Data CenterPower and Cooling

Energy Star Means Real Savings Over the Life of a UPS

It’s been a few months now that uninterruptible power supplies have been eligible to earn Energy Star qualification, and we should know because Schneider Electric was the first manufacturer to receive this designation, with members of the Back-UPS and Smart-UPS families being qualified shortly after UPSs were added to the program. Over the next few months, numerous other systems within our single-phase and 3-phase UPS families became qualified.

Now another member of our 3-phase Symmetra PX family has joined the Energy Star ranks. With the introduction of the second generation of power modules, the scalable and modular Symmetra PX 100kW line of UPS systems will sit in the Energy Star ranks with its larger family member, the Symmetra PX 250kW and 500kW.

Given all this activity, I thought I’d explain a bit about just what Energy Star qualification means, and the kind of savings it can bring from a data center operations perspective.

Launched in 1992, Energy Star is a U.S. Environmental Protection Agency program that helps businesses and individual consumers save money while protecting the environment. The idea behind the program is twofold: reduce greenhouse gas and other pollutants caused by the inefficient use of energy while making it easy for consumers to identify energy efficient products.

Energy Star is a voluntary program under which manufacturers test their products for energy efficiency according to predefined procedures and criteria. If the product passes, it earns the Energy Star label.

A few stats from the Energy Star web site give a sense for the extent of the program:

  • Americans purchased about 300 million Energy Star certified products in 2012 across more than 65 product categories for a cumulative total of more than 4.5 billion products since 1993.
  • Today, 85% of the American public recognizes the Energy Star label
  • Over the past 20 years, Americans, with help from Energy Star, have saved nearly $230 billion on utility bills and prevented greenhouse gas emissions equal to those from more than 350 million vehicles.

For a UPS to be Energy Star qualified it must be in the top 25% of the market in terms of operational efficiency. To determine whether it meets that criteria the UPS has to be tested according to EPA’s test procedures, under the supervision of an independent certification body – which in Schneider Electric’s case is UL. The tests include efficiency ratings at loads of 25%, 50%, 75% and 100% and the results are published on the EPA’s web site.

Testing under a range of loads is important because it’s relatively easy to deliver high efficiency with a full load, but much more difficult at light loads. A UPS that’s, say, 5 years old or more can achieve an efficiency rating of probably no more than 91% when it is 85% loaded or more. If you back off to 30% to 50% load, which is a typical level for many UPS systems, the efficiency drops to probably below 80%.

Our new Symmetra PX 100 UPSs, by contrast, are approximately 95% efficient across a wide range of loads, from 35% on up. Think about the difference between 95% efficiency and 80% and you would expect the savings in electricity to be significant.

And they are. For every 1% gain in efficiency you get in a 100kW UPS, you can expect about $1000 in electricity savings per year, assuming you’re paying 12 cents per kilowatt hour (a typical rate in the Northeast).

But that’s not all. Better UPS efficiency also means you’ll spend less on cooling. For example, the next-generation Symmetra PX 100kW (a 95% efficient UPS) produces 37% less heat than the previous generation (a 92% efficient UPS).  What’s more, choosing an Energy Star UPS may make it easier for you to qualify for rebates and incentives offered by your local utility.

It’s great that customers now have multiple Energy Star qualified UPSs to choose from, but customers would do well to pay attention to the fine print. You’ll notice that Schneider Electric has some of the most energy efficient UPSs in full protection mode, meaning we don’t need to resort to other operational modes, such as eco-mode, to achieve high levels of efficiency. As with cooling systems, when a UPS is in eco-mode, it uses far less electricity. But it also bypasses most of the electronics and circuitry that normally conditions the power that passes through the UPS, possibly putting your data center at risk under certain types of electrical problems.

While some Schneider Electric UPS models have an eco-mode feature that allows for ultra high efficiency, you may not need to resort to that as we still offer efficiency of 95% or better when in full protection mode. You may get an additional 2% or 3% savings by using eco-mode, but it’s likely not worth the risk.

Learn more about our Energy Star compliant Symmetra PX UPSs here – and start saving.


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