These servers store data, host millions of web pages, and generally enable the miracle of modern communications. I like to think this is accomplished through the efforts of an army of hamsters exercising frantically on millions of tiny wheels. Elves are also an enticing possibility.

 

Sadly, neither hamsters nor elves are responsible for keeping the internet afloat. Instead, a vast amount of energy (non-hamster generated) is required. In the US, the energy to power data centers accounts for 1.5% of total US electricity consumption, and costs $4.5 billion every year. This enormous cost is expected to double over the next five years as the need for data centers continues to grow.

And what of the environmental impact of data centers? In 2007, data centers accounted for 14% of global greenhouse gas (GHG) emissions, and these emissions are expected to rise alongside the increasing costs of data center energy use (see Climate Group's SMART 2020 report). Any way you slice it, data centers are expensive facilities in need of serious improvements.

Fortunately, this massive energy consumption and associated GHG emissions have not gone unnoticed or unchecked. Governments are also establishing guidelines and legislation to promote energy efficiency in data centers. In February 2010, the EU, Japan and the US came to an agreement on the guiding principles of energy efficiency metrics for data centers. As international standards begin to emerge, IT companies around the world will be required to become greener. Some of the IT giants such as Google, Dell and IBM are starting to shift towards greening their data centers voluntarily, since they recognize the cost saving opportunities along with the chance to be leaders in the push to go green.

Out of these efforts, a wealth of information on best practices is beginning to take shape. The US Department of Energy's Lawrence Berkley National Laboratory (LBNL) has already spent years researching the issue of energy use in data centers, and has established 67 best practices that cover every aspect of energy use in these facilities. Since data centers typically use 15 times more energy per square foot than a regular office building, it is vital that these best practices are adopted along with any other opportunities to save energy.

One of the primary areas of inefficiency in data centers are the HVAC systems , which use between 21% and 54% of the total energy used by the building. This is largely due to the huge amount of heat produced by the servers, and the concurrent need of these same servers to be kept within an optimal temperature range. Regardless of the temperature outside, servers will continue to produce heat and require continuous cooling in order to keep operating. In many data centers, the amount of energy required to keep the servers cool enough to work properly, is equal to the amount of energy these servers require to run.

There are two ways to approach this particular area of inefficiency: improve the servers or improve the HVAC. Both can involve considerable initial costs in order to purchase newer, greener equipment. New servers will generally be built to a higher energy efficiency standard, using less energy and producing less heat. New HVAC equipment also tends to be built to a higher energy efficiency standard, providing more effective cooling while using less energy.

Alternatively, simple changes or retrofits to the HVAC system provides the most cost effective solution to make a data center more energy efficient. According to one expert, relatively simple modifications can save up to 40% of cooling costs. Improving server room airflow, installing more intelligent control systems or using variable speed fans can all bring significant energy efficiency gains.

Additional cost saving measures are available with more advanced retrofits, such as Smartcool's ECO3 or ESM, which can further optimize existing equipment. In 2009, an installation of the ESM at a Dell data center in Bangalore, India, resulted in annual energy savings of 230,400 kWh and will give Dell a return on its investment in just 21 months. The project also brings a reduction in associated GHG emissions of 140,965 kg.

With a vast amount of information available on data center energy efficiency and a large number of cost-effective solutions on the market, it looks like the move to greener data centers is inevitable. And if not… well, we may just have to switch over to hamster/elf power after all since the current energy consumption our IT systems is simply unsustainable.

This is the third in a series of posts on the benefits of retrofitting systems in a variety of different building types.