Save your energy
Published May 2, 2008 at 12:07 pm · Filed under Features
According to Gartner, the analyst firm, datacentres now account for almost a quarter of all CO2 emissions due to the intensive power requirements needed to run and cool them. In the final article in his series, Eddie Partridge discusses how organisations can start reducing carbon emissions through greener datacentres.
More and more businesses are recognising the need to save energy and are developing plans to reduce their carbon footprint. Gaining control over the amount of power that a datacentre uses should be at the forefront of these strategies, as understanding where energy is wasted can have a huge impact on the size of your business’s carbon footprint.
There are a number of ways in which businesses can make their datacentres more energy-efficient, starting with a modular, scalable approach to power and cooling, which can deliver energy savings of up to 30%. The ability to add or remove components, such as racks, pdus and cooling, without bringing the whole system down means that at any time you only pay for what you need. A further benefit of a modular approach is that the datacentre can grow without impacting the efficiency and operation of the business.
Virtualisation
Virtualisation is another increasingly popular strategy. Consolidating applications onto fewer servers, typically blade servers, can save time, money and energy (up to 40%) while enabling a business to achieve more with its existing computer hardware.
The conservation charity WWF, for example, has cut the energy consumption of its UK server environment by more than 50% by implementing virtualisation technology. Using software from VMware, WWF moved from 13 servers to four, reducing the electricity needed to power the hardware as well as the amount of air conditioning required to cool it.*
Cooling systemsA cooling system within a datacentre should be adaptable, flexible and scalable. In-row cooling systems, such as APCs (available in both air- and water-cooled models), pump out cold air through the front and pull in hot air from the back. Datacentre hotspots ‘run less hot’ if the cooling is done by units very close to the source instead of through the ceiling or floor. Such units function autonomously, tapping temperature-monitoring leads placed directly in front of a heat source to ensure that the air remains within a specified temperature range. If a blade chassis starts running hot due to increased load, the in-row unit increases its airflow, dropping the air temperature to compensate. It also works the other way, lowering cooling activities during idle times.
Because of these benefits, it is likely that in-rack and in-row cooling will be used as the main cooling method for all datacentres by 2011.
By using leading-edge technologies such as fresh air cooling, improved efficiency in energy transfer from the street to the datacentre and virtualisation technologies, BT managed to save £3.8m in electricity costs in just nine months.**
Datacentre design
In order to mitigate hot spots occurring in the datacentre, the physical layout of the room is of paramount importance. For example, a hot aisle/cold aisle arrangement can achieve an energy saving of up to 15%. Further containment of the hot aisle can produce energy savings of up to 50-70%.
In datacentres with raised floors, clearing airway obstructions, such as redundant cables, can improve airflow dramatically, whilst providing an opportunity to locate floor vented tiles correctly for an additional energy savings of 8%.
The installation of rack blanking panels greatly improves airflow by increasing the CRAC return air temperature and reducing the mixing of hot and cold air. This reduces hot spots enabling an energy saving of up to 2% to be achieved.
Energy assessment
Ideally, each time an operational decision is made about modifying the IT infrastructure or simply increasing the amount of data storage, it will be preceded by both an energy assessment and an air flow study to identify areas of energy savings.
However, even simple actions like turning off lights in the datacentre when they are not needed or choosing the power economiser mode on a server can make significant savings to the amount of energy your datacentre uses.
Climate change is a reality, and the time has come to change the way we all think about and implement IT.
*Bryan Glick, Computing, 20 Sep 2007
**Mark Samuels, Computing Business, 22 Nov 2007
Eddie Partridge is Business Development Director of Latitude UK Ltd, one of the UK’s leading providers of single source power protection and IT Infrastructure solutions for IT and Telecom environments. Latitude UK is proactively raising awareness of greener IT solutions through seminars and by demonstrating its eco structure datacentre.
http://www.latitudeuk.com/ 01793 421 800
