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The North American Power Grid

By

Diana Lekaj

HSMN625

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University of Maryland University College

July 21, 2013

Abstract

For over 100 years, the North American power grid has been

the backbone supporting the health of our economy, safety, and

quality of life. It has been called the20th century’s engineering

wonder, but at the same time, it is facing a growing threat of

being disrupted by both intended, and collaterally by unintended,

adverse events. A majority of the country’s critical

infrastructure upon which our society so heavily relies depends

on the grid’s readilyavailable and affordable power supply to

function.

Devastation of the power grid, whether due to natural

disaster, a man-made attack, or an unforeseen system failure

would have long-term harmful effects nation-wide.

For this reason, various analysts recommend that policy-makers

and industry experts alike take immediate action to improve the

resilience and protection of such a critical infrastructure.

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Some analysts recommend investing in new and more

sophisticated equipment. Others recommend expanding, modernizing,

and improving current infrastructure by developing the so-called

“smart grid.” This “smart grid” is fully automated and ensures

reliable, efficient, secure, and affordable electricity for

future generations. The new grid will also have increased

capacity and energy storage with real-time outage detection and a

fast response system that would maintain its robustness against

possible all manner of disasters. The cost of this upgrade will

require a hefty investment, but the proposed benefits far

outweigh the costs. An effective public-private partnership is

necessary, a number of reforms and new policies need to be

enacted, and significant challenges will have to be overcome for

this endeavor to succeed.

Introduction

The U.S electrical grid is crucial to the nation’s economic

prosperity, national safety, and quality of life. It is the

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infrastructure that provides the driving force of many processes

at work in American lives every day.Based on the U.S. Department

of Energy (2008), “Our century-old grid is the largest

interconnected machine on Earth, so massively complex and

inextricably linked to human involvement and endeavor that it has

alternatively (and appropriately) been called an ecosystem”

( p.5).

For more than a century, this grid has been a significant

economic driver and the demands on the grid have increased

exponentially. This increase comes as a contribution to higher

living standards, the growing use of personal electronic devices

that require constant recharging, population growth, followed by

bigger houses and bigger electronic home appliances. In addition,

there is a large and constantly increasing number of electronic

vehicles on the road that also utilize this same system (Barrett,

Harner,&Thorne, 2013, p.1).We rely on electricity to heat our

homes, provide our transportation, enable industries to produce

goods for our needs, refine oil, bring lights to our houses,

streets, offices, and without it our lives become burdensome. A

collapse of this infrastructure due to a man-made attack, natural

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disaster, or an unexpected system failure will have long-term and

devastating consequences nation-wide (The National Strategy For

the Physical Protection of Critical Infrastructures and Key

Assets, 2003, p .50).

These consequences would include the loss of power, fuel and

food shortages, disruption in financial systems, TV and

broadcasting limitations, airport closures, traffic jams, and

massive transportation and telecommunications disruptions. When

situations like this occur, particularly when people lose the

power of communication, panic increases and contributes to chaos

like what was experienced in the past with Hurricane Katrina. For

this reason and due to the high inter-dependency among our

critical infrastructures, the U.S government and many field

experts are trying to raise awareness on the increased

vulnerabilities and risks facing the power industry.

The power industry is subject to many conventional risks

such as random equipment failures, extreme weather conditions,

and potentially other emerging unknown threats. Of main concern

for the government, and many experts, is a coordinated physical

and cyber-attack designed to incapacitate components of the power

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grid and disrupt electricity services to government and

commercial facilities, hospitals, military installations, or

other crucial infrastructures (Cauley, 2011, p.46).

Furthermore, while the advancement of technology and

information systems introduced to us to a more convenient way of

life, increases innovation, creativity, productivity and

operation efficiency, it has also increased technological

complexities and created vulnerabilities and risks as well. The

North American power grid has grown tremendously over the last

few decades without a guiding blueprint or overall plan. While

this growth has indeed increased innovation and significant

flexibility, it also made the grid more vulnerable to cascading

failures (Kinney, Crucitti, Reka,&Latora, 2004, p.1). To avoid

such events from happening, and minimize the consequences when

they do happen, policy-makers and industry experts should take

immediate action to improve resilience and increasing the

protection of this critical infrastructure.

The North American Power Grid

The electrical grid has a significant role in driving our

country’s economy. National Academy of Engineering named it as

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the “greatest engineering achievement of the last century” (DOE,

2008, p.5).Undoubtedly, much of the economic and

industrialization progresses accomplished would have been

impossible without the electrical grid. Furthermore, the power

grid is a multi-nodal system that accounts for practically all

the electricity provided to the users in the U.S, Canada, and a

part of Baja California Norte, Mexico. Moreover, the power grid

is also a primary power supplier for our interdependent

infrastructure services such as technology and communications,

water, transportation, and few others upon which most of our

economy relies (Barrett, Harner& Thorne, 2013). To further

understand the importance of our electrical grid, we need to

first understand how it actually works.

The North American power grid is a large complex web of

power sources, power generation stations, transformers,

transmission substations and electrical wires that bring

electricity to our homes and places of work. More specifically,

the grid consists of over 15,000 generators in 10,000 power

plants, and about 360,000 miles of transmission lines to include

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roughly 180,000 high voltage miles totaling over $800 billion in

assets (DOE, 2003 p.3-5).

Most of the electricity is generated in large power plants

by converting primary energy sources such as oil, natural gas,

and coil into electricity, or by splitting atoms (nuclear power

plants), or by falling water typically controlled by

hydroelectric dams. However, before we are able to use coal for

power generation, we need to first mine it and then transport it

to the power plant which is usually done by the use of the rail

system. Likewise, oil and natural gas include extraction

transported by pipelines to a refinery and then to the power

plant through the pipelines, or other forms of transportation.

Therefore, the electrical system is also very dependent on the

transportation and communications infrastructures for the purpose

of power generation. The generated power is then transmitted to

the transmission substations which is like an interconnected web

that transfers electricity from the power plant to the load

centers out along high and low-voltage transmission lines. The

distribution system (substations) draws electricity from the

transmission lines and distributes it to the electricity end-

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users individual houses, public and commercial facilities,

private sector manufacturers and the general public. (Barrett,

Horner & Thorne,2013, p.3).The whole process, and the industry’s

system, is regulated and overseen by various agencies at a local,

state and federal level.

Organizational structure

The North American power grid is managed by the North

American Reliability Corporation (NERC), a non-profit

organization whose mission is to “ensure the reliability of the

bulk power system in North America” (NERC). Furthermore, this

entity is accountable for developing and enforcing reliability

standards and monitoring the bulk power system through user

system awareness. Additionally, this organization is also

responsible for auditing industry owners and operators to ensure

that the critical infrastructure protection standards are met, as

well as for training, educating, and certifying industry

personnel. NERC represents all divisions of the electricity

industry to include private and public utilities in the United

States and Canada. Finally, the NERC is subject to auditing by

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the Federal Energy Regulatory Commission (FERC) and by the

Canadian government authorities (NERC).

The Federal Energy Regulatory Commission (FERC) is an

independed agency that standardizes and oversees all transmission

systems (electricity, natural gas, oil). It also controls

electricity sales at a state level, gas prices, oil pipeline

rates and wholesale electric rates. Rates charged by local power

utilities are usually controlled by state agencies (FERC).

A unique characteristic of the electric energy

infrastructure is that the majority of it is privately owned.

Portions of the infrastructure are owned by federal agencies,

local government, and rural cooperatives. However, the vast

majority is owned by profitable investor-owned utilities.

Additionally, there are also few privately owned independent

power producers (DOE, 2003, p.3-4). Thus, the North American

power grid is owned and operated by a large heterogeneous group

of companies. This group is diverse in many ways. Some companies

differ in size; others vary in capacity or even priorities, which

may present challenges for the electricity sector without proper

security incentives and investments in term of the sector’s

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protection. Some companies may respond more efficiently to

federally mandated security measures, while others may be willing

to only pay for levels of protection that aligns with their

firm’s needs. In spite of these differences, the electricity

industry has proven to be very cooperative in taking proactive

measures to assure system’s reliability and availability. The

Department of Homeland Security along with the Department of

Energy and NERC, are the key players in taking protection

initiatives to keep the infrastructure secure through various

awareness programs. However, individual enterprises are also

actively involved with their local communities in addressing

public safety matters associated with their systems and

facilities. After 9/11 attacks, this sector re-examined their

entire safety guiding principle and established a series of

intra-industry operating groups responsible for addressing

specific security related issues, as well as a utility-sector

security committee responsible for “enhancing planning,

awareness, and resource allocation within the industry”

( NSPPCIKA, 2003, p .51).

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Due to the sector’s heavy dependence on computers and

information systems, the entire sector, with the NERC as their

coordinator, has been collaborating with the Department of Energy

and DHS to create various awareness programs and security

guidelines associated with physical and cyber security. These

include incident information gathering and coordination of daily

briefings with the federal agencies and industry owners and

operators. They have also established threat alert levels for

both types of threats, which involve action-response instructions

for each alert level. Furthermore, they also utilize the US-CERT

National Awareness Program. Industry owners and operators inform

ICS-CERT (Industrial Control Systems Cyber Emergency Team) if

they notice any suspicious activities in their networks. The ICS-

CERT then will post this alert on the US-CERT secured portal for

other CI owners and government agencies to be on the lookout for

similar activities in their systems and take necessary response

actions(NSPPCIKA, 2003, p .51).

Grid’s Risks and Vulnerabilities

Granting that our electric grid is considered a supreme

engineering achievement of the century, it is also a system that

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is constantly facing increased risks. Many analysts think that

part of the reason is because many of the grid’s critical

components are too old. For instance, the American Society of

Civil Engineers (ASCE), on their latest energy infrastructure

assessment, gave this sector a D+ in the American Infrastructure

Report Card. This organization believes since the grid’s system

has progressed over a long period of time too many of its

equipment differ in age and capacity. For instance, near “51% of

the generating capacities of the U.S plants are at least 30 years

old. Most gas-fired capacity is less than 10 years old, while 73%

of all coal-fired capacity is 30 years or older. Moreover,

nationally, 70% of transmission lines and power transformers are

25 years or older, while 60 % of circuit breakers are more than

30 years old” (p.18-19). The fact that some of this equipment is

so old explains why many experts are concerned equipment failures

will cause sporadic failures in power quality and availability.

Furthermore, the limited capacity of this equipment creates

congestion points in the grid which may lead to potential

blackouts.

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Another analyst, Prawdzik (2011), notes that while energy

demand in the U.S has increased in the last two decades,

investments in capacity and transmission have declined. According

to this analyst, “since the 1990s,domestic electricity demand has

risen over 25 percent while energy challenges while construction

of transmission facilities has decreased by about 30 percent”

(Prawdzik,2011, p.41). According to Prawdzik (2011), if this

trend continues, the North American electric grid will be facing

a range of major issues in maintaining affordability of the

electricity supplying the near and long term future. Conversely,

if the demand for electricity continues to grow faster than

supply then the probability for more and larger power blackouts

also increases. Due to the complexity of the interdependencies

among our critical infrastructures, a disruption of a vastly

interconnected area such as electrical power will have cascading

effects to our economy by impacting all other infrastructures as

well. The August 2003, “blackout in portions of the Northeast and

Midwest U.S and Canada, caused an estimated loss of $6 billion in

the United States only” (Barret,Harner,&Throne 2013, p.7). This

disruption affected around 50 million people with the outage

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lasting approximately two days in a majority of places in the

Northeast of U.S and Canada (Simonoff, Restrepo,& Zimmerman,

2007, p. 547).

Hazards also come from natural disasters like flooding or

tsunamis which can cause unforeseen cascading effects for our

interdependent infrastructures and economy. This was proven with

Japan in March of 2011, when the largest tsunami in the recorded

history hit the country’s nuclear power generation capabilities

in Fukushima. The consequences were power disruptions that

affected global manufacturing and caused the global economy

billions of dollars of production in industries ranging from

consumer goods to automobiles. Besides the large-scale economic

impact, this disaster caused the deaths of many Japanese people.

Furthermore, hazards also occur due to weather changing patterns

such as major storms and the prolonged periods of extreme hot or

cold weather temperatures. Situations like this can push the grid

beyond its design limitations, which can result with unpredicted

cascading effects (Barrett, Harner, & Thorne, 2013, p.8). On the

other hand, Gerry Cauley, president and CEO of the NERC claims

that the good news is that in the past, the power industry has

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been successful in achieving resilience in responding and

recovering from routine disruptions such as wind storms,

tornados, hurricanes, thunderstorms and minor substation

failures. Mr. Cauley further explains that the power grid “is

typically designed with sufficient redundancy to manage planned

and unplanned equipment outages” (P. 48). However, not all

analysts are as convinced that the grid’s resilience capabilities

extend to responding and recovering from emerging cyber and

physical threats. A group of researchers at Penn State

University, in their research titled Modeling Cascading Failures in the

North American Powergrid, explain that despite the fact that the

North American power grid is reasonably secure and robust against

random equipment failures, the system remains very fragile in a

way that a targeted attack upon the few key nodes, such as

substations with high-load and high-degree, would have

significant impact to our grid and reduce its efficiency by 25%.

According to the researchers, transmission vulnerability requires

immediate and serious attention by government and industry

executives “so that proper cost effective measures can be

developed” (Kinney, Crucitty, Reka, &Latora, 2005, p. 5).

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Another important threat facing the electrical grid, with a

potential of creating large scale chaos, is that of malicious

actors. Unlike damages from natural disasters where grid parts

can be replaced in a matter of days, a coordinated physical or

cyber-attack could incapacitate some of the grid’s main

components that could take months or even years to replace.

Although physical attacks are less likely to happen they must be

considered during protection measures contingencies.

Conversely, government officials report that cyber intrusion

activities targeting U.S networks have been increasing in the

last few years primarily due to easy and inexpensive internet

access. Attacks of this nature can come from domestic and foreign

hackers, other nations, and various terrorist groups. There are

no border boundaries for cyber space attackers, and attacks of

this nature can be launched from anywhere in the world. There

have been numerous recorded attempts to break into the SCADA

(supervisory control and data acquisition) control systems that

run large power plants. In a few cases, hackers were able to

penetrate the grid’s operational system, but fortunately were

prevented in time before being able to cause any significant

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damage to the system (Perrow, 2007, p .213-215). Cyber threats

may also be deliberate attacks such as industrial espionage or

another government’s cyber spies. In April of 2003, the U.S cyber

experts found out that “China and Russia penetrated the U.S

electrical grid system and left behind software packages capable

of destroying system components” (Prawdzik, 2011, p.42).In fact,

U.S intelligence officials claim these governments have attempted

to map out the U.S infrastructure numerous times in the past, and

according to the DHS, cyber intrusions into the grid’s system are

increasing. Given the significance of the North American power

grid to our society, the growing numbers of cyber-attacks also

present a risk to our national safety and security. For this

reason, and because the North American power grid faces a number

of emerging risks and challenges in the future, various experts

suggest that the industry and policy-makers take immediate action

to address these challenges(Prawdzik, 2011,p.42).

Recommended Solutions

To address these challenges, Gary Cauley at NERC recommends

applying resilience principles— as outlined in the National

Infrastructure Advisory Council (NAIC) report to the White House

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in October 2010—as the most effective approach in fighting

against adversaries. He further explains that applying resilience

means demonstrating proactive readiness regardless the nature of

the threat. It means being able to mitigate consequences and

restore critical services in real time. The NAIC report, in which

Cauley participated in drafting, recommends: “1) a national

response plan that clarifies the roles and responsibilities

between industry and government; 2) improved sharing of

actionable information by government regarding threats and

vulnerabilities; 3) cost recovery for security investments driven

by national policy; and 4)a strategy on spare equipment with long

lead times, such as electric power transformers” (Cauley, 2011,

p.46).In addition, Cauley suggests that resilience should not be

viewed as only a theoretical model to apply throughout the whole

industry. He contends that its principles should be adopted by

each organization that owns or operates a critical infrastructure

facility.

Finally, to ensure robust and resilient electricity

infrastructure Cauley recognizes a need to enhance situational

awareness and communication among the industry and government in

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a timely and reliable secure information exchange. This includes

a need to conduct coordinated training and emergency response

planning among both entities. Finally, there is a need to ensure

an understanding of key interdependencies and cooperate with

other critical infrastructure sectors in assessing the major risk

impacts, identifying opportunities to improve resilience, and

recovery capabilities.

Mr.Cauley’s approach of focusing on the grid’s resilience

and enhancing collaboration and communication towards an

unprecedented level among the private sector and government is

crucial for protecting our infrastructure; however, he does not

provide clear instructions on what requirements are required for

a more resilient system. He does not state what available

technologies we should employ to upgrade and modernize

electricity delivery system, recover transmission congestions,

and how to address various issues in system planning and

operation. Cauley also recommends investing in spare equipment

with long lead times which is a must to enhance resilience.

However, this also requires investing in other basic solutions

such as substitutable parts for main capital equipment as well as

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investing in the latest technologies to enable energy storage for

use in surge capacity during disruption periods. Certainly, using

the principles of systemic resilience to ensure the system

continues operating, regardless of the nature of the risk, is a

way to ensure reliable, efficient, secure, and affordable

electricity for future generations. The joint training and

emergency response plans he recommends are undoubtedly very

valuable in preparing various departments to respond in a time of

crisis, but there should also be a focus on how to build a grid

that is not as vulnerable. The grid must be able to keep pace

with rapidly growing technological information and adapt to

future changes.

Increasing interoperability of the four slightly

interconnected grids (Eastern interconnection, Western

Interconnection, Texas Interconnection, Quebec Interconnection)

is an option recommended by Barrett, Harner, &Thorne (2013). An

optimal solution would be to increase power sharing capacities

for other grids allowing them to share large amount of power in

times of an extended disruption to any of the single segments of

the North American power grid. This means having the remaining

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grids share their power across with the affected power grid. If

achievable, this solution would potentially limit any cascading

failures from shutting off the power supply for the entire

nation. However, this power sharing still will not have the

ability to account for providing power for every single user on

the system. There are still holes in this potential solution due

to the expansiveness of the grid.

To improve the grid’s structural vulnerability, Researchers

at Penn State University present two cost effective options for

the government to consider. One includes “reducing the load upon

the highly loaded nodes by building more transmission substations

and controlling the spread of the cascade or second by producing

more power on a local level via environmentally methods”

(p.5).Reducing the grid’s vulnerability at the transmission and

distribution level is indeed important for addressing issues

because the accurate improvements lead to other important

improvements. These improvements will incur a significant cost,

but also create important gains. Increasing the redundancy and

capacity of the grid’s current structure, and decreasing

dependence on transmission by adding power generation, will

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minimize the effect of potential power outages on the population,

and perhaps save $25 to $ 185 billions of dollars annually that

blackouts cost the economy. However, this solution does not

necessary solve all problems of the electric infrastructure. The

power grid is in need of a solution that modernizes and upgrades

the entire electricity infrastructure. The power grid needs a

properly designed infrastructure that also allows for additional

security against any nature of threats, and a grid that provides

affordable, reliable, and efficient electricity at all times. It

must be a power grid that is able to provide secure services to

all users.

To achieve this, experts at the Department of Energy

recommend modernizing and expanding the electric system by

building a more resilient grid through a smarter grid. This

vision of the future power system will be built based on the

existing footprint with the same components the system uses

presently for power delivery. The new upgrades will include

transition to many new technologies and mechanisms comprised of

distributed intelligence and energy resources which will increase

energy efficiency, security and quality of the existing system,

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and will also allow the development of a new structural design

for the grid.

The smart grid, “Grid 2030” as named by Department of Energy

experts, is a “fully automated power delivery network ensuring a

two-way flow of electricity and information between the power

plants and appliances and all points in between” (DOE, 2003,

p.17).The smart grid will have the ability to remotely monitor

and collect electricity generation, consumption, and transmission

data in real time and integrate this data to modulate the levels

of power being produced and distributed. It will also have the

ability to make computerized decisions as to how to most

efficiently manage the grid infrastructure.

Besides being able to manage and modulate the daily use of

the electricity, the smart grid will also be able to determine

the time and location of the problem when it occurs.

Additionally, the benefit of this solution is that customers are

able to see the cost of peak hour usage through the use of a

smart reader which gives them an opportunity to reduce the

electricity consumption during these hours. Furthermore, the use

of new electrical technologies will enable electricity storage at

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the power plants and at various points in the distribution

system, which can be used for surge capacity during disruption

periods. This would require replacing and connecting new smart

meters, installation of new sensors at the power plants and

through the transmission lines, and adding new readers that will

need upgraded information systems to manage the new data and

remotely control other crucial parts of the system. While the

gains from creating a smart grid infrastructure will undoubtedly

be enormous for the economy, the estimated costs to this change

will range from several hundred billion to $1.4 trillion over the

next ten years. However, this cost can be put in perspective

when we consider that the power disruption costs will drop by an

estimated $49 billion a year. The smart grid is also flexible

enough to accommodate electricity delivery from renewable

technologies such as wind, hydro, as well as fuel-efficient power

generation technologies like combustion turbines (DOE, 2003, p.

18-19).

The new smart grid will benefit the nation in number of

ways. An expended and modernized grid will reduce electric system

limitations and allow more future growth, which will in turn

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attract capital and investments for development and support of

new plant equipment. More importantly, the real-time detection of

outages, computerized responses, and fast restoration systems

will increase the grid’s security and reduce its vulnerability to

potential physical attacks. Better information incorporation and

innovative technologies will also include better cyber-security

safeguards. The expanded use of distributed energy resources will

provide electricity to all other key infrastructures and will

enable their operability even during a crisis. Finally, the

choice of electricity will also expand and every user from

homeowners to factories, manufacturers and businesses will be

able to tailor their energy supplies to meet their individual

needs(DOE, 2003, p.20).

Conclusion

The North American power grid is the greatest engineering

machine of the 20th century, but is facing a range of upcoming

challenges. Issues such as capacity, vulnerability, security,

efficiency, and reliability limits the aging grid in meeting the

nation’s needs and increased energy demands. It requires

operational changes and significant capital investment in the

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upcoming years. At present, the power grid is fairly effective in

energy producing and soundly reliable when it comes to routine

events and disruptions. However, our energy demands are

increasing, and also changing, and we want more electricity more

often from various sources. More importantly, the power grid is

facing the growing risk of being disrupted by adverse events. For

this reason, and due to the nature of our nation’s shared

dependence on the power grid, building a grid capable of greater

resilience through a smarter grid appears like the most optimal

solution.

Modernizing and expanding the nation’s electric system is a

substantial and challenging task, but the benefits are worth

investment. An unparalleled level of cooperation among the

industry shareholders and the government is mandatory to ensure a

robust and resilient electricity infrastructure upon which many

of our critical infrastructures depend. A number of policy

changes and reforms need to take place to be able to accomplish

this task. Policy guidance defining roles and responsibilities of

each sector is needed to maintain the grid’s security and

reliability. Effective risk management and security enforcement

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procedures should be developed to prevent our grid from possible

terrorist and natural disaster threats.

With the increased capacity and energy storage ability,

real-time outage detection and fast response system, the new

smart grid infrastructure should be robust enough to withstand

any physical and natural disaster threats. However, switching to

a fully automated electric system, using open networking

technologies and communication systems in the transmission,

generation, and distribution of electricity can increase cyber

vulnerability. Proper cyber measures are needed to ensure that

the new infrastructure is highly resistant against any accidental

or deliberate network disruptions. A proper system design from

the start is mandatory for mitigating risks. Consequently,

enhancing situational awareness between the public-private sector

via secure, timely, and reliable information sharing is a key for

addressing related risks. Enforcing cyber security standards and

security procedures industry wide and installing proper hardware

and software designed to protect the system against cyber-attacks

is required to strengthen cyber security. The final step to good

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security is continuous improvement and system monitoring to keep

malicious actors out of the grid’s system.

Finally, an effective public-private partnership and

significant investments are required to improve and protect our

electricity infrastructure. Numerous other challenges need to be

overcome to develop a workable path to get us there. Otherwise,

in the near future we might find ourselves without that constant

electrical power that fuels the light in our homes and streets,

enables our communications and transportation systems, and many

other critical services upon which our society so heavily relies.

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