Feature - How green is my grid?
(Editor's note: the following is a condensed version of a GridBriefing on Green IT, that was just published on 31 July.)
Climate change is one of the biggest challenges of the 21st century. Across Europe, efforts are being made to reduce energy usage and carbon emissions by 20% by the year 2020. The European Commission has identified Information and Communication technologies (ICTs) as key to accomplishing this.
It hopes to cut our carbon footprint all across the economy by harnessing technologies such as virtualization, and by investing in ICT research - which together promise to reduce energy consumption and increase our knowledge of the changing climate.
How green is our ICT?
ICT is responsible for 2% of European carbon emissions - a figure equalling that of the aviation industry - and emissions are expected to increase by 6% per year.
However, the biggest savings are unlikely to be via cuts in the ICT sector itself. Instead, by employing ICT in other aspects of our lives, we could significantly decrease our energy use and carbon output.
The European Commission reports that ICTs could reduce carbon emissions by 15% by 2020, and the amount of energy saved could outweigh the energy they consume five- or ten- fold.
By providing technological solutions, ICTs could reduce energy consumption in buildings by 17%, through savings in areas like lighting systems. ICTs could increase the efficiency of travel, reducing emissions up to 27%.
The role of distributed computing
Grid computing and virtualization can play a key role in reducing redundancy, and therefore, save energy.
Today's computers are designed to run one operating system at a time, but this can leave over 90% of their computing power unused. Instead of wasting electricity on an underused machine, virtualization allows use of this spare computing power. By creating "virtual machines," computers can run multiple operating systems and applications on the same piece of equipment, making much better use of its computing capacity.
"The most-significant step most organizations can make in moving to green IT is to implement virtualization for their Information Technology data center devices," says John Lamb of IBM, author of 'The Greening of IT.'
Similarly, virtual servers cut down the amount of computers and cooling systems needed, decreasing the amount of power used. Virtualization has already helped firms like Merrill Lynch, who now have just one server for every 18 servers used previously.
Likewise, the OpenNebula project is working towards a more eco-friendly way to place virtual machines on distributed infrastructures. Ignacio Llorente, who co-leads OpenNebula, states: "Our new consolidation scheduler software allows grid services to be dynamically consolidated on a lower number of physical resources. We can reduce the number of active physical systems and so power consumption and cooling requirements, without affecting applications or users."
Other companies, such as Mimecast, use cloud technology to reduce our collective carbon footprint. By letting companies manage and store their emails "in the cloud," Mimecast eliminated more than 8,300 power-intensive servers worldwide, saving enough energy to power more than 3,700 households in the U.S. for a year.
A greener grid?
The GREEN-NET research project designs software to help distribute computing jobs in energy-saving ways.
The GREEN-NET team measured the real-time energy consumption of 160 computational nodes belonging to the large-scale, experimental French Grid'5000 platform. They found that scheduling more jobs at quiet times, to even out demand on computing facilities, decreased energy usage by 30-35% per year - "equivalent to the consumption of a village of 600 residents over that same period of time!" commented Laurent Lefèvre, GREEN-NET's coordinator.
One of the biggest challenges facing ICT is coping with the ever-increasing power consumption of data centers, which account for roughly 3% of the world's energy consumption.
To improve efficiency, IBM and ETH Zurich (the Swiss Federal Institute of Technology) are planning to build a watercooled supercomputer, which recycles excess heat to warm nearby university buildings. The system could save up to 30 tons of CO2 per year compared with systems using current cooling technologies.
By using water as a coolant, they hope to reduce energy consumption by up to 40%. CERN is investigating a similar system.
Volunteer computing is also helping combat climate change. Climateprediction.net can test the accuracy of the world's best climate models, using volunteers' home computers. With the help of its volunteers, climateprediction.net has calculated over 40 million years of climate model data, and is giving decision-makers a better scientific understanding of how to tackle one of the biggest global problems today.