1. Citi
Power, Gas
& Utilities
Conference
June 5-6, 2008
investing for our future.
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2. Cautionary Statements
Regulation G Statement
Ameren has presented certain information in this presentation on a diluted cents per share basis. These diluted per
share amounts reflect certain factors that directly impact Ameren’s total earnings per share. The core earnings per
share (non-GAAP) and core earnings per share guidance (non-GAAP) exclude one or more of the following: costs
related to severe January 2007 storms, abnormal weather, the earnings impact of the settlement agreement among
parties in Illinois for comprehensive electric rate relief and customer assistance, the reversal of accruals made in 2006
for low-income energy assistance and energy efficiency program funding commitments in Illinois, a March 2007 FERC
order, which retroactively adjusted prior years’ regional transmission organization costs, and net mark-to-market gains
or losses from nonqualifying hedges. Ameren uses core earnings internally for financial planning and for analysis of
performance. Ameren also uses core earnings as primary performance measurements when communicating with
analysts and investors regarding our earnings results and outlook, as the company believes it allows it to more
accurately compare the company’s ongoing performance across periods.
In providing consolidated and segment core earnings guidance (non-GAAP), there could be differences between core
earnings (non-GAAP) and earnings prepared in accordance with GAAP for certain items, such as the 2007 Illinois
electric settlement and net mark-to market gains or losses from nonqualifying hedges. Except for the Illinois
settlement, Ameren is not able to estimate the impact, if any, on future GAAP earnings of these items.
Forward-looking Statements
Ameren’s earnings guidance assumes normal weather and is subject to, among other things, regulatory decisions and
legislative actions, plant operations, energy market and economic conditions, severe storms, unusual or otherwise
unexpected gains or losses and other risks and uncertainties outlined in Ameren’s Forward-looking Statements in its
news releases and in the Forward-looking Statements and Risk Factors sections in its periodic filings with the
Securities and Exchange Commission.
investing for our future.
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3. Ameren Introduction
● Regional electric and gas utility
• Missouri regulated generation,
transmission and
delivery business CILCO
• Illinois regulated transmission
and delivery businesses
CIPS
UE
• Non-rate-regulated
IP
generation business
● NYSE-listed under AEE
• Market cap. ~ $9.5 billion
• Component of the S&P 500
investing for our future.
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4. Investment Highlights
● Focused on the Basics - the generation of electricity,
and the delivery of electricity and natural gas
● Strong EPS growth prospects
● Strong, sustainable dividend
• Current yield of ~5.5%
• Focused on future dividend growth
● Commitment to conservative financial management
● Attractive, risk-adjusted long-term total return potential
● Strong underlying value/straight-forward strategy to deliver
shareholder value
investing for our future.
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5. Ameren’s Business Plan
● Achieve operational excellence in all Meaningful
aspects of our business investment
in serving
● Improve our customer service, customers
satisfaction and image
● Demonstrate environmental Fair
leadership return High quality
on service
● Improve regulatory frameworks and investment
returns
● Optimize non-rate-regulated High
generation business customer
satisfaction
● Maximize the value of our
shareholders’ investment
investing for our future.
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6. Financial Outlook
● Near-term regulatory lag
• Rising cost environment (O&M and capital)
• Fuel
• Reliability projects
• Environmental projects
• Depreciation
• Finance costs
• No significant rate adjustments until late 2008 and early 2009
● Significant longer-term earnings growth opportunities
investing for our future.
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7. Financial Outlook Opportunities
Regulated Businesses
● Significant longer-term earnings growth
● Regulated rates reflecting more current costs
• Rate cases filed in Illinois and Missouri
● Increasing rate base investment
● Earning fair returns in regulated operations
investing for our future.
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8. Current Regulated Returns
Support Earnings Growth
● Missouri Regulated Operations(a)
2007 Core (non-GAAP) ROE = 9%
Estimated 2008 Core (non-GAAP) ROE = 7%
• Allowed return in last rate case was 10.2%. Every 1% equals
approximately $50 million of revenues
● Illinois Regulated Operations(b)
2007 Core (non-GAAP) ROE = 5%
Estimated 2008 Core (non-GAAP) ROE = 4%
• Allowed return in last rate case was 10%. Every 1% equals
approximately $27 million of revenues
Based on actual and projected financial results excluding non-GAAP items
(a)
Based on actual and projected financial results excluding non-GAAP items and
(b)
impact of goodwill associated with CILCORP and Illinois Power acquisitions
investing for our future.
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9. Regulated Investment Plans
Support Earnings Growth
Rate Base Growth
($ in Millions)
(Issued and effective as of January 17, 2008)
$9,000
Missouri
Rate Base $8,000
$7,000
Missouri $6,000
Electric(a) $5,900 $5,000
Gas(b) 218 $4,000
Subtotal $6,118 $3,000
$2,000
$1,000
Illinois(b) $0
Distribution $2,120 2006 2007 2008 2009 2010 2011 2012
Transmission 245 $4,500
Illinois
$4,000
Gas 928 $3,500
Subtotal $3,293 $3,000
$2,500
TOTAL $9,411 $2,000
$1,500
At June 30, 2008 (est.) as submitted in current
(a) $1,000
rate case filing
$500
At December 31, 2007
(b)
At December 31, 2006, as submitted in current
(c) $0
rate case filings 2006 2007 2008 2009 2010 2011 2012
investing for our future.
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10. Illinois Rate Filings
● Illinois electric and gas delivery service rate cases filed November 2,
2007
• Decision by end of September 2008
● Current requested revenue increase is $220 million
• 11% ROE; 50% to 53% equity
● Requested rider rate-making mechanisms for electric infrastructure
investment and gas decoupling
• Withdrew request for bad debt expense rider in rebuttal testimony
● ICC staff revenue increase recommendation of $87 million
• 10.7% ROE recommended. Modifications to capital structure
• Recommended disallowances include certain A&G costs, plant additions,
and post-test year reliability expenditures
• Rider mechanism recommendations
investing for our future.
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11. Missouri Rate Case Filing
● Electric rate case filed on April 4, 2008
• Decision by March 2009
● Requested electric revenue increase of $251 million
• 10.9% ROE; 51% equity
● Increase driven by higher costs and increased investment
• Utilized test year ended March 31, 2008
● Requested implementation of fuel and purchased power
cost recovery mechanism
• Did not pursue environmental cost recovery mechanism
• Expect changes to recently adopted rules to be considered by MoPSC
investing for our future.
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12. Financial Outlook Opportunities
Non-rate-regulated Generation
● Position non-rate-regulated business for earnings growth
• Improving plant performance
• Effective marketing, trading and hedging
• Environmental compliance
● Areas significantly impacting future earnings results include future
power, capacity and fuel prices
investing for our future.
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13. Q1 2008 Earnings Reconciliation
$ 0.59
2007 GAAP Earnings per Share
0.09
2007 severe storm-related costs
0.05
FERC order – MISO charges
(0.05)
Illinois contribution plan termination
0.02
Net mark-to-market losses
$ 0.70
2007 Core Earnings per Share (Non-GAAP)
0.06
Missouri rate cases (margin and expense)
(0.05)
Illinois rate redesign
0.16
Other electric and gas margins
0.03
Weather (estimate)
(0.09)
Fuel prices
(0.02)
Plant operations and maintenance
(0.06)
Distribution system reliability
(0.01)
Other labor and employee benefits
(0.01)
Bad debt expenses
(0.01)
Depreciation and amortization
(0.01)
Other taxes
(0.05)
Other, net
$ 0.64
2008 Core Earnings per Share (Non-GAAP)
(0.03)
Illinois electric rate relief settlement
0.05
Net mark-to-market gains
$ 0.66
2008 GAAP Earnings per Share
investing for our future.
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14. 2008 Earnings Guidance
(Issued and effective as of May 2, 2008)
2007 GAAP Earnings per Share $2.98
2007 severe storm-related costs 0.09
Illinois electric rate relief settlement, net 0.21
FERC order – MISO charges 0.06
2007 Core Earnings per Share (non-GAAP) $3.34
Missouri 2007 rate cases (margin and expense) 0.09
Other electric and gas margins 0.77
Weather (estimate) (0.08)
Fuel prices (0.40)
Callaway refueling and maintenance outage 0.06
Plant operations and maintenance (0.19)
Distribution system reliability (0.22)
Other labor and employee benefits (0.06)
Depreciation and amortization (0.06)
Dilution and financing, net (0.13)
Other taxes (0.05)
Other, net (0.07)
2008 Core EPS Guidance Range (non-GAAP) $2.80 – $3.20
Illinois electric rate relief settlement (0.12)
2008 GAAP EPS Guidance Range $2.68 – $3.08
investing for our future.
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15. 2008 Core EPS Segment Guidance
(Issued and effective as of May 2, 2008)
Expected Segment Contribution to Earnings per Share
Missouri Regulated $1.20 – $1.30
Illinois Regulated 0.30 – 0.40
Non-Rate-Regulated Generation 1.30 – 1.50
2008 Core EPS Guidance Range (Non-GAAP)(a) $2.80 – $3.20
(a) The 12 cents per share earnings impact of the settlement agreement among parties in Illinois for comprehensive electric rate relief and customer assistance
and net mark-to market gains or losses from nonqualifying hedges are excluded from non-GAAP guidance.
investing for our future.
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16. Financial Objectives
● Targeting 4% to 6% average non-GAAP EPS growth from
normalized 2007 base to 2010
• Driven primarily by regulated business growth
• Goal of ~$4 per share by 2011 and higher in 2012
● Overall percentage of earnings contribution by regulated business
segments forecasted to increase and approximate current annual
dividend by the end of 2010
● Focused on providing a strong, sustainable dividend
• Current yield of ~5.5%
• Cash flows do not support near-term change
• Focus on future dividend growth
● Targeting long-term total annual shareholder return of ~10%
Bottom line: strong underlying value
Straight-forward strategy to deliver value
investing for our future.
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17. Long-Range EPS Targets
>$4.00
~$3.70
Non-GAAP
Non-GAAP
$3.34
$2.80 - $3.20
Weather-Normalized
$3.24
GAAP
$2.98 GAAP
$2.68 - $3.08
2007 2008 2009 2010 2011 2012
GAAP Non-GAAP
investing for our future.
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18. Appendix
investing for our future.
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19. Ameren Segments
investing for our future.
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20. Missouri Regulated
2007 Electric Revenue Mix
● 1.2 million electric and
127,000 gas customers
18%
• Diverse electric revenue mix
44%
● 10,000 MW generation 38%
• Low-cost 7,000 MW baseload
coal-fired and nuclear fleet Residential Commercial Industrial
● 24,000 square miles Average Residential Electricity
• 2,900 miles of electric Prices (2006)
0.19
19¢
transmission lines 0.17
17¢
15¢
0.15
• 32,000 miles of electric
13¢
0.13
distribution lines 11¢
0.11
● 3,300 employees 9¢
0.09
San Francisco
New York City
7¢
Los Angeles
● Residential rates approximately 40% 0.07
Philadelphia
Cleveland
Wash DC
St.Louis*
Houston
Chicago
5¢
Boston
Seattle
Atlanta
Detroit
0.05
Dallas
Miami
below national average 3¢
0.03
Source: Bureau of Labor statistics
Assumes UE’s 2007 rate increase was in effect in 2006
investing for our future.
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21. Ameren Illinois Utilities
2007 Margin Mix
● Regulated transmission and
distribution company 29%
Electric
• Owns no generation
Gas
71%
● 1.2 million electric and
830,000 gas customers
● 44,000 square miles
• 4,490 miles of electric transmission lines
• 45,000 miles of electric distribution lines
CILCO
• 17,900 miles of natural gas mains
● 2,300 employees
CIPS
● Current bundled electric rates approximate
IP
national average
investing for our future.
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22. Non-Rate-Regulated Generation
● Operate power plants
Edwards
CTGs
• Three legal entities 745 MW
1,140 MW
Coal – 1960
Gas – 2000-01
● Market power and Hutsonville
Duck Creek
related products 150 MW
330 MW
Coal – 1953
Coal – 1976
● 6,300 MW generation
• Low-cost 4,500 MW baseload
coal-fired fleet Coffeen
Meredosia
900 MW
445 MW
● 1,100 employees Coal – 1965
Coal/Oil – 1948
Newton
1,210 MW
Grand Tower CTG
Coal – 1977
510 MW
Gas – 2001
Joppa – 80%
1,000 MW
Coal – 1953
investing for our future.
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23. References
investing for our future.
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24. Fuel Costs
Forecasted numbers are issued and effective as of January 17, 2008
Fuel Costs per MWh(a)
● Fuel costs expected to continue
to increase
● Estimates include all fuel costs $23
$21
$19
(coal, nuclear, natural gas, $17
$15
$14
diesel, emission allowances and
transportation) 2008 2009 2010
● Regulated costs are assumed to Estimated Costs Hedged
be recoverable through a cost
recovery mechanism beginning
in 2009
94% 98%
86%
72%
54%
16%
2008 2009 2010
(a)
Includes contracted and estimated cost increase Regulated Missouri Non-Rate-Regulated
investing for our future.
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25. Non-rate-regulated Generation
Positioned for Earnings Growth
Forecasted numbers are issued and effective as of January 17, 2008
Baseload Generation Baseload Capacity and
(Megawatthours) Availability Factors
40,000 100%
Net Capacity Factor
Forecasted
35,000 Equivalent Availability Factor
Actual
90%
30,000
25,000
80%
20,000
70%
15,000
10,000
60%
5,000
0 50%
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2007 2008 2009 2010
investing for our future.
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26. Solid Market Fundamentals
Forecasted numbers are issued and effective as of January 17, 2008
● Generation hedging policy designed Hedged Power Sales
to reduce risk, but allow for market (excludes capacity-only revenues)
86%
upside Tar
get
● Energy prices 60% Ran
• ATC forward curve for 2008 to 2010 ge
45%
ranged from $48/MWh to $54/MWh
$54
at time of January 17, 2008 $52
$50 MWh
MWh
guidance MWh
• Fundamentals support energy 2008 2009 2010
prices strengthening
Hedged Capacity Sales
● Expect continued development and
tightening of MISO capacity market 28%
• Targeting to sell ~75% 18%
of capacity through 2010 37% 10%
22%
• MISO prices are well below PJM 10%
2008 2009 2010
Embedded in Full Requirements Contract Capacity Only
investing for our future.
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27. 2008 Illinois Electric Rate Redesign
● Illinois electric
rate redesign will
10¢
result in
quarterly
changes in
earnings per
share, but no
annual change 5¢
5¢
Q1 Q2 Q3 Q4
investing for our future.
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28. Ameren Calendar
Illinois
Evidentiary hearings June 9-13, 2008
Briefs July 2008
Proposed delivery service order August 2008 (estimate)
Final delivery service order issued September 2008
Missouri
Submit actual data for forecasted data June 4, 2008
Supplemental direct testimony regarding
updated data June 16, 2008
MoPSC Staff and intervenor testimony filed August 28, 2008
Rebuttal testimony filed by all parties October 14, 2008
Surrebuttal testimony filed by all parties November 5, 2008
Hearings November 17-25 &
December 1-5, 2008
Briefs January 8, 2009
Rate order issued February 2009
New rates effective March 2009
Investor Relations
Q2 2008 quiet period Begins July 7, 2008
Q3 2008 quiet period Begins October 7, 2008
investing for our future.
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29. Major Regulatory Proceedings
Illinois
Web site www.icc.illinois.gov/e-docket
Case # 07-0527
– Interim procurement plan
Case # 07-0585, 07-0586, 07-0587
– Electric delivery services rate cases
Case # 07-0588, 07-0589, 07-0590
– Gas delivery services rate cases
Missouri
Web site www.efis.psc.mo.gov/mpsc/DocketSheet.html
Case # ER-2008-0318
– Electric rate case
investing for our future.
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30. Investor Relations Contacts
● Bruce Steinke 314-554-2574
• Vice President & Controller bsteinke@ameren.com
Manager – Investor Relations
● Theresa Nistendirk 314-206-0693
• Managing Supervisor tnistendirk@ameren.com
Investor Relations
investing for our future.
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