Exelon (EXC) 8-K This presentation includes forward-looking statements within the meaning of

Exelon Nuclear Update

March 24, 2011

Exhibit 99.1

2

Forward-Looking Statements

This presentation includes forward-looking statements within the meaning of

the Private Securities Litigation Reform Act of 1995, that are subject to risks

and uncertainties. The factors that could cause actual results to differ

materially from these forward-looking statements include those discussed

herein as well as those discussed in (1) Exelon’s 2010 Annual Report on Form

10-K in (a) ITEM 1A. Risk Factors, (b) ITEM 7. Management’s Discussion and

Analysis of Financial Condition and Results of Operations and (c) ITEM 8.

Financial Statements and Supplementary Data: Note 18; and (2) other factors

discussed in filings with the Securities and Exchange Commission

(SEC) by

Exelon Corporation and Exelon Generation Company, LLC (Companies).

Readers are cautioned not to place undue reliance on these forward-looking

statements, which apply only as of the date of this presentation. None of the

Companies undertakes any obligation to publicly release any revision to its

forward-looking statements to reflect events or circumstances after the date of

this presentation.

3

Administration

and

regulators

remain

supportive

of

US

nuclear

plants

“Our nuclear plants have undergone exhaustive study and have been

declared safe for any number of contingencies.”

–

President Obama,

March 17, 2011

“The

NRC

remains

attentive

to

any

information

that

can

be

applied

to

U.S.

reactors.

Our

focus

is

always

on

keeping

plants

in

this

country

safe

and

secure.  As this immediate crisis in Japan comes to an end, we will look at

whatever

information

we

can

gain

from

the

event

and

see

if

there

are

changes we need to make to our own system.”

–

Chairman Greg Jaczko,

March 16, 2011

“Operating nuclear plants in the United States remain safe, with no need

for immediate action.”

–

NRC, March 17, 2011

“The American people should have full confidence that the United States

has rigorous safety regulations in place to ensure that our nuclear power is

generated safely and responsibly…safety remains at the forefront of our

effort to responsibly develop America’s energy resources, and we will

continue to incorporate best practices and lessons learned into that

process.”

–

Secretary Steven Chu, March 17, 2011

Nuclear plant operations and safety will be evaluated to incorporate lessons

learned, but there has not been a rush to judgment

DOE

NRC

White House

4

Japan’s Nuclear Power Plants

Fukushima Daiichi Nuclear Power Station

began operations at Unit 1 in March 1971

4,696 MWe output across 6 BWR

units

All units responded as expected to the

earthquake

Tsunami caused loss of all back-up

power, which is used to cool reactor core

and spent fuel pools

Units 4,5,6 were in cold shutdown for

planned refueling at time of earthquake

and tsunami

Seawater/boron injection into reactor

vessels at Units 1, 2 and 3 continues and

those reactors are now stable

Offsite power restored at all units,

equipment being tested

Source: NEI

5

Exelon’s Plants are Designed to Withstand

Extreme Environmental Hazards

None of Exelon’s plants are in major earthquake zones

Designed

to

withstand

highest

level

of

seismic

activity

for

that

location,

with

additional margin

Regular seismic analyses performed by NRC

Emergency core cooling systems are protected from water incursion,

including water tight doors, elevation of equipment above potential flood

levels and/or special engineered flood barriers (on a site-specific basis)

Fuel tanks are buried underground or enclosed in buildings

Switchgear for emergency operations are elevated above flood levels

All but one of Exelon’s plants are in Illinois and Pennsylvania

Oyster

Creek

(in

NJ)

is

more

than

5

miles

inland,

behind

barrier

islands

•

Tsunamis are extremely rare in the mid-Atlantic

•

Oyster Creek is 23 feet above sea level, while the maximum recorded

high tide on the Barnegat Bay beachfront 5 miles away is 7 feet above

sea level

The NRC requires all nuclear plants in the US to be able to withstand the most

severe natural phenomena historically reported for each plant’s surrounding

area, with a significant margin of error

Tsunami

Flood

Earthquake

6

Exelon’s Nuclear Plants Are Not In Major

Earthquake Zones

Exelon Plant

G Rating

1

Braidwood

0.20g

2

Byron

0.20g

3

Clinton

0.25g

4

Dresden

0.20g

5

LaSalle

0.20g

6

Zion

0.17g

7

Limerick

0.15g

8

Oyster Creek

0.184g

9

Peach Bottom

0.12g

10

Quad Cities

0.24g

11

Salem

0.20g

12

Three Mile

Island

0.12g

7

7

“Defense

In

Depth”

Design

Ensures

Safe

Operations

Even

in

Station

Blackout

Water:

Exelon’s BWRs have at

least six independent ways to put

water into the core in an

emergency

AC Power:

Exelon’s plants get

electricity from at least two

independent power lines

feeding

two independent transformers

Diesel Backup:

Redundant

systems maintain electric power

when electricity is lost from the grid

off site -

multiple backup diesels at

every site

Exelon’s nuclear plants are able to safely shut down and keep the fuel

cooled -

even without electricity from the grid

Diesel Backup

AC Power

8

Emergency Operating Procedures

Emergency Operating Procedures (EOPs) direct operator response to restore or maintain the water level in the

reactor vessel and control containment temperature and pressure for any emergency condition.

Additional modifications and procedure changes have been implemented in response to a postulated loss of all

offsite and onsite AC power under 10 CFR 50.63, the Station Blackout Rule

Severe Accident Management Guidelines (SAMGs) have been implemented to use auxiliary equipment and

alternate system alignments to provide makeup water to the reactor vessel or containment.

Independent of the EOPs and SAMGs, additional procedures and alternate equipment is available onsite to

provide water makeup to the reactor vessel and the spent fuel pools should damage occur to the reactor

building.

This equipment consists of pre-staged pumps, piping, and procedures that can be used independent

of onsite AC power sources.

Designated

onsite

and

offsite

emergency

facilities

are

manned

during

an

emergency

to

provide

additional

input

to

the

control

room

operators.

Both

facilities

are

in

direct

contact

with

the

control

room

and

track

use

of

the

EOPs

and

SAMGs.

Beyond the design, equipment and geography of a nuclear plant, other

emergency response protocols ensure safety is maintained in the event of

one or more unexpected severe events

9

9

Spent Fuel Pools and Dry Cask Storage

Main pool cooling system has redundant backup

Additional backup systems can replace water from

other plant water inventories

Multiple onsite water storage tanks with 80,000 to

500,000 gallon capacity and portable, high

capacity pumps available onsite, along with other

sources,

ensure

spent

fuel

pools

remain

filled

in

an

extreme

emergency

–

even

with

significant

water loss

Elevated pools at 6 plants, at or below grade at 5 others

Pool walls are 3-6 feet of concrete with a sealed stainless

steel liner

Fuel remains in pool for a minimum of 5 years

Exelon generally waits 7-15 years before moving to dry

cask storage

Dry cask storage at Exelon plants:

7 in operation (Dresden, Quad, LaSalle, Byron, Peach,

Oyster, Limerick)

3 more on-line before end of 2013 (Braidwood, Clinton,

Zion)

TMI not until next decade

In An Emergency

Steady State

Spent Fuel Pool

Dry Cask Storage

10

Nuclear Industry Is Responding Proactively

The World Association of Nuclear Operators (WANO) and INPO have

developed this list of actions to evaluate the readiness and capability of

emergency mitigation systems beyond normal plant design basis

1.  Verify capability to mitigate conditions

resulting from beyond design basis events

March 23, 2011

2.  Verify capability to mitigate station blackout

conditions required by station design are

functional and valid

March 30, 2011

3.  Verify capability to mitigate internal and

external flooding events

April 6, 2011

4.  Perform walk-downs and inspections of

important equipment needed to mitigate fire

and flood events and develop strategies to

mitigate any identified vulnerabilities

April 13, 2011

Recommended Action

Due Date

Exelon is fully

responding to each

action item for every

plant in the fleet

11

Plant

Location

Type/

Containment

Water Body

License Extension

Status / License

Expiration

(1)

Ownership

Spent Fuel Storage/

Date to lose full

core discharge

capacity

(2)

Braidwood, IL

(Units 1 and 2)

PWR

Concrete/Steel

Lined

Kankakee

River

Expect to file

application in 2013/

2026, 2027

100%

2012

Byron, IL

(Units 1 and 2)

PWR

Concrete/Steel

Lined

Rock River

Expect to file

application in 2013/

2024, 2026

100%

Dry Cask

Clinton, IL

(Unit 1)

BWR

Concrete/Steel

Lined

Clinton Lake

2026

100%

2018

Dresden, IL

(Units 2 and 3)

BWR

Steel Vessel

Kankakee

River

Renewed/2029,

2031

100%

Dry cask

LaSalle, IL

(Units 1 and 2)

BWR

Concrete/Steel

Lined

Illinois River

2022, 2023

100%

Dry Cask

Quad Cities, IL

(Units 1 and 2)

BWR

Steel Vessel

Mississippi

River

Renewed/2032

75% Exelon, 25%

Mid-American

Holdings

Dry cask

(1)

Operating license renewal process takes approximately 4-5 years from commencement until completion of NRC review.

(2)

The date for loss of full core reserve identifies when the on-site storage pool will no longer have sufficient space to receive a full complement of fuel from the reactor core. Dry cask

storage will be in operation at those sites prior to the closing

of their on-site storage pools.

Exelon

pursues

license

extensions

well

in

advance

of

expiration

to

ensure

adequate

time for

review by the NRC

Exelon Nuclear Fleet Overview -

IL

12

Plant, Location

Type,

Containment

Water Body

License

Extension Status /

License

Expiration

(1)

Ownership

Spent Fuel Storage/

Date to lose full

core discharge

capacity

(2)

Limerick, PA

(Units 1 and 2)

BWR

Concrete/Steel

Lined

Schuylkill

River

Expect to file

application in

2011/2024, 2029

100%

Dry cask

Oyster Creek, NJ

(Unit 1)

BWR

Steel Vessel

Barnegat Bay

Renewed/2029

100%

Dry cask

Peach Bottom, PA

(Units 2 and 3)

BWR

Steel Vessel

Susquehanna

River

Renewed/2033,

2034

50% Exelon,

50% PSEG

Dry cask

TMI, PA (Unit 1)

PWR

Concrete/Steel

Lined

Susquehanna

River

Renewed/2034

100%

2023

Salem, NJ (Units 1

and 2)

PWR

Concrete/Steel

Lined

Delaware

River

In process

(decision in 2011-

2012)/  2016, 2020

42.6% Exelon,

57.4% PSEG

Dry Cask

(1)

Operating license renewal process takes approximately 4-5 years from commencement until completion of NRC review.

(2)

The date for loss of full core reserve identifies when the on-site storage pool will no longer have sufficient space to receive a full complement of fuel from the reactor core. Dry cask

storage will be in operation at those sites prior to the closing

of their on-site storage pools.

Exelon

pursues

license

extensions

well

in

advance

of

expiration

to

ensure

adequate

time for

review by the NRC

Exelon

Nuclear

Fleet

Overview

–

PA

and

NJ

13

Nuclear uprates remain flexible to address changing

circumstances in power markets or regulation

Exelon's Uprate Plan Expenditures

(1)

$0

$100

$200

$300

$400

$500

$600

$700

2008A

2009A

2010A

2011E

2012E

2013E

2014E

2015E

2016E

2017E

0

200

400

600

800

1,000

1,200

1,400

1,600

Megawatt Recovery

MUR

EPU

MW Online (Cumulative)

$150

$250

$475

$550

$475

$600

$625

$425

$200

$ millions

Uprates are unique in that they can be suspended or delayed if economics are no longer attractive

2011 spend is largely for turbine replacement, which we expect will continue as planned

Future spend will continue to be evaluated to ensure the projects still meet economic return hurdles,

but no uprate projects have been cancelled at this time

$50

(1)  Dollars shown are nominal, reflecting 6% escalation, in millions and exclude TMI and Clinton extended power uprates, which are currently under review.  MW shown at ownership.

Note: MUR = measurement uncertainty recapture; EPU = extended power uprate.   Data contained in this slide is rounded.