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The Importance of Green IT

📄 Contents

  1. The Growing Significance of Green IT and Green Data Centers
  2. All Companies Can Take Basic Steps Toward Green IT
  3. What This Book Covers
John Lamb, author of The Greening of IT, explains the basic environmental impact of IT — including data centers’ consumption of fossil fuel-based electric energy — and lays the foundation for solutions to those problems.
This chapter is from the book

Editor's Note: For more information on Green IT from John Lamb, see also:

“As more and more people understand what’s at stake, they become a part of the solution, and share both in the challenges and opportunities presented by the climate crises.”
Al Gore on global warming

Information Technology (IT) is at the heart of every successful modern business. Without it, success is impossible. Yet, the pervasive deployment of IT has had significant, unintended side effects, namely as a significant contributor to the economically unsustainable worldwide dependence on fossil fuels. The awareness of these side effects, though somewhat late in coming, has led some successful companies to turn to a sustainable practice known as “IT greening.” IT greening is about using IT more efficiently to achieve reductions in energy consumption, and therefore, considering the acquisition of energy-efficient IT solutions. Within this book, you can find details on the environmental impact of IT, including data centers’ consumption of fossil fuel-based electric energy. In addition, we examine many case studies, extracting lessons learned and best practices for implementing green IT.

IT is so pervasive that energy efficiency through the implementation of green IT has moved to center stage for many companies in their pursuit of environmentally helpful practices. This book provides details on the importance of implementing green IT; the significant and growing role of IT and data centers in the world’s consumption of electric energy and carbon footprint; and especially the case studies for “lessons learned” and the best-practice approaches for implementing green IT.

As I mentioned in the Preface, green IT is an ideal way for most companies to make a significant step in reducing their carbon footprint for several reasons. First, for competitive reasons, most companies already refresh their computer hardware—laptops, desktops, servers, and storage devices—every three to four years. That refresh cycle provides a recurring opportunity to buy increasingly energy-efficient technology, such as virtual servers, virtual networks, and virtual data storage. Such virtualization can easily reduce IT power consumption for the replaced equipment by up to 50 percent. (For examples, refer to the Environmental Protection Agency’s [EPA] “Report to Congress on Server and Data Center Energy Efficiency” or the reports by Jonathan Koomey listed in the Bibliography.) A second compelling reason to move to green IT is that virtualization technology enables you to reduce equipment and system management costs for your data center. Data center green technology is based on a solid business case—even before we consider the savings due to reduced energy costs. A third reason for moving to green IT is that all large companies are moving to such implementation improvements (in IT virtualization, cloud computing, and so on). In addition to information on IT virtualization, this book also includes information on new energy-efficient cooling technologies that support IT, and the impact of electric utility-rate case incentives and government incentives and regulations on promoting IT energy efficiency.

Green IT has many different aspects. In this book, we use the terms green IT, green computing, and green data centers. Green IT—as used here—is the most comprehensive because it includes all computing, inside and outside the data center. The emphasis of our discussion is on the business aspects of green IT, so the focus is on what to do, rather than the details of how to do it. However, several chapters, especially the case studies, do give details on how to implement green IT, using best practices based on recent experience and lessons learned through dealing with many companies and organizations throughout the world.

In the following chapters, we look at the benefits and roadblocks in moving to green IT, including the following:

  1. Organizational issues in addressing the problem (for example, CIO doesn’t pay the electricity bill).
  2. The future of regulations as external factors for change.
  3. Overall motivation for executives to move to green IT.
  4. Evaluation of product end of life and asset disposal, procurement policies, and supply-chain issues (solutions to avoid climate impact, and such).

Executives have one significant aspect of motivation to move to green IT that is not covered in any depth in this book, and that is the area of corporate social responsibility. A growing body of evidence shows that companies can do well by doing good. In fact, books have been written about this corporate motivation for going green. (See the reference to Green to Gold in the Bibliography.) The Internet’s ubiquitous connectivity has created new relationships among businesses, customers, employees, and partners. People now have access to massive amounts of information and opinions about products and company practices. This information is available in every part of the globe, every minute of every day. Collaboration over the Internet is taking place during a time of increased visibility of corporate actions, a time when customers’ perceptions of companies—and their consequent purchasing behaviors—are fundamentally changing. Thus, having your company become part of the green wave (to use a term used in the Green to Gold book) should be an additional motivation (besides the standard business case) for companies to pursue green IT.

Although this book emphasizes the business aspects, rather than the technical aspects, of green IT, several chapters give technical details, including the case study chapters (Chapters 9, 10, and 11). I’m an engineer by training, and I’m fascinated by the technical aspects of green IT. The energy used for green IT and green data centers is electricity, so I would like to give a brief review of the familiar electricity concepts and relationship of volts, amps, and watts, which are fundamental in our quest to reduce energy used for green IT. The relationship between volts, amps, and watts is this: watts = volts × amps. A watt is the measure of electrical power. Energy is power over a unit of time. We pay for electricity in terms of energy used with a measure of kilowatt hours or KWH. One kilo watt hour (KWH) of electrical energy is the energy used by having 10 one-hundred-watt light bulbs on for one hour. In the New York City area, one KWH costs about 20 cents, whereas in West Virginia, a KWH costs only about 5 cents. The big difference in cost is due to the big difference in generation costs. With the high cost of electricity, the region of the country is becoming a significant factor in deciding where to locate a new data center.

Besides the cost per KWH, another aspect of basic electricity to consider for your data center is the voltage level. In the United States, we typically have two voltages to use in our homes, offices, and data centers: 110 volts or 220 volts. The actual volts can fluctuate somewhat during the day (as you can discover using a simple voltmeter), and electrical engineers often give the two voltages available as 120V or 208V. If you have an electric range, an electric clothes dryer, or a large electric air conditioner in your home, they’ll be connected to the higher 208V service. The reason is that they need more power; using a higher voltage gives more power and also saves energy. Higher voltage saves energy because the formula for electric losses due to transmission over a wire is I2 R, where I represents amps, and R is the fixed resistance of the wire. Because watts = volts × amps, we can double the power (watts) by doubling the volts or doubling the amps. However, doubling the amps would increase the losses by four times. Thus, to transmit electricity over long distances, the practice is to increase the voltage as much as possible. In high-tension towers, the voltage is often as high as 120,000 volts, and even in the power lines outside our houses, the voltage is often 4,000 volts. That voltage drops to 110V for use in our houses to reduce danger of electrocution. As noted, 220V power is used only for electric ranges, clothes dryers, and so on, although in Europe, the base power is 220V. One easy way to reduce energy transmission losses at data centers is to use 220V (208V) service. Higher input voltage results in more-efficient operation. Most servers (just like our laptops or hair dryers) are capable of either 110V or 220V service. Older data centers often have 110V power sources for servers, but switching to 220V (208V) would provide significant savings. This change in voltage at data centers to reduce energy use is mentioned in several places throughout the book.

The Growing Significance of Green IT and Green Data Centers

Much of the emphasis in the following chapters is on data centers because they almost always represent the starting point for green IT initiatives for companies. Data centers—the facilities that primarily contain electronic equipment used for data processing, data storage, and communications networking—have become common and essential to the functioning of business, communications, academic, and governmental systems. Data centers have been growing and expanding quickly as our economy continues to shift from paper-based to digital information management. The U.S. EPA’s 2007 “Report to Congress on Server and Data Center Energy Efficiency” estimated that the energy use of the nation’s servers and data centers doubled from 2000 to 2006 to approximately 61 billion KWH. Under current efficiency trends, national energy consumption by servers and data centers could nearly double again by 2011 to more than 100 billion KWH, representing a $7.4 billion annual electricity cost.

Data centers are found in nearly every sector of the economy, including financial services, media, high-tech, universities, and government institutions. Dramatic server growth at data centers is indicated by well-known web services such as Google, Amazon, and eBay. Estimates indicate that Google maintains more than 450,000 servers, arranged in racks located in clusters in cities around the world. Google has major data centers in California, Virginia, Georgia, and Ireland, and new facilities in Oregon and Belgium. In 2009, Google is planning to open one of its first sites in the upper Midwest in Council Bluffs, Iowa, close to abundant wind power resources for fulfilling green energy objectives and proximate to fiber optic communications links. For additional information on the positioning of new data centers close to abundant renewable electric power sources, see Appendix C, “Comparison of Different Power-Generation Methods.” Amazon.com and eBay also have thousands of servers. It is estimated that the Second Life Internet-based virtual world launched in 2003 has more than 9,000 servers. Even with these large numbers of current servers, IBM consultants estimates that in the next decade, server shipments will grow by six times and data storage by an amazing 69-fold.

Green energy-efficient data centers can help us reduce greenhouse gases—which, in turn, can help reduce global warming. The recent UN and White House sessions on climate change emphasize the environmental importance of green projects. Although the extent of the global warming danger might continue to be open to debate, implementing green data centers presents a significant opportunity for all of us to help reduce greenhouse gasses.

In many instances—such as building alternative energy sources by implementing solar panels, or wind turbines—going green has not been economical and can be justified only by government or energy utility rebates. Yet implementing green data centers can be quite financially rewarding—especially when you go first after the low-hanging fruit. As I’ve indicated throughout this book, going to green IT is a win/win for all parties involved. Energy expenditures for IT keep increasing. Figures mentioned previously bear repeating. According to the research firm IDC: By 2010, for every $1 spent on hardware, 70 cents will be spent on power and cooling, and by 2012, for every $1 spent on hardware, $1 will be spent on power and cooling. Green IT has generated significant customer interest throughout the world. Much of the interest comes from the financial return on green data center investment.

Here is a general definition of a green data center: A repository for the storage, management, and dissemination of data in which the mechanical, lighting, electrical, and computer systems are designed for maximum energy efficiency and minimum environmental impact. The construction and operation of a green data center involve use of advanced technologies and strategies. The strategies and goals include the following:

  • Minimizing the footprints of the buildings
  • Using low-emission building materials, carpets, and paints
  • Creating sustainable landscaping
  • Initiating waste recycling
  • Installing catalytic converters on backup generators
  • Using alternative energy technologies such as photovoltaics (PVs) and fuel cells
  • Increasing the efficiency of heat pumps, variable speed fans, and free-cooling technology

However, in the following chapters, we concentrate on the ways data centers can become more energy efficient by first exploring the low-hanging fruit. The basic technologies that we should first examine for existing data centers range from the use of efficient cooling towers and variable speed blowers to the use of energy-efficient IT systems, such as virtual servers, blade centers, and virtual data storage. Server consolidation—although initially undertaken to save server hardware capital—is also an excellent way to reduce server energy use. A step way beyond server consolidation is data center consolidation—also done to reduce facility and personnel resource cost; however, a significant side effect is reduced data center energy use. Most data centers have already started to employ newer IT technology such as virtual servers or server consolidation, so this book first explores the technologies that have already started to be employed at your data center for capital cost-saving—and discuss the ways this same technology can significantly reduce energy use. The experiences described in the case studies presented in later chapters are a way to leverage those lessons learned for your data center.

Many consultant reports indicate that data centers are at a “tipping point.” Some well-publicized issues supplying adequate electrical power to data centers include Canary Wharf in London and the area south of 14th Street in New York City. In 2006, the financial institutions at Canary Wharf were told that the power infrastructure could not supply power for additional servers at their data centers. In recent years, financial organizations have been adding significant server power, often with racks of blade servers. The racks of blade servers can greatly increase the power required per square foot in the data center. Each blade server requires about the same energy as larger, older servers, and the data center needs similar levels of electricity to cope with the heat generated. Canary Wharf didn’t have the power infrastructure to support the increased demands. A similar limit of the power structure occurred during 2008 for data centers south of 14th Street in Manhattan. Power restrictions to data centers based on inadequate power infrastructure is only a part of the problem. Data center floor space has also become a significant concern for data centers, especially in large cities. Often, a company runs out of data center floor space with no easy capability to expand.

The green IT techniques described in later chapters (such as server and data storage virtualization, and server consolidation), in addition to cutting power requirements by 50 percent, also reduce data center floor space requirements. Using virtual server techniques to replace ten stand-alone physical servers with one large physical box that includes ten virtual servers can easily reduce the data center floor space required by 80 percent. Practicing green IT promotes a “win-win” situation for all aspects of your data center: electric-power reduction, server cost, data center floor space, and management of the physical boxes.

Although building and certifying a green data center or other facility can often be expensive upfront, substantial long-term cost savings can be realized on operations and maintenance. The green data center technologies described later can all be based on the typical business case, where a significant return on investment (ROI) would be required before proceeding with a project. Of course, there are also significant nonfinancial returns to consider—because green facilities (including green data centers) offer employees a healthy, comfortable work environment. In addition, we cannot ignore the fact that green facilities enhance relations with local communities.

We are all aware of the growing pressure from environmentalists and, increasingly, the general public for governments to offer green incentives: monetary support for the creation and maintenance of ecologically responsible technologies. Server refresh offers data centers a convenient opportunity to go green, which always makes economic (as well as environmental) sense. IBM estimates that a typical 25,000 SF data center with electrical costs at 12 cents per KWH will cost a company $2.5 million a year in electrical energy costs for IT power and cooling. IBM also estimates that the typical data center can reduce its annual electricity cost by up to 50 percent by going green. Of course, as energy costs continue to climb, so will the savings due to the installation of energy-efficient IT equipment and optimization of data center cooling techniques.

Recent EPA reports stress that the U.S. data center industry is in the midst of a major growth period stimulated by increasing demand for data processing and storage. This demand is driven by several factors, including the following:

  • Increase in electronic transactions in financial services, such as online banking and electronic trading
  • Growth of Internet communication and entertainment use
  • Increase in online shopping and related transactions
  • Shift to electronic medical records for healthcare
  • Growth in global commerce and services
  • Adoption of satellite navigation and electronic shipment tracking in transportation

Other important trends contributing to data center growth in the government sector include the following:

  • Use of the Internet to publish government information
  • Government regulations requiring digital records retention
  • Enhanced disaster recovery requirements
  • Emergency, health, and safety services
  • Information security and national security
  • Digital provision of government services (for example, e-filing of taxes and U.S .Postal Service online tracking)
  • High-performance scientific computing

During the past five years, increasing demand for computer resources has led to significant growth in the number of data center servers, along with an estimated doubling in the energy used by these servers and the power and cooling infrastructure that supports them. This increase in energy use has a number of important implications:

  • Increased energy costs for business and government
  • Increased emissions, including greenhouse gases, from electricity generation
  • Increased strain on the existing power grid to meet the increased electricity demand
  • Increased capital costs for expansion of data center capacity and construction of new data centers

For these reasons, there has been mounting interest in opportunities for energy efficiency in this sector. To its credit, the Information Technology (IT) industry is actively investigating and developing solutions, such as power-managed servers and adaptive cooling.

The direct energy use of IT and infrastructure equipment is not, however, the only way that data centers affect energy use. The data-processing and communication services provided by data centers can also lead to indirect reductions in energy use in the broader economy, which can exceed the incremental data center energy expenditures in some cases. For instance, e-commerce and telecommuting reduce both freight and passenger transportation energy use. When we use an electronic bookstore such as Amazon.com, that use of e-commerce can save us from driving to the local bookstore, and, hence, save energy. We can attend a “virtual” conference using a web-conferencing service such as Webex or Microsoft® Live Meeting and thus save the energy expenditure of an airline flight to the conference, use of a rental car, and all the other energy use that travel entails.

The pursuit of energy efficiency opportunities in data centers is especially important because of the estimated continued rapid growth of direct energy use in data centers and the resulting impact on both the power grid and U.S. industries.

To repeat the theme: We’re all aware of rising energy costs in today’s data centers and the growing concerns over global warming and other environmental issues. These problems have made green IT one of the hottest topics in the IT area. But what exactly is green IT and green computing and how does it affect IT infrastructures? This book provides an outline on the concepts, benefits, and business value of green computing, such as the following:

  • A definition/analysis of green computing and its benefits
  • An overview of green computing solutions
  • The business case for going green
  • Implementation of an energy management solution
  • Why energy efficiency is so important

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