Trends in data center power was the topic at AFCOM New England Chapter’s meeting this week, and apparently it’s a subject that resonates with members—at least judging by the nearly 100 attendees who showed up. (As the New England chapter enters its third year, President Rocko Graziano, whose real job is manager of infrastructure operations and services at L.L. Bean, said this was the largest meeting yet). Two speakers gave the audience their take on the some emerging trends they see taking shape.

Rudy Kraus, CEO of Validus DC Systems, a provider of direct current (DC) power infrastructure for data centers and telecommunications facilities, naturally sees a bright future for data centers powered by DC rather than AC-based electricity. Kraus cited a number of statistics from the likes of the Uptime Institute and McKinsey outlining just how much power data centers can save by switching to more efficient DC power. If data centers in the United States converted only 10% of their capacity to DC power, that would eliminate $1 billion in electric bills. The co2 emissions for a 10 megawatt data center with 17,500 servers would drop from 99,776,400 pounds to 59,865,840 pounds. Kraus invited members of the audience to do their own comparison by visiting an online calculator offered by Intel that analyzes facility-level efficiency of AC and DC servers.

The other speaker, Brian Ouellette, of J.S. Fleming Associates, a provider of power and cooling systems, spoke about the five power trends heading to a data center near you. The top trend, that energy efficiency is gaining importance, is pretty self-evident. The other four trends centered on ways to make data centers more efficient: New ways to scale UPS architectures into adaptive models that can adjust to changing power requirements; two-stage power distribution that reduces restrictions to cooling air flow, among other benefits; increasing use of monitoring with tools such as smart power strips (that monitor in-rack power) and branch circuit monitoring (that monitor each PDU output circuit). Ouellette also pointed out that data centers don’t have to go high-tech in order to become more efficient. When Ouellette asked the audience whether they use blanking panels in their data centers, only five people raised their hands. “Blanking panels are a great way to get the air where you need it,” he said. “Otherwise, you’ll get cross-contamination of air from your hot aisle and cold aisle.”

Alan Warn, a data center manager at ABN AMRO who I spoke to last week for a story on CFD modeling in the data center, also had some things to say about Cisco switches and EMC storage devices.

Neither are new issues for data center facility managers, but they bear repeating. A popular Cisco LAN switch, the Catalyst 6500, blows its hot air out the sides, wreaking havoc on facility managers who are trying to arrange a hot-aisle, cold-aisle configuration in their data center.

“Cisco switches are getting harder and harder to cool,” Warn said. “Their processing equipment, the cooling runs side-to-side. It’s just madness.”

Last year, we asked Doug Gourlay, Cisco’s senior director of data center solutions, about that exact issue in a Q&A we had with him. His answer? The Catalyst 6500 is actually offered in a front-to-back airflow configuration as well, but many data centers don’t buy it because you can’t fit as many ports into it as in the side-to-side version. The bottom line is that if you buy Cisco switches, you have sacrifice either proper airflow or port density, neither of which is very attractive.

Warn said he is looking at some APC cabinets that have special fans to take air from the sides and force it out the back.

Terry Rodgers, an associate partner at data center consultancy Syska Hennessy, recently wrote to us regarding our story on computational fluid dynamics (CFD) modeling. He said that CFD modeling is too expensive to be used by data center managers simply to tell them that they should be following best practices on reducing bypass airflow.

“Why pay tens of thousands of dollars to find out that yes, you should follow accepted best practices?” he wrote. “CFD is not necessary to identify and seal cable cutouts, holes in the data center perimeter, use blanking panels in racks, and remove perf tiles from the hot aisle.”

He added that CFD isn’t even necessary to finding hot spots in the data center. “Just walk around and check and take a temperature sensor with you.”

The better strategy, he argued, is to correct all of those airflow issues that you can, and then use CFD modeling to help you rearrange server cabinets, for example, or determine whether your air conditioning units are providing the airflow pressure that they should.

“Another use for CFD is to validate design strategies before proceeding with costly construction,” he wrote. “But to tell me to seal cable cutouts???”

We agree. A CFD analysis can cost a pretty penny and should be used primarily to pick up the more nuanced cooling issues in your data center, the ones not easily seen with the naked eye. When half of your floor tile is gone to get some cables through it, it doesn’t take a rocket scientist analyzing complex algorithms to determine that you’ve got to fill them up. Thanks to Rodgers for writing in.

Does this look familiar? A SearchDataCenter.com reader (who shall remain anonymous) sent these pictures in from his facility and let me post them here. You can click on the images to get the full-size version. His data center is currently in the midst of some CRAC maintenance, and this duct work is the result. Anyone else out there have similar experiences going on (past or present)?

Chuck Goolsbee, blogger and data center manager, is multi-talented: The guy can put together a slick video too — check out the installation of a new rooftop HVAC unit at Seattle-based hosting company Digital Forest in this video. Make sure you’ve got the volume cranked. The music rocks.  

In this podcast, Uptime Institute and ComputerSite Engineering Inc. guru Pitt Turner explains the difference between sensible and latent cooling in the data center. Latent cooling in the data center results in wasted energy. Turner outlines how to avoid spending more energy and money to cool servers than is necessary in this podcast from the Uptime Institute Data Center Design Charrette.

SANTA FE, N.M. — The American Society of Heating Refrigerating and Air-Conditioning Engineers (ASHRAE) is considering expanding its recommended specifications for server temperature and humidity ranges. Last week at the Uptime Institute Data Center Design Charrette, I spoke with Roger Schmidt, distinguished technologist at IBM and chairman of ASHRAE Technical Committee 9.9, about the plans in this podcast.

There are two reasons to increase the operational temperature range for servers:

The barriers to widening the ranges are the potential for hardware failure and the cultural issues and career risk to pushing these boundaries. But Charrette attendees generally agreed that the servers can withstand higher temps and humidity levels. The current ASHRAE recommendations specify server temperatures between 20 degrees to 25 degrees Celsius and relative humidity between 40% to 55%. Attendees recommended that ASHRAE modify its range to 18 degrees to 27 degrees Celsius and a humidity range of 30% to 55%. It should be noted that the “recommended” ranges are narrower than the “allowable” ranges for IT equipment.

SANTA FE, N.M. — Last week at the Uptime Institute Data Center Design Charrette, I spoke with Roger Schmidt, distinguished technologist at IBM and chairman of ASHRAE Technical Committe 9.9 about ASHRAE’s role in standardizing a process for data center managers to measure their physical infrastructure energy use. A lot of data center managers want to reduce energy consumption but don’t have the tools or processes to measure their usage. In this podcast, Schmidt outlines ASHRAE’s role in dealing with this problem.

Fujitsu has a fuel cell from UTC Power up and running at its Sunnyvale, Calif. campus. The 200-kilowatt fuel cell is helping to run the company’s chiller plant, which in turn is cooling the data center.

Though Fujitsu is talking about how it is the first high-tech company in California to put the fuel cells to use, there are other companies who have been using them. Verizon in New York and the First National Bank of Omaha are no strangers to the technology. Fujitsu said it’s considering buying more fuel cells to directly power the data center, and is working with UTC Power to get one that can operate at variable loads instead of the steady 200 kilowatts all the time.

So what is fuel cell technology? Basically, the fuel cell module takes natural gas and strips the hydrogen from it. The hydrogen then runs through a fuel stack, and when it is combined with oxygen, it generates electricity. The byproduct is mostly water vapor with a little carbon dioxide mixed in.

Meanwhile, UTC Power’s fuel cell module, the PureCell, takes up 180 square feet and creates 925,000 BTUs of heat per hour. At Fujitsu, that heat will go into water to be piped back into the boiler system and used in the office environment for heat.

Fujitsu wouldn’t say how much one of these modules costs, but it must be big bucks because they’re getting a ton of rebates on it. Pacific Gas & Electric is giving them $2,500 per kilowatt and the federal Department of Energy is giving them a tax credit of $1,000 per kilowatt. For a 200 kilowatt module, that adds up to $350,000 in rebates and tax credits. Not too shabby.

Still, there is the persisting fear out there, sarcastic or not, that hydrogen power is not safe. What do you think? Would you ever consider using fuel cells to power your data center? If you need fuel to ponder it, check out our two-part series on hydrogen fuel cells in the data center.

We write a lot about optimizing data center cooling — engineering advice from thermodynamics masterminds with perfect data centers. But what about the worst data center cooling you’ve ever seen? We asked readers to send us their duct-taped data center cooling horror stories. This week we’re publishing responses in the data center blog.

The neighbors froze our data center

Our office is underneath a laboratory where they manufacture cryogenic equipment housing liquid nitrogen. On May 24, 2006, one of the pipes in the lab above us burst and there was so much condensation in our storage facility that it took the disaster recovery unit three days to scrape off chunks of xenon tetrachloride residue from our rack mounted servers. Our downtime was over two weeks and we lost 13 terabytes of backup data. Fortunately our original data was able to be used to backup the backups. Our attorneys are still involved in the insurance claim!

Since then, we have switched to HP blade servers and virtualized storage at a remote location. I don’t know a horror story worse than ours, but I am anxious to read some of the others.

S.F.

CRAC Band-Aid: It’s ugly but it works

Our data center had become so crammed with servers that the two CRAC’s were unable to maintain temperature. When one went down we had to open all of the doors to try and keep the servers from overheating. The data center was also expanded without regard for cooling and power (another nightmare issue with only two PDU’s). The new size really needed an additional unit or two but none was purchased. The attached photos are the Plant Engineering department’s solution to our cooling problems. Ugly as it is the solution worked, however we are embarrassed to show the space to anyone.

We just completed construction of a brand new data center building so we are abandoning this space for that purpose, thankfully. The new space has six CRAC’s with redundant power sources and chillers each capable of maintaining temperature for the space. In addition the power problems have been solved with six PDU’s with lots of room for growth.

M.R.

Mini-data center meltdown

The worst cooling I ever had to deal with was in a tiny little company that moved all three of its servers, plus communications equipment, to the last empty office upstairs — with no vents and no cooling. All I had was a single desk fan to keep the air moving around in the hope that some of it would escape under the door. I couldn’t even open the window — it faced south, and the merest zephyr of a breeze would blow the vertical blinds all over the place, allowing the sun to fall directly on the sides of the servers. They were IBM servers, too — very black, very capable of absorbing radiated heat.

Then I discovered that the ceiling tiles could be removed and the heat could all just vent into the roof space.

M.M.

This old data center

A few years back we were moving to a “new” office building. We rented the whole floor in a turn of the century (20th, not 21st) building. The whole floor was gutted, right down to bare cement floors, walls and ceiling and refitted with modern materials. That included new HVAC throughout. On the blueprints two rooms were designated specifically for computers. Our computing needs weren’t all that big, but we did have a huge legacy (ie 1960’s, 4ft wide, 2ft deep, 6ft high) power conditioner.

The first sign of problems was the minor issue of 20 missing workspaces (turns out the floor plan wasn’t square and planners worked from the largest measurements). The next problem was the “computer room”. Within a day of moving in, the room temperature was up around 100 deg F. The locked door had to be left propped open and an old painted over window had to be forced open.

The computer room solution was to retrofit an exhaust fan from directly outside of the building. Even with the “new” retrofitted HVAC system the whole floor had heating and cooling problems year round. In the winter just walking down the corridor between the cubicles you could walk through a 20F degree range in 10 feet, from 65F down to 45F. Yes, some of us had to wear jackets and gloves sitting at out desks!

The final solution was that we moved to a newer building at the end of the 5 year lease.

R.S.

Names have been abbreviated to protect the innocent! If you have a great cooling story, leave feedback in the comments section.