As belts tighten and budgets shrink, CIOs and IT directors are scouring every last line item for inexpensive fixes and major savings. The data center’s electricity bill has emerged as a major target of opportunity. You don’t need to rip out and replace your equipment to drive efficiencies in power and cooling. Often, the savings are right under your nose.

“The impact of the economic downturn is really twofold,” says Tim Hirschenhofer, director of sales for Degree Controls’ AdaptivCool division (www.adaptivcool.com). “Customers want to save money, and certainly controlling airflow and HVAC costs are the easiest ways to gain efficiencies in the data center. This approach also extends the life of existing data centers by allowing more equipment to be put into the same size facility.”

Here are a few suggestions to get you started on scaling back your HVAC power consumption.

Get An Energy Audit

An audit identifies where your HVAC infrastructure works and where it doesn’t. Beyond helping find hot spots and potential trouble areas, it also lays the groundwork for data center managers to educate themselves about power management best practices. Most vendors these days provide basic audits at no cost.

Manage Your Airflow & Eliminate Obstructions

“The immediate knee-jerk reaction to a thermal problem is to add more cooling equipment,” says Hirschenhofer. “But the reality is that most data centers today have more than enough cooling to handle the heat load that they’ve got.”

Airflow distribution is critical to getting the cold air where it’s needed and in the right amount, he says. By actively managing airflow—possibly through airflow management units under a raised floor or in a dropped ceiling—you eliminate hot spots.

“You’re not adding more cooling. Rather, you’re using what you’ve got more effectively,” Hirschenhofer says. “This allows you to run your cooling equipment much more efficiently so you don’t have to cool to the warmest spot in the room anymore.”

Additionally, anything that blocks the free flow of air above or below a raised floor raises the potential for hot spots.

“Servers should ideally be pulling cold air from the front and exhausting warm air out the back,” says Rob Kubik, power and cooling specialist at CDW. “A badly placed power strip, UPS, or cable can get in the way. Sometimes, even a simple adjustment can allow the air to go in and out as quickly as possible.”

Maintain Your Equipment & Its Placement

Equipment placement within a rack is crucial to effective cooling, airflow, and energy conservation. In a partially empty rack, move the installed devices as close to the floor as possible to take advantage of the cooler air below. Bottom-to-top placement also gives you more redundancy in the event of an outage.

“Being at the top of the rack is not the place to be if there’s a cooling failure,” says Steve Spencer, president and CTO of Digital Fortress (www.digitalfortress.ca). “You’ll be the first one to fry.”

Spencer adds that drive arrays should be moved toward the floor, as they’re heavier and tend to run hotter. Adjusting vertical placement reduces hot spots and improves cooling efficiency.

UPSes can also be major sources of wasted energy. Kubik says a UPS with a low power load is significantly less efficient than one running closer to its load capacity. He recommends consolidating them to raise efficiency. As an added bonus, consolidation simplifies management.

Accelerate Virtualization

Today’s multicore processor-based servers run more processes and applications more efficiently, delivering greater capacity without commensurate increases in heat loads or energy consumption.

“Virtualization makes more processor cycles available for less heat load,” says Spencer. “It also scales extremely well, allowing you to, for example, go from 1,000 to 2,000 concurrent users on the same box with little change to the heat load, which positively impacts your power usage.”

Make The Utility Bill Visible

It may be difficult to appreciate excessive energy consumption as long as someone else is paying the bill.

“A lot of folks are being shown that electric bill now, and they’re being held accountable,” says Kubik. “So whether there’s a problem or not, they’ll have to run through the paces to see what they can do to reduce power consumption.”

This level of visibility makes it easier to track energy performance in the data center. “Many shops don’t measure their consumption as diligently as they could be,” says Kubik. “So it’s been a free-for-all—they add a UPS here, a cooling unit there, all to address tactical cooling needs. But they don’t really know what they’re consuming.”

Change Your Thinking

Saving energy in the data center is as much based on attitude adjustment as it is on changes to physical infrastructure. Changes to long-held assumptions about environmental management can go a long way toward driving efficiencies.

“The room doesn’t have to feel like a meat locker to adequately cool the equipment,” says Hirschenhofer. “It’s okay for server intake temperatures to go as high as 77 degrees and still be in the safe zone. That’s a little bit hard for some data managers to accept. They’d much rather walk into the room and be cold immediately.”

Additionally, Kubik says there’s often a disconnect between IT and facilities. “Even though their offices may be across the hall from each other, they’re not necessarily talking,” he says. “We encourage everybody to get onto the same page.”

As an example, airflow management initiatives that move hot air into a drop ceiling may cause ripple effects beyond the data center. If the building uses the plenum space for other systems, hot air from the data center may cause problems there. Stronger partnerships can ensure win-win solutions for both IT and the facilities teams.

by Carmi Levy