Stan Beer
Wednesday, 14 January 2009 07:24
Science -
Energy
Page 2 of 2
"A Harvard University researcher estimated that a Google
search generates something like 7 grams of CO2. Google engineers rebut
this with an estimate of 0.2 grams.
"The
science of this measurement is ‘imprecise’ but let’s put it in
perspective. A small car generates something like 100g of CO2 per
kilometre, so a Google search is equivalent to driving a small car
between 2 and 70 metres."
Regardless of the differing scales of carbon footprint, comparing the
environmental impact of the Internet to the automobile industry is not
something that gladdens the heart of Internet players.
As
Dr Hodgkinson asks: "Many people avoid using cars to minimise their CO2
footprint so, using the same logic, should we also now shun the
Internet to protect the planet?"
According to Dr Hodgkinson, the answer is a simple no.
Dr
Hodgkinson believes the solution lays in investing in more energy
efficient data centres not curbing Internet usage which he describes as
a Catch 22.
"Stifling demand for the Internet should not be seen
as a solution to Internet data centre energy consumption until we have
made more progress on at least three areas of supply-side energy
efficiency," states Dr Hodgkinson.
"The first is power usage
efficiency (PUE). The US Environmental Protection Agency’s 2007 study
revealed that the historical PUE of data centres was observed to be
around 2 – meaning that half of the energy that flows into a data
centre is wasted in such things as power conversions, cooling and
lighting before being applied to useful computing work.
State-of-the-art data centre engineering and server
consolidation/virtualisation strategies can see PUE reduce to 1.2 and
below, but this requires investment in refurbishing legacy data centres
and server farms and in new operational practices.
"The second
is the low energy proportionality of the current suite of computing
technologies. Reducing demand by 10% does not necessarily lead to a 10%
reduction in energy consumption. CPUs and RAM chips consume power even
when idle. Disk drives spin regardless of data traffic. There is a lot
of R&D underway to improve the energy proportionality of data
centres, but the reality today is that reducing demand does not
necessarily lead to lower CO2 emissions.
"The third is the often
hyped ‘green energy’ – connecting data centres to solar, wind or
geothermal power to replace coal fired generation.
"Here is the
‘Catch 22’. Robust demand is required to generate revenues to fund
investment in the more energy efficient technologies required to
actually reduce global data centre CO2 emissions. Too much hype around
the CO2 cost of Internet usage may well lead to people choosing to shun
the Internet, starving companies of the traffic-related revenues needed
to actually solve the problem."
In the meantime, Dr Hodgkinson concludes by offering a snippet of
sensible homespun advice for the environmentally conscious population
who want to mimimise their carbon footprint but don't want to join the
growing throng of proud technology luddites.
"Perhaps it’s better just to suggest that people turn their computers off when they are not being used."