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– Power flow in a typical data center 

– Power flow in a typical data center 

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Electricity usage costs have become an increasing fraction of the total cost of ownership (TCO) for data centers. It is possible to dramatically reduce the electrical consumption of typical data centers through appropriate design of the network-critical physical infrastructure and through the design of the IT architecture.

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Context 1
... office buildings, ICT typically accounts for more than 20% of the energy used, and in some offices up to 70%. Although energy costs typically comprise less than 10% of an overall IT budget, in a few years they could rise to more than 50% according to a 2006 Gartner report. Many large organizations - such as Google - already claim that their annual energy costs exceed their server costs. Between 30% and 60% of the electricity consumed in server rooms is wasted – but integrated planning using current and emerging technologies can reduce power consumption in data centers by 50-80% and required floor space by up to 65%. Performance-wise, computer design has progressed staggeringly well and astonishingly fast but looking at it from a green perspective, the work has barely begun. It takes a lot of energy to create, package, store, and move every 10-20 megabytes of data. Even with energy prices as cheap as they are now, it will soon cost more to power a computer for four years than it does to buy a new one. As 21st century belongs to computers, gizmos and electronic items, energy issues will get a serious ring in the coming days, as the public debate on carbon emissions, global warming and climate change gets hotter. If we think computers are nonpolluting and consume very little energy we need to think again. It is estimated that out of $250 billion per year spent on powering computers worldwide only about 15% of that power is spent computing - the rest is wasted idling. Thus, energy saved on computer hardware and computing will equate tonnes of carbon emissions saved per year. Taking into consideration the popular use of information technology industry, it has to lead a revolution of sorts by turning green in a manner no industry has ever done before. Global carbon emissions attributable to ICT have been estimated at 2% to 2.5% of world totals about the same as the airline industry - and as high as 5- 6% of developed nation totals. McKinsey forecasts that the ICT sector’s carbon footprint will triple during the period from 2002 to 2020. According to the Aug 2007 EPA Report to Congress on Data Center Efficiency, implementing best energy-management practices in existing data centers could reduce their current energy usage by 30%. Up to 70% reduction in energy usage could be achieved by using high efficiency technologies for cooling and power equipment and virtualization techniques. Approximately half or less of the energy used in a data center goes to the IT loads. The other half goes to the network-critical physical infrastructure (NCPI) equipment including power equipment, cooling equipment, and lighting. Figure 1 shows the electrical power flow in a typical high availability data center. Note that all the energy consumed by the data center ends up as waste heat which is rejected outdoors into the atmosphere. Figure 1 is based on a typical data center with 2N power and N+1 cooling equipment, operating at approximately 30% of rated capacity [8]. Electrical power is sold in units of energy called kilowatt-hours (kW-hr), which is the amount of energy delivered in one hour at a power level of 1000 Watts (1 kW). The distinction between power and energy is very important for the economic analysis. Power capacity costs are those associated with the systems that deliver energy and increase with the design power level of the system. Examples of costs driven by power capacity are UPS costs, generator costs, air conditioner costs, and power distribution equipment costs. Energy costs are those associated with the ...
Context 2
... office buildings, ICT typically accounts for more than 20% of the energy used, and in some offices up to 70%. Although energy costs typically comprise less than 10% of an overall IT budget, in a few years they could rise to more than 50% according to a 2006 Gartner report. Many large organizations - such as Google - already claim that their annual energy costs exceed their server costs. Between 30% and 60% of the electricity consumed in server rooms is wasted – but integrated planning using current and emerging technologies can reduce power consumption in data centers by 50-80% and required floor space by up to 65%. Performance-wise, computer design has progressed staggeringly well and astonishingly fast but looking at it from a green perspective, the work has barely begun. It takes a lot of energy to create, package, store, and move every 10-20 megabytes of data. Even with energy prices as cheap as they are now, it will soon cost more to power a computer for four years than it does to buy a new one. As 21st century belongs to computers, gizmos and electronic items, energy issues will get a serious ring in the coming days, as the public debate on carbon emissions, global warming and climate change gets hotter. If we think computers are nonpolluting and consume very little energy we need to think again. It is estimated that out of $250 billion per year spent on powering computers worldwide only about 15% of that power is spent computing - the rest is wasted idling. Thus, energy saved on computer hardware and computing will equate tonnes of carbon emissions saved per year. Taking into consideration the popular use of information technology industry, it has to lead a revolution of sorts by turning green in a manner no industry has ever done before. Global carbon emissions attributable to ICT have been estimated at 2% to 2.5% of world totals about the same as the airline industry - and as high as 5- 6% of developed nation totals. McKinsey forecasts that the ICT sector’s carbon footprint will triple during the period from 2002 to 2020. According to the Aug 2007 EPA Report to Congress on Data Center Efficiency, implementing best energy-management practices in existing data centers could reduce their current energy usage by 30%. Up to 70% reduction in energy usage could be achieved by using high efficiency technologies for cooling and power equipment and virtualization techniques. Approximately half or less of the energy used in a data center goes to the IT loads. The other half goes to the network-critical physical infrastructure (NCPI) equipment including power equipment, cooling equipment, and lighting. Figure 1 shows the electrical power flow in a typical high availability data center. Note that all the energy consumed by the data center ends up as waste heat which is rejected outdoors into the atmosphere. Figure 1 is based on a typical data center with 2N power and N+1 cooling equipment, operating at approximately 30% of rated capacity [8]. Electrical power is sold in units of energy called kilowatt-hours (kW-hr), which is the amount of energy delivered in one hour at a power level of 1000 Watts (1 kW). The distinction between power and energy is very important for the economic analysis. Power capacity costs are those associated with the systems that deliver energy and increase with the design power level of the system. Examples of costs driven by power capacity are UPS costs, generator costs, air conditioner costs, and power distribution equipment costs. Energy costs are those associated with the ...