PUE - Power Utilization Effectiveness - is a common measure of energy efficiency for ICT facilities. We have often cited it in our articles, but we are mindful that efficiency does not necessarily lead to sustainability. Here are some areas where PUE can fall short.

Several companies have been working to create cloud computing volume servers using "wimpy chips". These are low-power, lower-speed chips designed for mobile devices. The idea is that large numbers of these in a server can yield lower energy consumption while maintaining cost-effective performance. Most recently, the EU has launched an initiative using the wimpy-chip approach.

Our e-gear contains many exotic materials. We've looked a how the demand for some - "conflict minerals" - fuels bloody, long-term warfare. The mining of others pollutes local communities. The rare earth neodymium, used in everything from smartphone speakers to datacenter disk drives, is a case in point.

Green-certified computer displays are now too numerous to list in table format. Here are where to find them:

Belching diesel equipment is not what one imagines when visualizing the Internet and mobile communications. It turns out they play a significant role in ICT's consumption of fossil fuels and emission of GHG.

We've identified almost 17 billion edge devices attached to our global ICT infrastructure. It turns out that the United States has a wide range of recycling rates for the different categories of e-gear. Which is best and which is worst?

We've added newer rankings for mobile and smart phones, but left the original ones below for those looking to reuse an older unit.

Green ICT is concerned with all resources consumed in creating e-gear and operating ICT infrastructures. Significant amounts of water are used in everything from chip fabrication to PC manufacture to data center operation. This makes ICT vulnerable to droughts and other water constraints.

Handling our gear's heat has always been an issue for installations large and small. ICT equipment typical took 1x-2x again more energy to remove its heat as it took to power it in the first place (PUE of 2.0+), driving both energy costs and carbon footprints. Early efforts focused on the two obvious tactics: make both the gear and the air conditioning more efficient. We now see these augmented by innovative new approaches to the problem.

The Pacific Island Schools Connectivity, Education, and Solar (PISCES) Project has installed a Solar-in-a-Box kit as a computer lab at a primary school on the island of Udot in the Federated States of Micronesia. The installation illustrates several ways in which Green ICT technologies and practices can deliver ICT to remote areas.