Energy Crisis, Global Warming & IT Industry:

Can the IT Professionals make it better Some Day? A Review:

Muhammad Zakarya1, Izaz Ur Rahman

2& Ayaz Ali Khan

3

1Department of Computer Science,

Abdul Wali Khan University,

Mardan, Pakistan

2Department of Information Systems & Mathematics,

Brunel University,

London, UK

3Department of Computer Science,

COMSATS Institute of Information Technology,

Islamabad, Pakistan

mohd.zakarya@awkum.edu.pk, izaz.rahman@brunel.ac.uk, ayazak12345@gmail.com

ABSTRACT: Global Warming (1GW) and Energy Crisis

(2EC) have forced the researchers at teaching institutes,

organizations, industry, research laboratories and other

academia to study and minimize the power requirements of

digital and electronic devices especially the huge amount of

computers in the global village. Internet Data Centers (3IDC)

are growing to large scale in Information & Communication

Technology (4ICT) industry especially with the development of

Cloud Computing (5CC) platform and their operation cost is

of utmost importance to the energy suppliers. With the rise of

new computing era i.e. Green computing there is a need to

reduce the power consumption in IDC, Information

Technology (6IT) equipments, processing of information and

communication media that will result in lower Green House

Gas (7GHG) emission. This research work will study Green

Computing and will result in solutions to reduce the energy

consumed by IT world. The paper also tries to summarize new

research directions for new researchers in this field.

Index Terms: GW, EC, IDC, ICT, CC, IT, GHG, SG

I. INTRODUCTION:

One of the major issues in IT world is reducing the energy

consumption of computer systems, IT equipments like

CPU, and Inter Data Centers. The energy consumption

should be reduced due to their operational costs. For

example about 25% of the operational cost is spent on air

conditions, backup cooling and power release systems in IT

industry. The entire power dissipation for desktop system

was 160MW in 1992, and in 2001 it was increased to

9000MW [2], still their increase is continuing in a quadratic

fashion. When the power consumption of the system is

increased, afterward it would produce a lot of heat and

warm. And according to the data from two popular vendors

the rate of failure would be doubled as well, when there as

an increase of 100C [3]. When the power consumption of

the system is increased, then it would produce a lot of heat.

Then the cost of the system would also be increased,

because we need a complex cooling system to deal with it

according to the data from Intel Corporation when the

power dissipation is more than 35-40W, then it would need

more than 1W per CPU chip [4]. Dynamic Voltage Scaling

(DVS), Dynamic Frequency Scaling (DFS), Dynamic

Voltage & Frequency Scaling (DVFS), Cluster Server

ON/OFF Scheduling, Dynamic Workload Balancing and

Dispatching are some mechanisms that are studied in

literature for energy minimization and efficiency. Some are

proposed for individual processors and others are proposed

multi-core and distributed type processing i.e. High

Performance Computing (HPC).

The rest of paper is summarized as. In section II, we gave

an introduction to the need for energy efficient IT sector.

Section III is dedicated to the new researchers to find out

research directions in academia and research laboratories.

Finally we conclude and having some proper discussion on

current energy crisis and solutions in following section i.e.

Section IV and V simultaneously.

II. THE NEED FOR ENERGY EFFICIENCY:

Demand for more power and energy have increased the

energy cost and the energy requirements as well. The

production of energy is not sufficient for the usage as there

is a big difference between both ratios. Alternatively energy

distribution centers solve this crisis problem using load

shading mechanism that have an impact on industry and

economy. This is not only our daily life electronic

equipments that we use for our protection against the warm

season, but there are other fields that have forced the

industry, academia and researchers to think for solutions to

978-1-4673-4451-7/12/$31.00 ©2012 IEEE

current energy crisis. Our IT industry is one of the huge

consumers.

III. RELATED WORK & RESEARCH ISSUES:

Information and Communication Technology industry is

well thought-out to be a chief consumer of energy and in

turn energetic contributor to the Green House Gas (GHG)

emissions. Different aspects of IT industry are subject to the

huge power usage. Computer Networks, Huge processing

power & requirements, control of heat generated by

processing speed and other major issues that are specific to

IT industry are playing a major role in power consumption.

A. Networks & Communication

Infrastructure

Computer networks are a major research issue where

network infrastructure and communication protocols are

studied to make them energy efficient and green. In [5],

[6], [7], [8] and [9] the authors have discussed ALR

mechanism in detail. Link rate scaling and link sleep are

two widely proposed ideas, but still leaving a space for

researchers at academia. In link sleep, the media is turned

off when there is no traffic. When to turn on the media, is a

challenging task. Active, idle, sleep and transition are the

major states for link, where transition state is responsible

for all the tasks necessary to wake up the interface from

sleep state. Queue management in this technique is a

tedious job. If the receiver is in sleep mode, packets to be

sent are stored in a queue at sender side. When the queue

occupancy at sender side, falls below a threshold value, the

link is turned on. Different researchers have different

solutions to wakeup the link, when there is a packet to be

delivered or to be received. Some decisions are taken on a

timer expiry and others are base on queue length and

occupancy. The problem with sleep & wake states is the

increasing ratio of packet loss and packet delay, affecting

Quality of Service (QoS). Similarly energy efficiency can

also be achieved by slowing down the link speed i.e. link

rate scaling mechanism. This is similar as DVFS or DVS is

implemented over processors. The IEEE 802.3az standard

defined a low power sleep mode for Ethernet devices,

which are predictable to be appeared in near future.

DVS mechanism can also be implemented over the

communication link. In [10] the authors used the workload

record to envisage the upcoming traffic. Based on that

information, DVS was applied at the communication links.

Such energy efficient computer networks are called Green

Networks and are a challenging task for most researchers at

academia and industry. All networking architectures and

mediums like wired, wireless, WiFi, WiMax and satellite

based communication and networking protocols are needed

to be energy efficient, however researchers have not

actively explored all these for a reduction in carbon

footprint. Co-scheduling of computational, storage and

networking resources, virtualization, redundancy, remote

I/O utilization, code migration, information mitigation and

dynamic circuit management (DSM) are some possible

solutions to enable green networking concept [21].

B. Processing Requirements

Dynamic Voltage & Frequency Scaling (DVFS) schemes

are typically applied to processors to scale the energy

consumption of the processor according to the system load,

and to schedule task set in an energy efficient way [11, 12,

13]. Such implementation is a major research issue over

single-core and multi-core processors. Power aware

scheduling is the cutting edge technique for reducing power

constraints of single-processor and multi-processor systems

i.e. single-core and multi-core technology. Recently a lot of

work has been done on minimizing the energy requirement

of processors. As a drawback of reducing power

consumption of such systems, its response time is increased

unreasonably, hence degrades the overall performance of

the systems. Maintaining the response time and

performance of the processors constant and reducing the

energy requirements of such processor is a challenging

research issue for the Operating System or Real-time

Systems researchers. The two major techniques of

minimizing the processor energy consumption are:

shutdown and slowdown. In case of real-time and other

embedded systems shutdown mechanisms are not suitable

for, as shutting down and re-activating the processing unit

might result in deadline miss. Slowdown mechanisms

through Dynamic Voltage and Frequency Scaling (also

known as DVS) are recognized to be most effectual for

energy minimization in such critical systems and situations.

A number of optimal scheduling algorithms have been

recommended for fixed priority and dynamic priority

scheduling over a fixed quantity of voltage levels. When

some tasks are completed earlier than their deadlines, there

is an opening and opportunity for additional (dynamic)

slowdown that will increase the energy savings. The major

goal of DVS is to reduce energy consumption by as much

as possible without degrading application performance.

C. Cooling Cost

Another issue that the IT industry needs to explore is the

case of multiprocessors where during processing a lot of

heat and energy is produced. To maintain and operate the

processors in a safe way the heat is needed to be controlled.

The goal is to minimize the energy consumption so that the

cooling cost will be reduced. If devices are more energy

hungry, they will execute more jobs as their frequency of

operation will be higher, alternatively will results in more

heat. The basic energy power equation shows that heat

produced by IT equipment is inversely proportional to its

power usage. The quantity of energy (E) consumed in IT

equipments over a time period (T) is equivalent to the

product of the time period T and the average system power

(P) consumed over the time interval T. The relation

between power and energy is shown in equation (Eq. 1).

(Eq. 1)

It is clear from Eq. 1, if we reduce power P or time interval

T, then overall energy consumed is also diminished. When

devices are heated, there performance is also degraded. If

we take the example of CPU, then a cooling fan is used to

maintain its performance and heat to a low level. In High

Performance Computing (HPC) like Cluster Computing,

Grid Computing and Cloud Computing the main issue is

heating and energy conservation. The goal is to minimize

the energy consumption so that the cooling cost will be

reduced. Scheduling periodic and a-periodic tasks such that

the load is balanced among different processors and the

energy consumption is reduced, is a major concern and an

active research topic. Runtime power reduction mechanisms

can also reduce the energy expenditure to some extent [18].

The chief contributors for the total energy consumption in

an internet datacenter are computing devices (Processors)

and cooling system which constitute about 80% of the total

energy consumption. Other systems such as lighting are not

measured due to their insignificant contribution to the total

energy usage [20]. Coefficient Of Performance (COP) is

the ratio of the energy consumed by the CPU to the energy

consumed by the cooling system. COP is an indication for

the efficiency of cooling system on internet datacenters

[20]. The total energy consumed by the cooling system is

given by Eq. 2.

(Eq. 2)

Where (Ec,i) is the total energy consumed by the processing

units and (Eh,i) is the total energy consumed by the cooling

system, and (COPi) is the corresponding Coefficient Of

Performance.

D. IT

Consumption of electrical energy by different IT equipment

like Network Interface Card (NIC) results in GHG

emission. The IT sector is responsible for the fabrication of

roughly 0.75 million tons of CO2 for every 1 TWh energy

consumption [14]. It has been noted that CO2 emission by

IT equipments is doubled in each after 5 years, which adds

to global warming. A decrease of 15%-30% is required in

CO2 emission to decrease the global temperature by less

than 2°C [15]. Computer Systems are at top in power

consumption in academia and organizations, while network

bandwidth is also doubled each after 2 years for fast and

quick applications. Such energy hungry applications

outcome in more IP traffic and more networking

equipments. Consequently, growing energy consumption of

the IT networking sector in general and networking devices,

such as network cards, switches, bridges and routers in

particular [16, 17]. In some surroundings where mobility is

concerned, energy issues are serious and needs to be

addressed appropriately and accurately. In such platforms

power batteries are used that are not trustworthy &

consistent and can make available power for some exact

time & period. Batteries have two major problems, their

lifetime and low battery detection mechanism. Low battery

circuit designing is dependable on cell or battery chemistry,

which can further results in low power alarm. Such issues

are discussed in [25]. Photovoltaic cells, mechanical

vibration i.e. electrostatic and electromagnetic are other

mechanism to provide efficient and lifetime power to

different devices in mobility. Power consumed by analog

signals is greater than power consumed by digital logic.

Power of any digital logic is given by

Pd = Pdyn + Pstat

Where Pdyn (dynamic power) including the power required

for gate transition while (Pstat) static power excluding the

power consumed by gate transition results in total power i.e.

Pd. Hardware designer can use these techniques to design

less power hungry IT equipments and devices [18].

E. Wireless and Mobile Communication

Another interesting field where the IT Experts can

minimize the energy requirements is the mobile

communication or cellular technology. As wireless

communication industry is growing, user demand for new

enhanced features and long battery life are increasing.

Power consumption is a major constraint while designing,

as such devices are battery powered and their life time is

quite small. In mobile phones the most maximum energy is

used by the application itself, with a 40% of energy spent

on audio and video processing. Approximately 20% is used

by the cellular application, and the same amount is spent on

memory and display as well. The remaining peripherals and

I/O units are less energy hungry [23]. Fig. 1 below

summarizes these details. One solution is to use low power

CPUs that eliminates the power loss by diminishing the

frequency of bus transfers and memory accesses. Energy

efficient memory schemes based on concept of locality and

memory split are also considered where mostly used code

or date is kept closer to the processing unit and thus

reducing the energy consumption. Displays are also

considered for less energy. DVFS mechanisms scale down

the voltage supply and the clock frequency to decrease the

system power dissipation. As for batteries are concerned,

the more capacity is there, the more power will be there.

Larger batteries are not suitable for mobile and portable

devices; therefore we have to point on other issues not its

size. Biological fuel cell that are studied in green chemistry,

gives a roadmap to develop mobile batteries that will be life

time charged. Still a lot of research is need in field of

bioinformatics computing [24].

Increasing power costs & demand and the fresh worldwide

focal point on climate change issues has resulted in a sky-

scraping awareness in improving the energy efficiency in

the telecommunications and IT industry [28]. Across the

developed and developing world, wireless communications

has confirmed an obligation. There seems no closing stages

in sight to the propagation of mobile communications

because 120,000 new mobile base stations are deployed

yearly in India.

0 10 20 30 40 50

1

Others

Display

Memory

Cellular

Applications

0 10 20 30 40 50

1

Others

Display

Memory

Cellular

Applications

0 10 20 30 40 50

1

Others

Display

Memory

Cellular

Applications

Fig. 1 Power consumption ratio in wireless devices

A medium sized cellular network uses as much energy as

170,000 homes [27]. The cost of powering a base stations

account for

cost. In view of the fact that mobile base stations guzzle a

greatest fraction of the total energy used in a cellular

system, [27] provides a wide-ranging survey on

mechanisms to attain energy savings in mobile base

stations. They have also discussed a heterogeneous network

deployment based on micro, macro, pico and femtocells

that they have claimed to achieve the goal. Their proposed

Green Cellular Network is still to be considered for a lot of

future research in academia.

IV. KEY SOLUTIONS:

Pakistan is facing from energy crisis since last five years

and no proper action has been taken by the government to

overcome this major issue. If current situation exist, the

problem will rise and will result in a black Pakistan. To

bridge the energy supply-demand gap, government of

Pakistan is evaluating different options including importing

energy from the neighboring countries, as well as elevating

domestic energy production using indigenous energy

sources, such as, hydro, coal, nuclear, solar, and wind. Still

these projects are long term solution. However in short term

solution, there are numerous smarter ways that can

eliminate need of importing energy or adding-on significant

power generation infrastructure. The Smarter ways involve

integration of Telecommunication Technologies, (including

Sensors Networks, and Information Technologies) with

existing Power System .Though marriage of

Telecommunication Systems with Power System, has

created a huge momentum for making the existing Power

System Smarter all over the world, no attention has been

given to the subject in Pakistan so far. The stipulate for

electricity is greater than its supply nowadays. The smart

grid enhances the functionality of the energy delivery

system. This is not impossible since smart grid uses

sensors, communications, computation, and control to make

the system smart and by applying intelligence to it in the

form of control through feed back. In [31], [32] the authors

claimed that to utilize the available resources, customers

also need to be changed, and they need to act smarter.

IT professional can make the situation better through Smart

Technology. A Smart Grid (SG) is an intellectual and

logical electricity network that integrates the actions of all

users connected to it and makes use of sophisticated and

highly advanced information, control, and communications

technologies to save energy, reduce expenditure and

increase reliability and transparency. A smart grid can

reduce energy cost; it makes energy usage efficient that

result in a short term solution for the energy crisis. It also

helps the distribution systems for better energy management

and control. The field of Information & Communication

Technology (ICT) and computer technology can play a

major role in this hazardous situation all over the world. It

is observed that only the production of energy is not

sufficient to reduce the energy crisis. A number of other

issues must be considered. For example the energy

department will be an independent and autonomous body

that will not be affected by any political party. Secondly

commercialization of small turbines is the needed to solve

the current energy crisis situations. Thirdly renewable

energy sources (RES) like solar, wind, thermal and hydro

must be considered as well. Fourthly efficient energy

distribution systems (EEDS) are required to save energy

and to limit the power waste.

It is also observed that most of the organizations and even

people waste energy. Proper symposiums and local energy

efficiency seminars are needed to be arranged to aware

them for energy saving.

Techniques like Adaptive Link Rate (ALR), Dynamic

Voltage Scaling (DVS), Dynamic Frequency Scaling

(DFS), Dynamic Voltage Frequency Scaling (DVFS),

Scheduling jobs to the processors, Static Power

Management (SPM), Dynamic Power Management (DPM),

multi-core processors, virtualization, Storage Area

Networks (SAN), ON / OFF mechanisms and many more

are needed to save energy in data processing. A lot of

literature study has explored such energy efficient

techniques [33, 34, 35, 36, 37].

V. FINAL REMARKS:

Global warming has turn out to be an increasingly

significant item on the global political agenda. In this

regard, ICT have been recognized to be a chief prospect

contributor to overall GHG emissions, having a share of

more than 2% already in 2007 with a strong trend to

increase [29, 30]. Researchers of the green technology have

focused to reduce the energy consumed by the IT industry.

Optimization of the cooling system, efficient processing

using scheduling and mapping, load balancing techniques,

green networks using intelligent routing methodologies and

memory efficiency using data & code migration

mechanism, are considered at different academia, research

centers and laboratories [22]. IT experts are considering

their devices to be less energy hungry and are trying to

reduce the CO2 emission as well. Our processing, storage

and communication requirements are increased day by day.

If the problem is not considered, the current energy crisis

and increase in energy cost will continue to an unreasonable

situation. In [26] the authors have discussed some energy

diminishing techniques for IT experts in terms of IT

equipments. Virtualization, efficient processors, switching

the PC to sleep mode during ideal time, replacement of

CRT monitors with Flat Panel technology, use of flash

memories instead of hard disk drives, two sided printers,

design of such system that took some energy from

renewable energy sources (RES) like solar etc, are some of

the major efficiency techniques.

VI. FUTURE WORK:

It is clear from the literature that the IT industry has played

a major role in current energy crisis and global warming.

needed to consider such issues during the design phase.

Software developers are also needed to write energy

efficient programs during software development. Mobile

communication have also suffered the human health

because the Radio Frequency (RF) pollution generated at

mobile stations have influenced and is hurtful to mankind

and can cause cardiac, neurological, respiratory and other

conditions ranging in brutality from headaches &

exhaustion. Our IT experts are needed to consider such

problems and issues while designing and implementing.

ACKNOWLEDGMENT:

This work is fully supported by Abdul Wali Khan

University, Mardan, Khyber Pakhtun Khwa (KPK),

Pakistan. The author(s) of this article are greatly thankful to

SAIMS i.e. Society for Advancement & Integration of

Multiple Sciences for full guidance and major support.

iFuture is also given a number of credits for arranging

seminars on the subject matter. iFuture is a leading

Research Group at the Department of Computer Science.

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