Data centres are notoriously power hungry. What might surprise you to learn is that the most power-hungry element of the typical data centre is not the servers at all – but the cooling systems that are needed to prevent the servers from over-heating.
In recent years, as servers have increased in capacity and speed, the amount of heat generated has increased massively. This means data centres need to work harder than ever to maintain an optimum temperature.
Data centres need to offer these high-capacity, fast servers to meet customer demand, but using this technology creates real issues around energy consumption and efficiency. First and foremost, in many cases, is the issue of cost – powering cooling systems is expensive, so anything a company can do that reduces the need for cooling has to be a good thing.
Cooling is particularly expensive in older data centres, which were not necessarily designed with efficient energy use in mind. For example, in older data centres it is common to have cooling systems for an entire room. The problem with this approach is that it creates a mixture of hot and cold air, with no directed flow – meaning heat generated by the servers is not efficiently extracted. The result is wasted energy and problems maintaining a regular temperature, which can in turn, impact on the performance of servers themselves.
In this kind of non-optimised environment, energy costs are significantly higher. For example, a dual-processor PC server might use 265 watts of electricity per hour, but cooling could add an additional 135 watts to this figure. Over four years, the energy cost of running this kind of server can reach 50% of the cost of the hardware itself.
Older data centres can also be less efficient in their basic structure. If the walls of the building offer poor insulation, then heat can pass through the walls at an alarming rate, meaning more demand for cooling, and higher energy costs.
Making Greener Energy Choices
Fortunately, the data centre industry has worked hard to develop new approaches to design and cooling that mean it is possible to significantly reduce energy consumption and improve efficiency and environmental performance.
Research shows that using these technologies, and improving the design of data centres can deliver energy savings of up to 80% over a traditional data centre.
Sources of advice and information about reducing energy waste in the data centre include The Green Grid, the Climate Neutral Group and the European Commission Code of Conduct for Data Centres. EvoSwitch works with all of these groups, and we are always looking for ways to make our technology and designs as energy efficient as possible.
The Climate Neutral Group is an environmental initiative that works with data centres and organisations on projects that help to restore the world’s CO2 balance, such as planting trees and developing new biogas projects which help to neutralise emissions in the atmosphere. These small steps all help to counteract energy emissions from data centres.
Companies can also make ‘greener’ choices when investing in new technologies. The Green Grid is a global consortium of ICT suppliers that are pushing for more efficient technologies in data centres. The Green Grid finances current and new investments in green technologies and also works to provide customers with affordable energy services.
Green energy plays an important role in generating more environmentally friendly energy. Many companies utilise green electricity from suppliers including the Delta Power Company, which generates power from sustainable energy sources, such as wind, sun and biomass.
To help businesses understand their energy consumption, the Green Grid also introduced Power Usage Effectiveness (PUE), a metric that measures the efficiency of data centres by comparing total energy consumed to the amount of energy that actually reaches the IT equipment. This process can highlight just how much energy is lost en route, through cooling, for example.
Well-designed data centres can save customers substantial amounts of energy, reducing costs. Many new data centres can obtain a PUE of 1.2, which is a massive reduction compared with traditional data centres. Over time, companies should work to reduce energy costs, save customers money, while also reducing the carbon based emissions. Using state of the art modular box environments, EvoSwitch now utilises adiabatic cooling to provide the highest energy efficiency possible to customers.
Reducing Energy Consumption
Of course, while green energy is important, it is equally important for data centres to try and conserve power, and reduce consumption.
Data centres typically need to run 24/7, but with some innovative design, it is possible to introduce small changes that make a big difference. For example, high frequency lighting (30,000Hz) with sensors that automatically switch lights off when nobody is around are a simple way to ensure power is not wasted unnecessarily.
Companies can also reduce consumption by taking advantage of some of the innovations in cooling systems. Many data centres now use cold aisle corridors, in which racks are isolated from the rest of the data hall in enclosed units to prevent a ‘short circuit’ of hot and cold air , which would result in wasted energy. By isolating the front of the servers with a roof and sliding doors at each end of the corridor, it is possible to create a fully sealed unit which allows the front of the servers to be cooled, and the cold air to be pushed through to the back of the racks to be efficiently exhausted.
The advantage of cold aisle corridors is that cold air cannot escape from the sealed unit, and is not wasted by being released into the warm air of the server room –reducing overall energy efficiency. When creating cold corridors it is possible to raise the overall ambient temperature of the data centre to as much as 22-25 degrees Celsius, without affecting the cold corridor, which reduces energy consumption even further.
In the most advanced data centres, it is also possible to take advantage of free cooling, which uses cold air from outside the data centre to chill corridors. This works particularly well in countries with cooler climates such as the Netherlands, where ambient temperatures are below 15 degrees Celsius for most of the year.
Free cooling offers a substantial cost saving over traditional cooling and is particularly valuable if companies choose to locate their data centres in locations that emphasise high quality and energy efficient hosting. Ultimately, these companies will find that centres located in such places provide high performance, extremely efficiently. The new wave of carbon-neutral data centres are working hard towards becoming consistently ‘green’ at all levels, reducing power consumption and costs, while increasing efficiency. At EvoSwitch, we implement a range of cutting-edge, green technologies that allow us to be as energy-efficient as possible, and to share the financial and environmental benefits of these investments with our customers. In the current financial and political climate, we believe only those data centres taking such steps will continue to provide the highest value for customers.
Tags: Power & Cooling, Green Tech