To achieve a more energy efficient datacentre it is important to separate each component within the datacentre and then evaluate each area to identify savings.
Right Size
Using a modular scalable approach to power and cooling presents an approximate energy saving of up to 30%, (this will vary from datacentre to datacentre). A modular approach enables you to pay only for what you need currently; this building block methodology means that components such as racks, pdu’s and cooling can be removed or added without the need to bring the whole system down.
As well as being cost-effective, a modular system means that datacentres are only creating a footprint they need at that immediate point in time but have scope and capacity to accommodate future growth without impacting the efficiency and operation of the business or wasting energy.
Virtualisation
Virtualisation has revolutionized many businesses by consolidating applications onto fewer servers, typically blade servers. The virtualisation of the infrastructure simplifies IT so companies leverage their storage, network, and computing resources to control costs and respond faster. The virtual infrastructure approach to IT management creates virtual services out of the physical IT infrastructure, enabling administrators to allocate these virtual resources quickly to the business units that need them most.
In a virtual infrastructure, users see resources as if they were dedicated to them while the administrator manages and optimizes resources globally across the enterprise. Virtualisation is a technology that can benefit anyone who uses a computer, from IT professionals and Mac enthusiasts to commercial businesses and government organisations. Virtualisation will save time, money and energy (up to 40%) while achieving more with existing computer hardware.
Architecture
In order to mitigate hot spots occurring in the datacentre, the physical layout of the room is of paramount importance. Modern designs must take into account the rise in rack densities now ranging from 8kw to in some cases 25kw or more. While a typical server in the year 2000 consumed only 100W of power, the average server today consumes at least four times as much. Combined with rising energy costs and increased server density, the growth of datacentre energy spending could far outpace the rate at which IT budgets grow, leaving less budget for other vital IT initiatives and projects.
• Gartner Group suggests energy costs may increase from 10% of the IT budget today to over 50% in the next few years
• Forrester claims servers would use about 30% of their peak electricity consumption while sitting idle
• IDC predicts the cost to power servers will exceed the cost of the servers by next year
• The US Department of Energy states that datacentre energy usage can be 100 times higher than that for a typical commercial building
• IDC calculates that the total power and cooling bill for servers in the US stands at a staggering $14 billion a year, and if the current trends persist, the bill is going to rise to $50 billion by the end of the decade.
It’s not surprising that servers built for density, particularly blades, are intensifying the problem. Stacking these servers into a small footprint requires more watts per rack and creates the potential problem of ‘hot spots’. In row cooling creates shorter air paths which require less fan power and are comparatively easy to install. A hot aisle/cold aisle arrangement can achieve an energy saving of up to 15%.
Air Conditioners
Air conditioning units that push air out through dropped ceilings or raised floors are common within datacentres. However, many air conditioners now offer economising options which can offer a substantial energy saving up to 15%. It is important to make sure that all installed air conditioners work in harmony together to optimize the efficiency of each unit and in turn reduce overall power consumption.
Floor Layout
Floor layout has a huge impact on the efficiency of the air conditioning system. Introducing a simple hot aisle/cold aisle arrangement effectively segregates warm and cold air.
Provided the air conditioners are correctly placed to effectively cool this layout then expect massive energy savings, especially if the datacentre has in-row cooling systems.
In-row cooling systems are now a popular option between racks. Cold air is pumped through the front of the rack, pulling hot air from the back. In-rack and in-row cooling is much more energy efficient and can achieve energy savings of up to 12%.
Efficient Power Equipment
Datacentres guzzle electricity which is why it is crucial to consider the energy efficiency of power equipment. For example, new UPS systems have half of the energy losses of legacy UPS equipment? Simply choosing the power economizer mode on a server makes a significant contribution to reducing energy consumption. New best-in-class UPS systems have 70% fewer losses than legacy UPS at typical loads. Light load efficiency is the key parameter, NOT the full load efficiency resulting in savings of up to 8%,
Vented tiles
For datacentres using a raised floor, locating floor vented tiles correctly could result in energy savings of up to 8%. Typically, vented tiles are located incorrectly in datacentres or the wrong number is installed. Clearing airway obstructions underfloor, such as redundant cables, can improve air flow dramatically. A professional assessment can ensure an optimal result.
Coordination
Many legacy datacentres have multiple air conditioners that actually fight each other. In row cooling has higher efficiency for high density.
CRAC supply and return temperatures are higher, increasing efficiency, capacity, and preventing dehumidification
Again a professional assessment can diagnose if the air conditioners are working efficiently with each other which could save 10%.
Lighting
Over the last few years we have become more energy conscious at home by switching off lights and using energy efficient light bulbs, but in the commercial environment lighting is sometimes overlooked as an energy saving. Using more efficient lighting technology in a datacentre results in a possible energy saving of up to 3%. Remember that lighting generates more heat, which results in air conditioners working harder to cool the datacentre. Therefore turning off lights when they are not needed could have a double impact on your energy savings.
Panels
The installation of rack blanking panels is a cost-effective solution that saves energy. Blanking panels greatly improves airflow by increasing the CRAC return air temperature and reduces the mixing of hot and cold air. The primary benefit is that hot spots are reduced and an energy saving of up to 2% can be achieved.
Ideally, each time an operational decision is made about increasing the IT infrastructure or simply increasing the amount of data storage, it should be a prerequisite that an energy assessment is carried out to identify areas of energy savings. The ten points mentioned in this article allow you to gain a valuable insight into ways in which energy can be saved; collectively they form the basis for a further in depth analysis of ways in which energy consumption can be reduced within the datacentre. As power and cooling become the primary control or limiter for datacentre growth the challenge for us all is to, conserve energy whilst increasing efficiency within the datacentre Climate change is a reality, and the time has come to change the way we all think about and implement IT, more importantly what impact will these decisions have on the huge carbon footprint that is being created by IT.
