1. Investor
Meetings
March 2008
investing for our future.
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2. Warner Baxter
Executive Vice President & Chief Financial Officer
Bruce Steinke
Vice President and Controller
investing for our future.
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3. Cautionary Statements
All forecasted numbers in this presentation are issued and effective as of January 17, 2008
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 non-GAAP earnings
per share and non-GAAP earnings per share guidance excludes 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 and a March 2007 FERC order, which
retroactively adjusted prior years’ regional transmission organization costs. Ameren believes this information is useful
because it enables readers to better understand the impact of these factors on Ameren’s results of operations and
earnings per share.
In providing non-GAAP earnings guidance and a non-GAAP earnings growth forecast, there could be differences
between non-GAAP earnings and earnings prepared in accordance with Generally Accepted Accounting Principles
(GAAP) for unusual items, such as the 2007 Illinois electric settlement and the impact of abnormal weather. Except for
the Illinois settlement, Ameren is not able to estimate the impact, if any, on future GAAP earnings of these items.
Therefore, Ameren is not able to provide a corresponding GAAP equivalent for its earnings growth rate forecast.
Forward-looking Statements
Ameren’s consolidated and segment earnings guidance excludes 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 and a March 2007 FERC order, which
retroactively adjusted prior years’ regional transmission organization costs. Ameren’s earnings guidance assumes
normal weather and is subject to, among other things, regulatory and legislative decisions, 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 release issued today 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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4. Ameren Introduction
● Focused on the Basics
● Regional electric and gas utility
• Missouri regulated generation,
transmission and
CILCO
delivery business
• Illinois regulated transmission and
CIPS
delivery businesses
UE
IP
• Non-rate-regulated
generation business
● NYSE-listed under AEE
• Market cap. ~ $9 billion
• Component of the S&P 500
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
generation business High
customer
● Maximize the value of our satisfaction
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 rates reflecting more current costs
● Increasing rate base investment
● Earning fair returns in regulated operations
● Position non-rate-regulated business for earnings growth
• Improved plant performance
• Effective marketing, trading and hedging
• EPS contribution expected to be relatively flat through 2010
• Expectations could change meaningfully depending upon future
power, capacity and fuel prices
• Greater prospects for tightening power markets
• Ancillary and capacity market development
Bottom line: strong underlying value
Straight-forward strategy to deliver value
investing for our future.
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8. 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 ~6%
• Cash flows do not support near-term change
• Focus on future dividend growth
● Targeting long-term total annual shareholder return of ~10%
● Proven and lower-risk strategies to achieve these results
investing for our future.
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9. Long-Range EPS Expectations
2007 to 2010 CAGR of 4% to 6%, continued growth thereafter
>$4.00
~$3.70
Non-GAAP
Non-GAAP
$3.25 - $3.35
$2.80 - $3.20
Weather-Normalized
$3.24
GAAP
$2.90 - $3.00 GAAP
$2.68 - $3.08
2007 2008 2009 2010 2011 2012
GAAP Non-GAAP
investing for our future.
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10. Current Regulated Returns
Support Earnings Growth
● Missouri Regulated Operations(a)
2007 non-GAAP ROE = 9%
Estimated 2008 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 non-GAAP ROE = 5%
Estimated 2008 non-GAAP ROE = 5%
• Allowed return in last rate case was 10%. Every 1% equals
approximately $27 million of revenues
Based on actual and projected financial results excluding non-GAAP items
(a)
Based on actual and projected financial results excluding non-GAAP items and
(b)
impact of goodwill associated with CILCORP and Illinois Power acquisitions
investing for our future.
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11. Regulated Investment Plans
Support Earnings Growth
Rate Base Growth
($ in Millions)
$9,000
Missouri
Rate Base $8,000
$7,000
Missouri(a) $6,000
Electric $5,744 $5,000
Gas 218 $4,000
Subtotal $5,962 $3,000
$2,000
$1,000
Illinois(b) $0
Distribution $2,120 2006 2007 2008 2009 2010 2011 2012
$4,500
Transmission 245 Illinois
$4,000
Gas 928 $3,500
Subtotal $3,293 $3,000
$2,500
$2,000
TOTAL $9,255
$1,500
$1,000
(a)
At December 31, 2007 $500
(b)
At December 31, 2006, $0
as submitted in current rate case filings 2006 2007 2008 2009 2010 2011 2012
investing for our future.
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12. Illinois Rate Filings
● Illinois electric and gas delivery service rate cases filed November 2,
2007
• Decision by end of September 2008
● Requested revenue increase of $247 million
($180 million electric, $67 million gas)
• Electric: 11% ROE; 51% to 53% equity;
rate base = $2.1 billion
• IP residential increase capped at 9.9% in year 1
• Gas 11% ROE; 51% to 53% equity;
rate base = $0.9 billion
● Increase driven by higher costs and increased investment
● Requested rider rate-making mechanisms for electric infrastructure
investment, gas decoupling and bad debt expenses
investing for our future.
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13. Missouri Rate Case Filing
● Expect to file next electric rate case in Q2 2008
• Rate case process in Missouri is typically an 11-month process, but
can be settled earlier
● Increase driven by higher costs and increased investment
● Expect to seek implementation of fuel and environmental cost
recovery mechanisms in next rate case
● Gas infrastructure cost recovery mechanism currently in place
investing for our future.
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14. Non-rate-regulated Generation
Positioned for Earnings Growth
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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15. Solid Market Fundamentals
Hedged Power Sales
● Generation hedging policy (excludes capacity-only revenues)
designed to reduce risk, but allow
86% Tar
for market upside get
● Energy prices 60% Ran
ge
• ATC forward curve for 2008 to 45%
2010 ranged from $48/MWh to $54
$52
$50 MWh
$54/MWh at time of guidance MWh
MWh
• Fundamentals support energy 2008 2009 2010
prices strengthening
Hedged Capacity Sales
● Expect continued development
and tightening of MISO capacity 28%
market
18%
• Targeting to sell ~75% 37% 10%
22%
of capacity through 2010 10%
• MISO prices are well below PJM 2008 2009 2010
Embedded in Full Requirements Contract Capacity Only
investing for our future.
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16. Investment Highlights
● Focused on the Basics - the generation of electricity,
and the delivery of electricity and natural gas
● Strong EPS growth prospects through 2010 – continued growth
thereafter (goal of ~$4 per share by 2011 and higher in 2012)
• 4% - 6% CAGR
• Driven primarily by regulated business growth
• Optimization of existing non-rate-regulated generation/potential tightening
of power markets
● Strong, sustainable dividend
• Current yield of ~6%
• 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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17. Appendix
investing for our future.
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18. Ameren Segments
investing for our future.
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19. Missouri Regulated
Electric Revenue Mix
● 1.2 million electric and (LTM September 30, 2007)
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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20. Ameren Illinois Utilities
Margin Mix (LTM September 30, 2007)
● Regulated transmission and
distribution company 30%
Electric
• Owns no generation
Gas
70%
● 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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21. 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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22. Earnings Guidance
investing for our future.
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23. Major 2008 Assumptions
Missouri Regulated Segment
● Electric rate case expected to be filed Q2-2008
• No impact on 2008 earnings/regulatory lag
● Rising cost environment continues
• Labor, materials, etc.
• Fuel
• Depreciation and financing costs
● Increased investment in rate base and operating expenses to
improve reliability and environmental compliance
● Generation output of 51 million MWh (capacity factor ~83%)
● Callaway nuclear plant refueling in Fall 2008 (25-30 days)
● Normal weather and organic growth
investing for our future.
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24. Major 2008 Assumptions
Illinois Regulated Segment
● Electric and gas rate orders effective October 2008
• Requested 11% ROE
• Bad debt expense, electric infrastructure investment and gas decoupling rate
mechanisms approved
● Rising cost environment continues
• Labor, materials, etc.
• Depreciation and financing costs
● Increased investment in rate base and operating expenses to improve
reliability
● Impact of Illinois electric settlement (5 cents per share) excluded from
guidance
● Normal weather and organic growth
investing for our future.
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25. Major 2008 Assumptions
Non-Rate-Regulated Generation
● Improved plant operations
• Generation output of 33 million MWh vs. 31 million MWh in 2007
• Generation capacity factor of 79% vs. 74% in 2007
● Hedged approximately 86% of output at December 31, 2007
• Expected realized prices of $53.50/MWh vs. $54.50/MWh in 2007
(including energy and capacity sales)
● Ancillary services market revenues of approximately $15 million
(vs. ~$5 million in 2007)
● Capacity market revenues of approximately $40 million
(vs. ~$25 million in 2007)
● Rising cost environment
• Labor, materials, etc.
• Fuel
• Depreciation and financing costs
● Impact of Illinois electric settlement (7 cents per share)
excluded from guidance
● Illinois Monterey coal mine closure
investing for our future.
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26. Major 2008 Assumptions
Corporate
● No new equity issuances planned outside of
DRIP/401k plans (hybrids under consideration)
● Significant levels of debt financings
● No increase in dividend
investing for our future.
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27. 2008 Non-GAAP Earnings Guidance
2007 GAAP Earnings per Share Guidance $2.98
2007 Severe storm-related costs 0.09
IL electric rate relief settlement, net 0.21
FERC order – MISO charges 0.06
2007 Non-GAAP Earnings per Share Guidance $3.34
Missouri 2007 rate case (margin and expense) 0.09
Other electric and gas margins 0.69
Weather (estimate) (0.10)
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 (0.03)
Dilution and financing, net (0.06)
Other taxes (0.05)
Other, net (0.07)
2008 Non-GAAP EPS Guidance Range $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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28. 2008 Non-GAAP Segment Guidance
Contribution to Earnings per Share
2007 2008
Missouri Regulated $1.47 $1.20 – $1.30
Illinois Regulated 0.38 0.35 – 0.45
Non-Rate-Regulated Generation 1.45 1.25 – 1.45
Other 0.04 –
Non-GAAP EPS Guidance Range(a) $3.34 $2.80 – $3.20
(a) The 12 cents per share earnings impact of the settlement agreement among parties in Illinois for comprehensive electric rate relief and customer assistance are
excluded from non-GAAP guidance.
investing for our future.
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29. Capital Expenditure Summary
($ in Millions)
Capital Expenditures
● 65% to 70% of total
capital expenditures in the $2,235
regulated business
segments Target Range:
735
● Approximately 70% of $1,600 to $2,100 per year
non-rate-regulated $1,395
generation capital
400
expenditures due to 425 Non-Rate-Regulated Generation
environmental
Illinois Regulated
compliance 310
● Does not include any Missouri Regulated
1030
potential expenditures
Other/Corporate
related to climate 620
legislation
70
40
2007 2008 2009 2010 2011 2012
investing for our future.
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30. Expected Cash Flow
($ in Millions)
2008
Funds From Operations $1,340
Capital Expenditures (2,235)
Dividends (530)
EEI Dividends (30)
Free Cash Flow ($1,455)
● Negative free cash flow for foreseeable future, an industry-wide
phenomenon
● Cash flow needs expected to be primarily financed with debt and
proceeds from DRIP/401k plan issuances
investing for our future.
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31. 2008 Illinois Electric Rate Redesign
● Illinois electric rate
redesign will result
in quarterly changes 18¢
in earnings per
share, but no annual
change
2¢
7¢
13¢
Q1 Q2 Q3 Q4
investing for our future.
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32. Post-2008 Commentary
● Rising cost environment continues (e.g. labor, materials, fuel,
depreciation, financing)
● Regulatory lag will persist, but will be less significant over time
● Rate cases
• Will be more frequent
• Proposed recovery mechanisms will be granted
• Granted fair ROEs
● No Callaway refueling in 2009 and 2012
● New baseload plant decision for Missouri regulated operations
will need to be made
• Constructive regulatory framework will need to be in place
investing for our future.
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33. Fuel Costs
Fuel Costs per MWh(a)
● Fuel costs expected to continue
to increase
$23
● Estimates include all fuel costs $21
$19
$17
$15
$14
(coal, nuclear, natural gas,
diesel, emission allowances and
transportation)
2008 2009 2010
Estimated Costs Hedged
● Regulated costs are assumed to
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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34. Post-2008 Commentary
● Improved non-rate-regulated generation plant performance
● 2 million MWhs of below-market wholesale contracts at ~$33/MWh
expire in late 2008
● Fundamentals point to more robust energy and capacity prices
compared to current forward curves
● No impact from climate legislation
● No new equity issuances currently planned through 2010, excluding
DRIP/401k plans (hybrids under consideration)
● Focused on strong, sustainable dividend and growing dividend in
the future
investing for our future.
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35. Illinois Settlement
investing for our future.
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36. Illinois Electric Settlement
● Constructively resolved significant legislative, regulatory and legal
uncertainties
• All major parties participated in settlement
● Provides stability to Illinois electric market and provides agreed path for
power procurement
● Significant disincentives for additional legislative action
• Rate relief programs would terminate
• Financial swap agreements could be terminated or renegotiated
• Strong legal position
● No prohibition on ability to file for delivery service
rate increases
investing for our future.
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37. Illinois Electric Settlement Costs
($ in Millions, Except Per Share Amounts)
2007 2008 2009 2010 Total
Ameren Illinois Customers’ Benefit $231.6 $150.4 $100.5 $5.5 $488.0
Contributions of Ameren Companies
Non-rate-regulated Generation 48.2 24.9 15.8 1.1 90.0
Illinois Regulated 30.7 17.9 10.7 0.7 60.0
Total Funding $78.9 $42.8 $26.5 $1.8 $150.0
EPS impact $0.25 $0.12 $0.07 $0.01 $0.45
investing for our future.
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38. Illinois Electric Settlement - Swap
● Ameren Illinois utilities entered into swap agreements with an affiliate to lock-in prices
for a portion of power requirements from 2008 through 2012 at relevant market prices
Period Volume Price per MWh
6/1/08 to 12/31/08 400 MW $47.45
1/1/09 to 05/31/09 400 MW $49.47
6/1/09 to 12/31/09 800 MW $49.47
1/1/10 to 5/31/10 800 MW $51.09
6/1/10 to 12/31/10 1,000 MW $51.09
1/1/11 to 12/31/11 1,000 MW $52.06
1/1/12 to 12/31/12 1,000 MW $53.08
● If any of the following events occur, negotiations may be undertaken so as to preserve
the economic benefits of the swap agreements. If unable to negotiate a settlement, the
swap agreements may be terminated in 60 to 90 days after the event occurs
• A state tax is enacted on electric generation
• A state or federal tax is enacted on or regulation is imposed on greenhouse
gas emissions
• A state law is enacted that eliminates retail electric supplier choice for residential
and small commercial customers
investing for our future.
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39. Power Procurement
● Procurement plan approved ● New Illinois Power Agency (IPA)
by Illinois Commerce to procure power for Illinois utilities
Commission (ICC) for June beginning June 2009
2008 to May 2009 • Process based on acquiring
20
standard market products
Contracted Power Supply
18
(e.g., 7x24 and 5x16 blocks
16
of energy)
MWh (in millions)
14
• RFP process with benchmarks
12
• Third party administrator hired
10
8
by IPA
6
• ICC review and approval
4
• Results of IPA procurement
2
process deemed prudent
0
2008 2009 2010 2011 2012
Auction Financial Swap Contracts
investing for our future.
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40. References
investing for our future.
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41. Ameren Calendar
Illinois
ICC Staff and intervenor testimony filed March 14, 2008
Ameren rebuttal filed April 14, 2008
ICC Staff and intervenor rebuttal May 13, 2008
Ameren surrebuttal May 27, 2008
Written prehearing motions May 29, 2008
Evidentiary hearings June 9-13, 2008
Briefs July 2008
Proposed delivery service order August 2008 (estimate)
Final delivery service order issued September 2008
Missouri
Final environmental rider rules Q2 2008
File electric rate case Q2 2008
Investor Relations
Q1 2008 quiet period Begins April 7, 2008
Q2 2008 quiet period Begins July 7, 2008
Q3 2008 quiet period Begins October 7, 2008
investing for our future.
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42. 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-2007-0002 – Electric rate case (Order issued)
Case # GR-2007-0003 – Gas rate case (Order issued)
Case # ES-2007-0474 – Taum Sauk incident investigation
investing for our future.
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43. 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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