If you were in the position to start from scratch with power distribution, what would you do? For many of our education customers looking at planning a new facility, the answer is to completely rethink the norms. Many data center managers are making do with the power distribution that came with the building, and for most, the system is not current. No pun intended.
Given a new-build situation in which all ideas are on the table, more and more users are looking for better efficiencies and going to higher voltages to support their IT loads. “We were fortunate to be able to explore all of the options that are out there,” states Dave Fahey, North America Sales Director for Server Technology about a recent campus project. “The first thought when we sat down with the engineering team was to go with what they knew. Fortunately, they approached the project with an open mind and looked different distribution voltages.”
Here are a few things to help keep your mind open as you head down this road:
Avoid transformation. The most typical scenario is to begin with a 480/277 service, commonly delivered to large commercial buildings in the US. Instead of dialing the service down to 208/120V, either at the UPS or PDU level by way of a step-down transformer, users are specifying an autotransformer in their UPS or PDU that delivers 415/240V to the rack level, and 240 to the appliance. This method not only saves on equipment cost but also generates a 2% energy savings that would be assigned to the transformer loss.
Mind the gap. By going to 415/240V, users understand that they will be delivering much higher voltages to the rack, which must be accommodated in the design. It is important for staff to be educated on working near higher voltages, and to update company change management processes to reflect this accommodation. Additionally, temperature monitoring and PDU-level controls will be essential. And don’t forget the plug – electronic equipment operating at 240V will need IEC-based cords!
Efficiency up, cost down. The procedural changes are worth their weight in increased efficiencies and energy savings. On top of the 2% gain realized by eliminating the transformer, most server and storage equipment operates more efficiently at 240V than either 208V or 120V. Add in savings from avoiding line losses, and users can expect savings in the 4 to 5% range. According to a Server Technology white paper on the topic, even at a modest 750 kW load, this energy savings translates to $32,850 per year assuming a $.10 kW/h rate. Over the lifespan of the facility, say 10 years, this equates to $328,500 in savings at the given load. And the higher the load, the higher the efficiency, and the higher the total savings.
While there may be a learning curve involved with working with new voltages, the reward from higher efficiency is certain. “It is mostly a matter of rethinking what you know,” comments Fahey. “Our customer was able to learn about a different side of the power world, and I’m glad they did because the cost savings helped fund the program.”
To see if rethinking your current strategy is right for you, take a look at our white paper on power efficiency gains, or ask us a question in the form on the right.