Optimising use of power in datacentres is a high priority for datacentre managers, but they continue to face challenges as power becomes a larger percentage of ongoing datacentre costs. In fact, Gartner estimates that ongoing power costs are increasing at least 10% per year due to cost per kilowatt-hour increases and underlying demand, especially for high power density servers.
Approximately 10% of datacentre operating expenditure is power, and power is likely to be about 15% of datacentre opex within five years.
In most cases, improving IT equipment power usage can result in the greatest overall improvement in power usage efficiency. The power usage effectiveness metric has become a de-facto industry standard for measuring how efficiently a datacentre uses energy. However, according to Henrique Cecci, Research Director at Gartner, although the power usage effectiveness metric focuses on the datacentre energy efficiency of the facilities’ components, it does not provide insights into energy efficiency improvements at the IT equipment level.
“In most cases, improving IT equipment power usage can result in the greatest overall improvement in power usage efficiency,” says Cecci. “There are five key steps datacentre managers should follow in sequence to maximise efficiency, as well as a Step 0 for measuring and monitoring power usage, so that improvements can be monitored along the way.”
These five steps include:
Optimising IT power
Since IT systems are what ultimately require power delivery, datacentre managers need to try to lower the amount of power to IT equipment, known as payload power, that is required. 60% of the payload power is consumed by servers so taking the following actions to reduce the power they require is crucial.
- Consolidate virtual machines
- Virtualise more workloads
- Replace old servers with newer ones
- Continue to eliminate servers that are powered but doing nothing useful
- Clean up workloads and eliminate everything that is not necessary
Optimising datacentre space
Datacentres built before the advent of server virtualisation may be overbuilt for today’s equipment needs, enabling further reduction of the necessary space for IT equipment and less IT power. When building a new datacentre, it is worth considering a modular design that breaks down the datacentre into individual modules that can be continually refreshed as part of a more flexible and organic datacentre design.
Optimising datacentre cooling
In order to achieve a minimum level of efficiency, datacentre managers should ensure the adoption of basic datacentre cooling best practices.
Install economisers
In cooler regions, an air-economiser can significantly improve the power usage effectiveness. In most of North America, for example, 40% to 90% of the cooling can come from outside by using air economisers.
Contain equipment and heat
Isolation structures can house the datacentre equipment generating the most heat and funnel the heat out of the datacentre or to heat other parts of the building.
Optimise air conditioning systems
There are two primary ways to optimise an air conditioning system, turn it off periodically, using an alternative cooling source, such an air optimiser or to continually vary the speed, which helps to reduce the total amount of energy the unit consumes.
Eliminating datacentre power and cooling inefficiencies
Outdated power delivery systems, including uninterruptible power supplies, power distribution units, and transformers, can negatively impact power usage effectiveness ratios. Evaluating the current situation, future requirements and modern alternatives require time and investments, but typically generate a good return in terms of power usage effectiveness ratio improvement and savings.
Utilising DCIM tools
Further refinements to energy efficiency can be achieved through the use of datacentre infrastructure management software. DCIM software provides the necessary link between the operational needs of the physical IT equipment and the physical facilities, building and environment controls.
“Approximately 10% of datacentre operating expenditure is power and power is likely to be 15% of datacentre opex within five years”
“In most cases improving IT equipment power usage can result in the greatest overall improvement in power usage efficiency”
“In order to achieve a minimum level of efficiency datacentre managers should ensure the adoption of basic datacentre cooling best practices”
Gartner contributor Christy Pettey presents various options that datacentre managers can follow to curb rising energy costs.
