Data Center Power-Backup Risks

David Wightman is the director of sales and marketing at UST. In the company’s recent webinar, Wightman discussed the risks inherent in current data center power backup. In this article, Wightman discusses a few key points in more detail.

Is reliable, clean power really an issue in the United States?

The United States has one of the best electrical grids in the world. That being said, the U.S. electrical grid is aging and becomes more vulnerable each year. In 2013, the American Society of Civil Engineers (ASCE) gave the U.S. grid a D+ rating. Despite assurances from utilities, many manufacturers who invest millions of dollars in equipment seek options for mitigating the potential damage and downtime caused by transient electrical events.

In the Webinar, you talk about the inherent risks of overtaxing a UPS system. Can you explain?

UPS systems are designed to provide temporary backup power. But because data center facility managers and owners are under extreme pressure to maintain 100% uptime, they also call upon their UPS systems to regulate out of tolerance voltage by continuously monitoring and conditioning power. The assumption is that by having the UPS kick in whenever the incoming voltage goes out of spec, they are reducing the risk of damage due to transient electrical events – sags, surges and swells. But there is a significant downside. Every time the UPS is triggered, its batteries are taxed. Wear and tear is inevitable, as is, we believe, predictable system failure. Using published industry data, we calculate that the cost of unplanned outages due to UPS battery failure alone at an average data center may exceed a half million dollars over the system’s 10-year lifespan.

How does an EVR extend UPS battery life?

Industry research shows that 15% of unplanned data center outages are due to UPS failure. The primary reason a UPS fails is its battery system. In the webinar, we talk about the fact that the typical UPS system is called upon 40 to 60 times a year to make a voltage correction. But in fact, fewer than five of those events are in response to total power loss or deep voltage sag. That means data centers are unnecessarily taxing their UPS batteries 35 to 55 times a year. An electronic voltage regulator could manage those more modest electrical events quite safely and effectively. We believe that including an EVR in data center power-backup system design will cut UPS battery failure rates in half, and perhaps by as much as 90%.

What about UPSs with eco-mode options?

One of the major secondary benefits of including an EVR in power-backup system design is a great increase in electrical efficiency. Data centers use a tremendous amount of electricity. Some estimates show that more than 2% of the world’s electrical output is consumed by data centers. To increase the electrical efficiency of data canters, major UPS manufacturers, including Eaton, General Electric and APC, have introduced proprietary ‘eco-modes’ on their UPS models. But to work as advertised, eco-mode-enabled UPS systems need to be fine-tuned per installation to set the appropriate thresholds. This fine-tuning is expensive and tricky. If sensitivity triggers are set too high, the system will switch too frequently, causing significant wear and tear; if set too low, damaging surges and sags can cause damage to the load,before the system reacts. EVRs are simple by design with no moving parts, and consequently much more trustworthy.

How complicated is it to add an EVR to an existing power-backup system?

For new or existing systems, EVRs are not complicated to install at all. We’ve worked very hard to make our products plug and play. There’s no start-up procedure. There’s no boot-up procedure. It’s a matter of wiring source voltage to the input breaker. As soon as you energize the unit, it begins regulating power. It’s online 24/7 and is fully electronic, so it makes corrections quickly. And there are no moving parts, so there is no maintenance other than an annual inspection and cleaning.

We maintain that EVRs will alter the formula used to determine backup system and facility redundancy for data centers, and have the potential to alter the economics of the industry. Our white paper, “The Weakness at the Heart of
 Data Center Power-Backup Systems. And the Fix.” goes into a detailed financial analysis on this topic.

UST has posted a free recording of the webinar at /ups-webinar.

For more information about data center power backup, contact David Wightman at (518) 326-4142.