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An introduction to computers and computer systems
An introduction to computers and computer systems

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2 Green computing

An image of a green circuit board.

Green computing is the environmentally responsible and eco-friendly use of computers and their resources. It is concerned with all aspects of computing: the design, manufacturing and disposing of hardware; software and hardware that is designed to be run efficiently to cut down on processing power; and working practices. Though there is a growing focus on the energy needed to power the ever-increasing number of computers.

Some understanding of computing’s energy consumption can be found in the 2017 report ‘Clicking Clean: Who is Winning the Race to Build a Green Internet’ [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] which was produced by Greenpeace. Here is their take on the comparative demands of different areas of the IT sector in 2012 and in 2017.

Two pie charts, one labelled 2012 and the other labelled 2017. The first pie chart indicates that in 2012, the percentages of electricity consumption for the IT sector were as follows: Devices 47%, Networks 20%, Data centres 15%, Manufacturing 18%. The second pie chart indicates that in 2017, the percentages of electricity consumption for the IT sector were as follows: Devices 34%, Networks 29%, Data centres 21%, Manufacturing 16%.
Figure 1 Main components of electricity consumption for the IT sector.

Figure 1 shows that within the IT sector, the fraction of energy consumed by individual devices is less in 2017 than 2012, as is the fraction of energy used to manufacture IT hardware. However, the percentage of energy consumed by data centres and networks is greater in 2017 than 2012. We can’t be sure that this is as a result of the move to making more us of online services hosted in data centres, but it seems reasonable to assume that this is an important factor. The report also points out that the IT sector accounted for 7% of global electricity demand in 2012, but could be as high as 12% in 2017.

Activity 2

Find the current figures for the power consumption of computers and computer systems. Compare them with these historic figures.

Have the trends between 2012 and 2017 continued? Has the proportion of energy spent on manufacture continued to decline, while the proportion of energy consume by data centres continued to increase?

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It is assumed that even if individual computers are more efficient, because there are more computers, the overall demand for energy has increased. Is this right?

Have the trends in changing energy consumption between sectors continued? Would you say that they are changing at the same rate, or faster, or slower?

In the following section, you will look more closely at one aspect of green computing.