliance, ZigBee is the only wireless standards-based technology:

- that addresses the unique needs of remote monitoring & control, and sensory network applications.
- that enables broad-based deployment of wireless networks with low cost, low power solutions.
- that provides the ability to run for years on inexpensive primary batteries for a typical monitoring application.

The ZigBee 1.0 specification was ratified in December 2004 and we are starting to see Zigbee products come to market. Greenswitch, a wireless energy control system company, has a good video clip from Ed Begley, Jr's show Living with Ed posted here. In the clip Ed describes how the Greenswitch's Zigbee system can be used to control light switches, wall sockets, air conditioning, heating, etc systems. You'll also find 6 short videos on the Greenswitch site describing a step by step home Zigbee system installation.

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Update, 12/18/07:
Mike Q sent along a link to a great Vampire Energy diagram that estimates how much energy is being comsumed by common devices when they are in standby mode. Here's the link: http://awesome.goodmagazine.com/transparency/008/trans008vampireenergy.html

Thanks Mike!

Going Green: Metcalfe's Law and the Enernet

Bob Metcalfe, the inventor of Ethernet, founder of 3Com and now with Polaris Venture Partners is interviewed by Tara Seals in the December 2007 issue of xchange magazine in an excellent article titled Telecom's 40 Shades of Green. In the article Metcalfe describes what he calls the Enernet, a standardized, networked web for the distribution of energy, much as the Internet distributes information.

Seals refers to Metcalfe’s Law in the article, which Metcalfe first used to describe Ethernet systems, and discusses how it applies to alternative energy systems using sources like solar, wind or bio-fuel. Here's a quote from the article describing Metcalfe's law:

Metcalfe’s Law says that the value of a telecom network is proportional to the square of the number of users of the system; the more distributed users there are on the system, the greater the value of the network and of those endpoints themselves. In other words, it describes a blueprint for an explosion of growth, and explains many networking phenomena we have today, from the Web to social networking. Standards+Metcalfe’s Law = efficient, sustainable, viral, organic networking growth.

Solis Energy is mentioned early in the article - you've probably seen Solis or Solis-like solar generators driving along highways or along airport runways. The companies Solar Power Plant (SPP) series are designed for low wattage telecommunications devices like wireless access points, cameras and security systems. Equipment can be powered directly by 12, 24 or 48 volts DC, by Power over Ethernet (POE) or inverter supplied AC. The company claims, with the right product selection, continuous power for 7 days without sunlight. There are also Simple Network Management Protocol (SNMP) modules for Solis SPPs that allow status monitoring of temperature, battery, load and photo-voltaic power.

On a much larger scale, Google has installed the largest corporate panel solar panel installation in the U.S. at the Mountain View, CA Googleplex. To date. 9,212 solar panels have been installed on eight buildings and two carports. The system installation company, EI Solutions, has a great fly-over video linked here. Additional panels will be installed to complete the 1,600 kilowatt project. Google has a site up on the web (linked here) that charts energy production for the project.