Data centres are facilities in which computer equipment such as servers, storage systems and power supplies are stored. Data centres can be in-house, used by one company and as small as a simple rack of a few servers, or can be huge facilities serving many thousands of users.
Historically, most data centres were contained within ‘server rooms’ inside the same building that they were used, but it is increasingly common for companies to utilise off-site data centres which are managed as a separate facility. Large data centres are commonly used to provide backup and other services to a large number of users. The largest data centres can have a power consumption that is comparable to that of a small town and so pollution, use of finite resources and other environmental considerations are obviously a matter for concern.
The rise of cloud computing, in which data and programs are stored in a separate physical location and accessed through the internet, have created an increasing demand for more large data centres throughout the world. As well as ensuring that data centres provide sufficient protection for security of data and environmental controls to ensure hardware runs efficiently, it is also an important to ensure that their impact on the environment is minimised as much as possible.
Energy use of data centres
Running a large number of computer systems, along with hardware to control temperature and humidity and monitoring equipment, obviously requires a lot of power. The Climate Group on behalf of the Global eSustainability Initiative estimated that the ICT sector is responsible for 2% of global carbon emissions, with 14% of this being attributed to data centres.
Energy efficiency is therefore a major concern when building a data centre and large corporations such as Google and Yahoo! have published energy efficiency goals which they aim to meet and improve as technological advances are made.
However the main issue of power use in data centres is due to the fact that they are always switched on. Usually clients of data centres demand close to 100% uptime and therefore servers must be running 24/7, whether they are providing computing power or simply idling.
Green data centres
As awareness about the energy use of large data centres is rising, efforts are being made to reduce their energy consumption. Designing more energy efficient hardware is one way to reduce energy usage, along with ensuring that buildings are designed using environmentally friendly building practices.
One simple way for data centres to save energy is by building them in physically cold parts of the world. Around half of the energy used by a data centre is spent on keeping the equipment cool, so by locating data centres in cool climates, there is a large potential energy saving.
Another way that data centres have tried to reduce their impact on the environment is by using renewable energy sources. Countries with a lot of renewable energy sources such as wind or solar power, are now favoured locations for constructing new data centres. Apple’s new flagship data centre in North Carolina is powered by 100% renewable energy, utilising bio-gas fuel cells and purchasing wind and solar power from other electricity grids. The facility has also reduced its energy usage by incorporating systems such as cold water and air flow cooling.
Is cloud computing environmentally friendly?
Cloud computing is often thought of as a greener solution than traditional systems where everything is hosted in-house. However, it’s clear that due to the energy consumption of the massive data centres utilised by cloud computing services, it is not enough simply to move computing requirements off-site.
Green data centres with the highest energy efficiency are becoming increasingly popular as companies look to reduce their carbon emissions and reduce their impact on the environment. As with any service industry, it is important for consumers to vote with their feet and actively seek out services that use renewable energy sources and incorporate other environmentally friendly practices.
An efficient cloud based computing service will use a small number of optimised servers, that are utilised close to their full capacity, rather than spreading the load inefficiently across many more machines. A report issued by Google claims that an 85% reduction in carbon emissions per user can be attained by switching to their cloud-based Google Apps system.
Cloud computing clearly has the potential to make computing a greener business, as users invest in service providers that have the resources and technology available to research and invest into greener working practices. It is certainly possible for the energy usage of a company to be reduced by huge percentages when they switch over to a cloud computing service. The responsibility lies with the cloud service providers to invest in more efficient technology and in the users to value energy efficient systems and environmentally friendly policies over services running at full capacity any hour of the day or night.
