The efficiency challenge: Balancing total cost of ownership with real estate demands

With the digital expansion over the past few decades, new requirements for data centers to store, transmit, and manage data of all sorts are reaching a critical level. Companies are feeling the crunch as data centers are filling up quickly with IT equipment, real estate remains at a premium, and power demands and energy prices are skyrocketing. Two primary issues are confronting data centers today. First is the total cost of ownership — which consists of the IT equipment as well as the data center infrastructure used to support operations. The infrastructure includes the power distribution, cooling, cabling, and several other components. Second is the fact that data center real estate is at a premium. Each inch of space within a rack enclosure needs to perform at maximum efficiency vis-à-vis computing performance, power, and cooling. In this article, we will discuss the path to improving efficiency as it applies to AC-DC power supplies (AC-DC front ends) within server equipment. Although the front end is only a portion of the data center power train, the AC-DC front end power supply remains a key element in the efficiency challenge. As a note to the reader, there is a significant amount of activity centered on alternative architectures (in an effort to reduce power train losses and improve overall efficiency) such as 380 VDC or 48 DC architectures. One should be aware that there are always tradeoffs to any approach. In the case of a high-voltage bus such as the 380 VDC, there is a lack of building and maintenance code standards nor connectors or circuit breakers in place today for such a system. For the purpose of this article, we will discuss the existing AC to 12 volt architecture at the server level and what can be done from a power-supply perspective to improve its efficiency performance