Lifecycle costs of data centres are dominated by energy expenses and there is growing backlash over the electricity consumption of centres worldwide

One solution, vaunted by the likes of EcoDataCenter and DigitalRealty is to change energy sources to renewables. Other startups like Cloud&Heat are using hot water cooling technology to recycle waste heat into energy.

Researchers at Princeton and MIT have turned to hardware design to address the issue, discovering a way to redesign power converters that shrinks their size and increases energy efficiency.

Power converters are essential hardware components to any computer, and work by changing the flow of electricity according to the needs of computer’s constituent components. Electricity’s journey through a data centre involves multiple pitstops through these converters.

The research was published this year and last year in IEEE Transactions on Power Electronics, a leading monthly journal focusing on technologies used to power electronics.

The new approach by lead researcher Minjie Chen combines single stage and multi-stage converters to make a new type of “merged multi-power stage” converter.

The new type matches the performance of multi-stage with the lower costs of single stage converters and reduces waste energy. As it is modular in design, engineers can also tack on smaller converters.

“Improving their efficiency and reducing their size means the data centres can be smaller and more powerful while using less electricity for the same demand,” said Chen.

The design method is a significant departure from traditional methods, so we shouldn’t expect modular power converters to progress from lab to industry anytime soon.

Nevertheless, it is no exaggeration to say the potential energy waste reduction for data centres is huge.

In a blog post, Princeton said data centres would be able to fit three times the number of servers in a given space, decreasing energy wastage by 25 percent compared to leading commercial equipment.

A sophisticated modular design at the converter level also opens up interesting technical opportunities for dedicated software programming for individual units.

Other researchers on the paper include Khurram Afridi, University of Colorado, Boulder (now at Cornell University); Sombuddha Chakraborty, Texas Instruments; and David Perreault, Massachusetts Institute of Technology.

The two papers won the first and second place prize paper awards from the IEEE Power Electronics Society in 2017 and 2018, respectively.