415V – Fewer Parts and Pieces
Posted by Isaiah LaJoie on November 23, 2020
- Power Distribution and Monitoring
This article provides a recap of the new Server Technology whitepaper, “Power Efficiency Gains by Deploying 415 VAC: Power Distribution in North American Data Centers.” No time to read the entire document? Not to worry – here, we will summarize how and why 415V and the rack mount PDUs that support higher voltage can save you money. Real money.
Within enterprise data centers, power used for operating, lighting, running IT loads, and cooling is the largest component of operational expense (OPEX) of the facility. Numerous papers and articles have been published by The Green Grid, The Uptime Institute, PG&E, Lawrence Berkeley National Laboratories (LBNL), and others discussing ways to measure, monitor, and increase efficiencies. The Servertech white paper — affectionately dubbed ‘STI-100-008’ — discusses various approaches to reducing power consumption and increasing end-to-end efficiency in the data center by bringing 415 VAC power to the IT cabinet/rack level.
With power densities continuing to rise, more efficient solutions continue to be explored — especially as power cost increases and power availability decreases. The power path from the building entrance to the IT load contains several transformations and conversions, and with each, there is a loss of power. By operating at a higher voltage, you can improve efficiency and reduce electrical costs by avoiding unnecessary step-downs. Seems reasonable, right?
Eliminating transformations and increasing efficiency provides ongoing operating-cost savings, and in turn, reduces the number of electrical devices in your design. Fewer parts and pieces equate to increased savings both today and tomorrow. For me, the white paper can be summarized by the following diagram:
In a 415 VAC distribution system, the line-to-neutral voltage is 240 VAC. It is important to note that this is a significant difference from the typical US Baseline System, where the line-to-neutral voltage is 120 VAC after the PDU transformer. This approach doubles the voltage being delivered to the devices — while increasing efficiencies and reducing installation costs — by eliminating components and using smaller diameter cables for distribution.
The 415 VAC power distribution system that is used in much of the world outside of North America is now beginning to gain a foothold within the United States and Canada. According to various UPS manufacturers, eliminating the PDU transformer will result in a 2% efficiency gain.
Like to know a little more? To read “Power Efficiency Gains by Deploying 415 VAC: Power Distribution in North American Data Centers” in its entirety, click here to access the full white paper.