Data centers have been around for a long time, but only lately have they started to appear on the radars of small- to medium-sized companies.

This is due in large part to the increased reliance on computing for companies that are now seeing big opportunities from internet-facing sales, and also to the simultaneous awareness of the high costs of and limited power available to rapidly expanding data centers or server rooms.

David Chernicoff, the author of a new book from Realtime Publishers, "The Shortcut Guide to Data Center Energy Efficiency," has been working on data centers since the late 1980s, and he sees now as an opportune time for data centers to upgrade and get greener at the same time.

Because the majority of data centers are aging, between 10 and 20 years old, and are getting close to the end of their useful lives -- Gartner estimates that as many as 80 percent of data centers are in need of overhauling -- Chernicoff says he's getting more calls than ever about energy efficiency in data centers.

"People will pick up the phone and ask me, 'What does it mean to be a green data center?'" Chernicoff explained in a recent phone interview. As his customers, which consist largely of SMEs, look at how much technology has changed since their data centers were originally built, they want to know all about "green IT."

The problem? "Everyone says they want to be green," Chernicoff said, "but no one wants to spend any money on it."

It's the oldest story in the book, of course, and one that is especially true with green projects in general. But Chernicoff says that the benefit of green technologies like virtualization is that it makes many IT revamp projects possible with ROI times so short as to seem almost immediate.

"I usually step people back from the green part of it," he explained. "I'll walk through what happens when you virtualize: If you go from 10 servers to one, there you go -- you're greener."

Chernicoff added that people are finally starting to realize that there are too many servers out there doing too little, and that for a lot of simple projects, virtualization makes a lot of sense.

But even for bigger projects, virtualization makes it easier to cram more computing power into a smaller space than ever before. Chernicoff summed up a typical project in a thumbnail sketch:

"I can concatenate this entire data center into a dual-rack row, wrap it up as a hot aisle, and I can deliver five times the power of what I did five years ago."

Of course, the reality is quite a bit more complicated than that, and that's where Chernicoff's book comes in. It is aimed at those companies that have older data centers, ones that were built in the days when computing capacity and availability was the only relevant statistic, before the rise of PUEs and DCiEs.

These firms are looking to expand and improve their computing capacity, rather than building entirely new facilities, and they know they can do things to improve efficiency and performance, but don't know where to begin.

Chernicoff's book provides a details walkthrough of every aspect of data center operations, beginning with a section on virtualization, and progressing through data center design, critical issues for heating and cooling servers, and strategies for upgrading currently operating data centers.

As he writes in the section on "The Costs of Not Upgrading" a data center:

As power costs continue to increase, there will be a hidden tax on inefficient data centers. This wasted money is difficult, in many cases, to quantify, but it is a problem nonetheless. With tight IT budgets the norm, wasting money because of a lack of progressive thinking in your data center is a waste that can be difficult to sustain. Beyond the simple cost issues, there are potential problems that can arise from failing to update your data center.

The most significant is the inability to deliver the services and technologies that the business will demand in the near future to remain competitive or to create a competitive advantage. With the changes in IT technology resulting in much more dense data center IT loads, it is critical that IT be able to support those loads and have an agile and adaptable data center infrastructure. The inability to deliver the necessary power and cooling services in the data center will prevent the business from taking advantage of the technological edge that efficient IT can deliver.

Regardless of any legislation impacting data center owners or energy providers, the steadily rising costs of energy -- as well as predicted increases in power shortages -- mean that a shift to more efficient IT now will save headaches later.

"It boils down to if you don't spend the money now, you're going to spend it in the future."

David Chernicoff's book, "The Shortcut Guide to Data Center Energy Efficiency," is available as a free download from RealTime Publishers.

_{Photo CC-licensed by Flickr user cbowns.}