We've been tracking the growth in mega-datacenters since 2009. These faculties feature technical and operational innovation that has overturned previous notions of limits on energy efficiency. But does the focus on efficiency obscure an acceleration in ICT energy and water consumption and in CO2e production? While mega-data center operators are claiming exceptional power usage effectiveness (PUE) ratios, we're still talking about facilities that consume 20-200 MW apiece and emit a considerable carbon footprint unless powered by renewable energy. Here's our most recent look at their reported PUE and the technology behind them, including the addition of a government supercomputer center that highlights subtle issues of efficiency versus sustainability.

Location is becoming increasingly important to the sustainability of ICT facilities. We've been tracking facilities in North American and Europe which try to leverage geographic features for greener operations. Our latest example has Apple benefiting from its Nevada (US) site's underground water and low risk of natural disasters.

Liquid cooling was once a staple of large-scale computing, but has largely been replaced by air cooling. We identified several efforts to bring liquid cooling to the server world in our first version of this post a year and a half ago. Here is an update featuring a UK company.

Google offers frequent updates on its Green ICT progress. Here is the most recent, along with past updates.

Photos, inside and out, of Google's data centers. Note that most locations include a reference to some green initiative.

This has not been detailed on Google's useful blog, but Grist reports that "Google’s new $700 million data centers in Taiwan will make ice at night, when electricity is significantly cheaper, and use it to cool the buildings during the day."

Google announced in January 2012, "All of our U.S. owned and operated data centers have received ISO 14001…certification. We’re the first major Internet services company to gain external certification for those high standards at all of our U.S. data centers." Here are some of the specifics.

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.

Vertatique posts have covered the attraction of locations that offer renewable energy, typically a combination of hydroelectric power and free air cooling from a temperate/cold climate. But about data centers in sunny climates? The question provided a good opportunity to check in on solar photovoltaic electricity (solar PV) back in 2009.

Apple's 2012 Facilities Report provided detail on on the sustainability features, ranging from 'free air' cooling to real-time power monitoring, in Apple's Maiden (NC-USA) data center. A more recent report commits to 100% renewable energy.

A Pike Research report says that the trend to greener data centers will yield a significant GHG slowdown as well as drive a substantial market opportunity. Here are some of the top-line numbers from Pike.

Microsoft researchers have proposed that "servers can be sent to homes and office buildings and used as a primary heat source. We call this approach the Data Furnace or DF. Data Furnaces have three advantages over traditional data centers: 1) a smaller carbon footprint 2) reduced total cost of ownership per server 3) closer proximity to the users." Data centers are already being used as heating sources in Europe, 'data furnaces' takes the concept to the distributed residential level.