New research from IHS found that the market for three-phase 400 VAC rack PDUs for data centers grew 150% between 2013 and 2015. IHS estimates that in 2013, three-phase 400 VAC rack PDUs accounted for 2% of units shipped in the Americas. According to new research, that jumped to 6.3% of units shipped in 2015.

Power distribution voltage is a topic that is often discussed in North America. Europe, Africa, most of Asia, and some of South America distribute power in a data center at 415/240 VAC or 400/230 VAC (for simplicity, IHS refers to this range collectively as 400 VAC distribution). In North America, Central America, some regions of South America, Saudi Arabia and Japan, voltage is most commonly distributed at 208/120 VAC, where it must go through an additional step-down transformation before being distributed to the racks.

The North American data center industry has explored a number of alternative voltages including AC as well as DC options. Currently, the most prominent alternative to 208/120 VAC distribution in North American data centers is the 400 VAC distribution scheme used in most of the rest of the world. In this case, increased efficiencies and reduced electrical drops are achieved by bringing 415 VAC directly to the rack and feeding equipment with a single-phase leg of 240 VAC, which requires three-phase 400 VAC rack PDUs, as opposed to the three-phase 208 VAC traditionally used in North America. By tracking the input phases of rack PDUs sold each year, IHS can track the trend of using this higher voltage architecture in North America. Though it is still a small market, the data collected indicates that the market for 400 VAC rack PDUs is progressing rapidly.

Growth in the 400 VAC products is driven almost exclusively by new data center builds because it is not cost effective to retrofit an existing data center with an entirely new power architecture. New data centers using 400 VAC architectures benefit from a smaller step-down transformer, smaller conductors, space savings, smaller cables, and overall increases in energy efficiency.

While other distribution voltage options such as 480/277 VAC and 380 VDC could potentially achieve even greater efficiencies, it seems that 400 VAC is a desirable balance between being a more efficient solution and not being too radically different from traditional architectures. IHS predicts the market for 400 VAC rack PDUs to almost double over its 2015 size by 2020.