on the job…
throughout 2008, we remained focused on our customers. We made
significant investments in our energy infrastructure and forged
strong partnerships with our customers and communities, improving
overall reliability and customer satisfaction. through amerenue’s
power on reliability program in Missouri, in 2008 we completed
250 undergrounding projects, burying more than 100 miles of electric
line. We trimmed trees along more than 6,500 miles of overhead
line, tested nearly 100,000 wood utility poles and inspected more
than 8,000 miles of electric line – all to improve customer reliability.
this initiative resulted in a much lower number of outages during
2008 weather events.
In Illinois, targeting the worst-performing circuits and aggressively
trimming trees also yielded significant reliability improvements. Illinois
crews’ performance on gas leak calls – with an average response
time of less than 23 minutes – placed ameren’s Illinois utilities among
the leaders in industry rankings.
In both states, ratings in surveys conducted with customers who
had contact with ameren’s utility companies were among the
highest ever experienced, and ratings of general satisfaction
also improved. across Illinois and Missouri in 2008, our utility
companies can be credited with distinguished performance, reducing
the frequency of service interruptions and per-customer outages by
15 percent since 2004 to earn a top-quartile industry ranking.
on your side…
environmental stewardship is a cornerstone of performance
leadership at ameren. over the years, our power plants have been
industry leaders in reducing emissions by piloting new technologies
and investing in research. In 2008, we began installing scrubbers –
sophisticated emissions-reduction equipment – at three plants. these
new, state-of-the-art controls are expected to eliminate almost all
sulfur dioxide emissions at these facilities.
at amerenue, a comprehensive integrated resource planning
process calls for the combination of energy efficiency initiatives and
renewable resources as the best way to delay the need for building
large generating plants. In executing this plan, we are launching
aggressive initiatives to help customers use energy more efficiently.
a range of customer programs are aimed at helping customers
change their approach to using energy, with a goal of saving
540 megawatts of generation by 2025 – the equivalent of a mid-sized
coal-fired plant. amerenue has also committed to add wind power
to its generation portfolio and continues to sponsor and promote a
voluntary renewable energy program for electric customers.
Illinois law has set aggressive annual energy efficiency savings
goals. In 2008, we began offering incentives on electric energy-
efficient systems to our Illinois customers, and ameren’s Illinois
(Photo at right) Jeremy Dyer, Director of
Operations C-Store Division, Niemann
utilities have also created actonenergy.com, a dynamic new Web
Foods, right, discusses energy efficiency
with Rusty Tribe, an Ameren Illinois
site to provide energy-saving advice and program information.
utilities’ ActOnEnergy™ representative.
ameren’s purchase of renewable energy credits in Illinois also
With a three-year electric and natural gas
budget of $100 million, ActOnEnergy is
demonstrates the company’s commitment.
an incentive program for Ameren Illinois
utilities’ electric and natural gas distribu-
tion customers. Niemann Foods received
more than $212,000 for projects that
will make 27 Illinois grocery stores
more energy efficient.
providing energy savings options
and protecting the environment
even though the current economic environment has created
challenges for our industry and our company, we have plans in
place to stay on strategy. that strategy calls for investing in our
Illinois and Missouri regulated businesses to deliver safe, reliable
and affordable energy in an environmentally responsible manner.
our strategy also calls for optimizing our existing non-rate-regulated
generation assets. together, these initiatives should deliver solid,
long-term value to our shareholders.
also key to our strategic plan is our concept of the cycle shown
on this page: that cycle begins with prudent investments in
HIgH infrastructure. Making these investments helps us improve service,
which, in turn, leads to higher customer satisfaction. Improved
service and satisfaction should translate into fair treatment by our
regulators. Better regulatory treatment should result in improved
returns on investment for our regulated electric and natural
gas operations – bringing returns to levels that are necessary to
cost-effectively fund further infrastructure investment. all this
should lead to a continuation of this cycle and long-term benefits
to our shareholders.
my fellow shareholders
the theme of our 2008 report is simple: We are on the job,
on your side and focused on our strategy.
the evidence of our progress on these initiatives is plentiful,
from improved reliability statistics to higher customer
satisfaction ratings, from strong power plant performance
to much-needed rate increases for our regulated operations
both in Illinois and Missouri.
I will address these later, but one of our most critical 2008
accomplishments is that we acted strategically to respond to
the dramatic economic downturn, volatile commodity markets
and unprecedented strains in capital and credit markets.
We took timely, prudent actions to increase our liquidity and
enhance our financial flexibility, accessing the capital markets
and significantly reducing our 2008 and projected 2009 spending.
We put in place plans to slash projected capital and operating
expenditures by approximately $800 million. We reduced
executive management salaries and incentive compensation
opportunities and established firm controls on headcount. We
have always tightly managed our operations, maintenance and
administrative expenses, but we are taking it to a new level.
Ameren’s Executive Leadership Team: (From left) Adam C. Heflin, Senior Vice President and Chief Nuclear Officer,
AmerenUE; Donna K. Martin, Senior Vice President and Chief Human Resources Officer; Daniel F. Cole, Senior Vice
President, Administration and Technical Services, Ameren Services; Scott A. Cisel, President and Chief Executive Officer,
AmerenCilCO, AmerenCiPS and AmereniP; Gary L. Rainwater, Chairman, President and Chief Executive Officer;
Andrew M. Serri, President, Ameren Energy Marketing; Thomas R. Voss, Executive Vice President and Chief Operating
Officer, President and Chief Executive Officer, AmerenUE; Charles D. Naslund, President and Chief Executive Officer,
Ameren Energy Resources; Warner L. Baxter, Executive Vice President and Chief Financial Officer, President and
Chief Executive Officer, Ameren Services; Richard J. Mark, Senior Vice President, Energy Delivery, AmerenUE;
Martin J. Lyons, Jr., Senior Vice President and Chief Accounting Officer; Steven R. Sullivan, Senior Vice President,
General Counsel and Secretary; and Michael L. Moehn, Senior Vice President, Corporate Planning and Risk Management,
as part of these efforts, ameren’s Board of Directors companies, as compared to the 88 percent paid out
reduced the common share dividend level by by ameren in 2008.
39 percent in early 2009. your board did not make
By setting a new, more realistic level, we can retain
this decision lightly. ameren’s directors realized
approximately $215 million a year. this additional
that the corporation was faced with the prospect of
cash will help us enhance reliability, meet our
abandoning a strategic plan that we firmly believe
customers’ expectations and grow our regulated
will deliver long-term value to you, our investors.
businesses. It will also reduce our reliance on
Had we not reduced the dividend, we would have
dilutive equity financings, enhance our access to
been forced to turn to high-cost financings to
the capital and credit markets and drive solid, long-
support the execution of that plan.
term earnings-per-share growth.
AmerenUE is installing weather stations on existing AmerenUE poles in
key locations throughout the region to measure temperature and wind
speed, among other variables. AmerenUE joined Saint Louis University’s
Department of Earth & Atmospheric Sciences to create Quantum
Weather™, a highly precise weather monitoring, forecasting and response
system that improves efficiency and speeds up power restoration.
We are FoCuseD on DelIverIng
some background on the dividend: the previous
level was established at a time when ameren’s saFe, relIaBle anD aFForDaBle
earnings were fully regulated and more predict-
energy, WHIle aCHIevIng solID
able. In 2008, almost 60 percent of ameren’s
returns. groWIng our InvestMent
earnings came from its non-rate-regulated genera-
In our regulateD BusInesses WIll
tion business. these earnings are subject to wide
InCrease CustoMer satIsFaCtIon
fluctuations based on market-driven power prices.
tHrougH exCellent servICe.
Continued dependence on this volatile earnings
stream cannot support a large dividend, and our
dividend was sizeable. In recent years, ameren’s
In the end, this action will make ameren stronger
annual dividend payout has totaled over half a
and more nimble – able to access the capital
billion dollars – a payout ratio that was among the
markets on more favorable terms.
highest in the industry and the nation.
More importantly, we can use these incremental
our adjusted dividend level provides us with a more
funds to continue to pursue the following straightfor-
sustainable payout ratio, based upon earnings
ward, long-term business strategies to deliver solid,
primarily from our regulated businesses. It also
long-term value to you, our shareholders:
puts our new dividend payout ratio squarely in line
with ratios of 50 to 60 percent of earnings for peer
• A Commitment To Investing In Our Illinois In 2008, we also worked to balance the need to
and Missouri Regulated Businesses. We are invest in regulated delivery and generation infra-
focused on delivering safe, reliable and affordable structure with the need to provide reasonable rates.
energy, while achieving solid returns. growing In addition, we aggressively sought recovery of
our investment in our regulated businesses these prudent investments to improve our returns.
will increase customer satisfaction through
• Building Constructive Regulatory Frame-
works. Being “on” means recognizing the impact
In 2008, we succeeded in doing just that. on the regulatory decisions have on earnings and credit
delivery side of our business, reliability improved, ratings that affect our ability to cost effectively raise
and customer satisfaction survey ratings rose. capital and invest in our businesses. In both Illinois
For generating stations across Ameren’s service
territory, the Performance Monitoring Center
continuously monitors plant equipment performance
through pattern recognition software tools and
real-time support. The center provides early stage
notification of any equipment degradation or pending
equipment failure to avoid extended outages that
could hurt power plant availability.
amerenue’s power on reliability program and Missouri, we have worked hard to achieve
contributed to a much lower number of outages constructive regulatory outcomes, given our need
during storms. Both the Illinois and Missouri to update rates to levels that reflect today’s much
delivery companies earned top-quartile industry higher costs. our three Illinois electric and natural
rankings by reducing service interruption frequency gas delivery companies were authorized to raise
– a key reliability measure. rates by $161 million, effective october 1, 2008.
amerenue received a $162 million electric rate
our focus on achieving operational excellence at increase in Missouri, which took effect March 1, 2009.
our regulated generating plants has also yielded However, even with this recent increase, amerenue
strong results – with our Callaway nuclear plant rates remain well below the national average.
leading the way. In 2008, Callaway completed
a record run of 520 consecutive days – and its the most recent Missouri rate case also granted
shortest refueling and maintenance outage ever. approval for recovering fuel and purchased power
our coal-fired plants also performed well, with costs on a timely basis. By offering greater stability
another year of solid availability. one notable mile- of earnings and cash flows, this provision bolsters
stone: labadie power plant in Missouri generated our ability to continue to raise capital and invest in
more than a half-billion-megawatthours – one of our utility infrastructure.
only a few coal-fired plants in the nation to achieve
In 2008, Core earnIngs at
• Optimizing Our Existing non-Rate-Regulated
generatIon operatIons rose
Generation Assets. In 2008, core earnings at
alMost 11 perCent BeCause tHe
our non-rate-regulated generation operations rose
plants stayeD On – IMprovIng
almost 11 percent because the plants stayed
output anD MargIns.
on – improving output and margins.
unfortunately, power and fuel markets have recently For all these reasons, we are focused on this issue.
exhibited extreme price volatility. However, our We have been actively working to frame reasonable
prudent hedging policies are expected to preserve legislation and regulation, while we have acted to
value in 2009 and beyond. as we manage our address climate change. our efforts range from
investment in non-rate-regulated generation participating in research projects on clean coal and
A new scrubber (left) is being installed at our Duck Creek Power
Plant in Canton, near Peoria, Ill. (above). Slated for completion in
2009, the scrubber operates like a chemical plant and, along with
an existing selective catalytic reduction system, will dramatically
reduce sulfur dioxide and mercury emissions, positioning this non-
rate-regulated generating plant to comply with state and federal
clean air regulations.
operations, we will continue to closely monitor carbon capture storage technologies to increasing
market movements and the regulatory landscape. operating efficiencies at our nuclear and hydro-
In 2008, we began to install state-of-the-art environ- electric plants.
mental controls at some of our non-rate-regulated
ameren is also “on” when it comes to encouraging
coal-fired plants to extend their lives in the face of
energy efficiency. In early 2008, amerenue filed
increasingly stringent federal and state emissions
an integrated resource plan with the Missouri public
service Commission detailing how the company
• Demonstrating Environmental Leadership. expects to supply electricity in coming years. after
We continue to maintain an active presence in a year-long process involving dozens of meetings
discussions related to the need to address climate with stakeholders and intensive analysis, the
change by reducing greenhouse gas emissions company filed a preferred plan that calls for
from our coal-fired plants. our current analysis increasing efficiency initiatives and renewable
of various policy scenarios now being debated in energy development. Both in Illinois and Missouri,
Washington shows that, if implemented, they could we are launching a number of programs aimed at
cause household costs and rates for electricity helping customers reduce energy use. the ameren
to rise significantly. the Midwest economy is Illinois utilities have raised customer energy aware-
especially vulnerable to economic dislocation given ness with an award-winning actonenergy Web site
its reliance on coal-fired power. (www.actonenergy.com).
In Missouri, amerenue plans to add at least growth target of at least 5 percent. Coupled with
100 megawatts of wind power by 2010 and antici- the new common dividend rate, this would provide
pates up to an additional 225 megawatts by 2020. competitive, long-term total return potential. even-
the company is working to supply electric genera- tually, our goal would be to grow the dividend level
tion from wind and landfill gas, while participating in as our earnings from rate-regulated operations
studies on potential biomass fuel sources, looking increase and our overall cash profile improves.
into hydroelectric generation facilities on local rivers
We are confident that execution of this plan will
and investigating development of solar generation.
deliver solid, long-term returns for our shareholders
amerenue has also launched a voluntary renew-
as the economy and energy markets recover. We
able energy credit customer program, which in
understand that you – our owners – depend on us
2008, was named the new green power program
Shown here are the cooling tower and a simulated control room used for
training at AmerenUE’s Callaway Nuclear Plant, where in October 2008,
employees completed a record run of 520 consecutive days, which began
in May 2007. Callaway is one of only 26 of the nation’s 104 nuclear plants
to achieve a record run of more than 500 days.
of the year by the u.s. Department of energy, the to turn challenges into opportunities for sustained
u.s. environmental protection agency and the growth. We have the strategies, the people and the
Center for resource solutions. In Illinois, we are assets to do just that. We are “on” it.
purchasing renewable energy credits.
We want to thank you for your continued support
However, we know this will not be enough. during this difficult period, and we thank our
amerenue expects to need new generation by employees for their dedication and for incorporating
the 2018 to 2020 timeframe. that’s why in 2008 our values in everything they do.
amerenue moved to preserve the option for a
I hope you can attend this year’s annual share-
possible second nuclear unit at its existing Callaway
holders’ Meeting on april 28 at the Chase park
plant site. no decision on building a unit has been
plaza Hotel in st. louis.
made. But by applying for a license to possibly build
a unit, we began the regulatory process and made
the unit eligible for billions of dollars in federal incen-
tives established by the energy policy act of 2005.
gary l. raInWater
CHaIrMan, presIDent anD
ameren is on the path to earnings growth. We
CHIeF exeCutIve oFFICer
expect execution of our strategy to enable us to aMeren CorporatIon
March 2, 2009
achieve a long-term, annual earnings-per-share
Year Ended December 31,
(In millions, except per share amounts and as noted) 2007 2006
results oF operatIons
operating revenues $7,562 $6,895
operating expenses $6,203 $5,707
operating income $1,359 $1,188
net income $618 $547
CoMMon stoCk Data
earnings per basic and diluted share $2.98 $2.66
Dividends per common share $2.54 $2.54
Dividend yield (year-end) 4.7% 4.7%
Market price per common share (year-end closing) $54.21 $53.73
shares outstanding (weighted average) 207.4 205.6
total market value of common shares (year-end) $11,294 $11,099
Book value per common share $32.41 $31.87
BalanCe sHeet Data
property and plant, net $15,069 $14,286
total assets $20,728 $19,635
long-term debt obligations, excluding current maturities $5,689 $5,285
Common equity 48.2% 50.6%
preferred stock, not subject to mandatory redemption 1.4% 1.5%
Debt and preferred stock subject to mandatory redemption, net of cash 50.4% 47.9%
total electric sales (kilowatthours) 107,486 101,015
native natural gas sales (decatherms in thousands) 107,871 108,682
total generation output (kilowatthours) 81,367 81,485
electric customers 2.4 2.4
natural gas customers 1.0 1.0
capacity in Illinois
3,400,000 ameren employees, numbering approximately
9,500, serve approximately 2.4 million electric
electric and natural
gas customers and nearly one million natural gas customers over
Peoria 64,000 square miles in Illinois and Missouri. the
company’s service territory includes a diverse
Springfield base of residential, commercial and large industrial
customers in both urban and rural areas. In
Missouri, we operate primarily as a traditional,
rate-regulated utility with about 10,000 megawatts
of generating capacity. our Illinois operations
10,000 include rate-regulated electric and natural gas
transmission and distribution businesses, as well
capacity in Missouri
as a non-rate-regulated generating business
with a capacity of approximately 6,500 megawatts
of generation. today, ameren’s Missouri company,
amerenue, is the largest electric utility in the state,
Electric Service Territory
while the Illinois operations make ameren the
Electric and Natural Gas
second largest electric distribution company and
one of the largest distributors of natural gas in
total natIve total CapItal
eleCtrIC natural generatIon InvestMents
sales gas sales output
(Decatherms in thousands)
(kilowatthours in millions)
(kilowatthours in millions)
06 07 08 06 07 08
06 07 08 06 07 08
Ameren Corporation and Subsidiaries Officers and Directors
exeCutIve leaDersHIp teaM
Michael L. Moehn*
Scott A. Cisel* Daniel F. Cole*
Gary L. Rainwater
Senior Vice President,
Chairman, President President and Chief Senior Vice President,
Corporate Planning and Risk
and Chief Executive Officer Executive Officer, Administration and Technical
AmerenCILCO, AmerenCIPS, Services, Ameren Services
Warner L. Baxter
AmerenIP Adam C. Heflin*
Executive Vice President
Charles D. Naslund*
and Chief Financial Officer; Senior Vice President and
Donna K. Martin
President and Chief Executive
President and Chief Executive Senior Vice President Chief Nuclear Officer,
Officer, Ameren Energy Resources;
Officer, Ameren Services and Chief Human AmerenUE
President, Ameren Energy
Thomas R. Voss Martin J. Lyons, Jr.
Executive Vice President Senior Vice President
Steven R. Sullivan
Andrew M. Serri*
and Chief Operating Officer; Senior Vice President, and Chief Accounting Officer
President and Chief Executive General Counsel and Richard J. Mark*
Ameren Energy Marketing
Officer, AmerenUE Secretary Senior Vice President,
Energy Delivery, AmerenUE
John R. Fey* Michael L. Menne* Joseph M. Power*
Vice President, Human Vice President, Vice President, Federal
Resources, Business Services, Environmental Safety and Health, Legislative and Regulatory
Vice President, Business Planning
Ameren Services Ameren Services Affairs, Ameren Services
and Controller, AmerenUE
Donald M. Mosier* William J. Prebil*
Karen C. Foss*
Jerre E. Birdsong
Vice President, Public Relations, Vice President, Vice President,
Vice President and Treasurer
AmerenUE Ameren Energy Marketing Regional Operations,
Mark C. Birk* AmerenCILCO, AmerenCIPS,
Michael J. Getz* Michael G. Mueller*
Vice President, AmerenIP
Controller, President, Ameren Energy
Power Operations, AmerenUE
David J. Schepers*
AmerenCILCO, AmerenCIPS, Fuels and Services
Maureen A. Borkowski* AmerenIP Vice President, Energy
Robert K. Neff*
Vice President, Transmission, Delivery Technical Services,
Scott A. Glaeser* Vice President, Coal Supply
Ameren Services Ameren Services
Vice President, Gas Supply and Transportation,
S. Mark Brawley* Shawn E. Schukar*
and System Control, Ameren Energy Fuels and
Vice President, Internal Audit, Ameren Energy Fuels Services Vice President, Strategic
Ameren Services and Services Initiatives, Ameren Services
Craig D. Nelson*
Charles A. Bremer* Timothy E. Herrmann* Vice President, Regulatory Affairs Jerry L. Simpson*
Vice President, Information Vice President, Engineering, and Financial Services, Ameren- Vice President, Business
Technology and Ameren Callaway Nuclear Plant, CILCO, AmerenCIPS, AmerenIP Services, Ameren Energy
Services Center, Ameren Services AmerenUE Resources
Gregory L. Nelson*
Richard C. Cissell* Christopher A. Iselin* James A. Sobule*
Vice President and Tax Counsel,
Vice President, Operations, Vice President, Generation Ameren Services Vice President and
Ameren Energy Generating Technical Services, Deputy General Counsel,
Stan E. Ogden*
Ameren Energy Resources Ameren Services
Kevin DeGraw* Vice President, Customer
Vice President, Stephen M. Kidwell* Service and Public Relations, Bruce A. Steinke
Corporate Project Risk Vice President, AmerenCILCO, AmerenCIPS, Vice President and Controller
Management, Ameren Services Regulatory Affairs, AmerenUE AmerenIP Dennis W. Weisenborn*
Fadi Diya* Mark C. Lindgren* Ronald D. Pate* Vice President,
Vice President, Vice President, Corporate Vice President, Regional Supply Services, Ameren
Nuclear Operations, AmerenUE Human Resources, Operations, AmerenCILCO, Services
Ameren Services AmerenCIPS, AmerenIP
Ronald K. Evans* Ronald C. Zdellar*
Vice President and Vice President, Energy
Deputy General Counsel, Delivery Distribution Services,
Ameren Services AmerenUE
BoarD oF DIreCtors Dr. Gayle P. W. Jackson 5, 6 Gary L. Rainwater 1 Member of Finance Committee
President, Energy Global, Inc. Chairman, President 2 Member of Audit and Risk Committee
Stephen F. Brauer 1, 2
and Chief Executive Officer, 3 Member of Human Resources
James C. Johnson 3, 4
Chairman and Chief
Ameren Corporation Committee
Vice President and
Executive Officer, Hunter
4 Member of Nominating and Corporate
Assistant General Counsel, Harvey Saligman 3, 4
Engineering Company Governance Committee
Commercial Airplanes, Partner, Cynwyd Investments
Susan S. Elliott 2, 6
5 Member of Public Policy Committee
The Boeing Company Patrick T. Stokes 3, 4, 7
Chairman and Chief Executive 6 Member of Nuclear Oversight
Charles W. Mueller 1, 5, 6
Officer, Systems Service Committee
Retired Chairman and Anheuser-Busch
Enterprises, Inc. 7 Lead Director
Chief Executive Officer, Companies, Inc.
Walter J. Galvin 1, 3
Ameren Corporation Jack D. Woodard 5, 6
Senior Executive Vice
Retired Executive Vice
Douglas R. Oberhelman 2, 4
President and Chief
Group President, Caterpillar Inc. President and Chief Nuclear
Officer, Southern Nuclear
Emerson Electric Co.
Operating Company, Inc.
As of March 2, 2009
* Officer of an Ameren Corporation subsidiary only
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
(X) Annual report pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934
for the fiscal year ended December 31, 2008
( ) Transition report pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934
for the transition period from to .
Exact name of registrant as specified in its charter;
Commission State of Incorporation; IRS Employer
File Number Address and Telephone Number Identification No.
1-14756 Ameren Corporation 43-1723446
1901 Chouteau Avenue
St. Louis, Missouri 63103
1-2967 Union Electric Company 43-0559760
1901 Chouteau Avenue
St. Louis, Missouri 63103
1-3672 Central Illinois Public Service Company 37-0211380
607 East Adams Street
Springfield, Illinois 62739
333-56594 Ameren Energy Generating Company 37-1395586
1901 Chouteau Avenue
St. Louis, Missouri 63103
2-95569 CILCORP Inc. 37-1169387
300 Liberty Street
Peoria, Illinois 61602
1-2732 Central Illinois Light Company 37-0211050
300 Liberty Street
Peoria, Illinois 61602
1-3004 Illinois Power Company 37-0344645
370 South Main Street
Decatur, Illinois 62523
Securities Registered Pursuant to Section 12(b) of the Securities Exchange Act of 1934:
The following securities are registered pursuant to Section 12(b) of the Securities Exchange Act of 1934 and are listed on
the New York Stock Exchange:
Registrant Title of each class
Ameren Corporation Common Stock, $0.01 par value per share
Securities Registered Pursuant to Section 12(g) of the Securities Exchange Act of 1934:
Registrant Title of each class
Union Electric Company Preferred Stock, cumulative, no par value,
stated value $100 per share –
$4.56 Series $4.50 Series
$4.00 Series $3.50 Series
Central Illinois Public Service Company Preferred Stock, cumulative, $100 par value per share –
6.625% Series 4.90% Series
5.16% Series 4.25% Series
4.92% Series 4.00% Series
Depository Shares, each representing one-fourth of a
share of 6.625% Preferred Stock, cumulative,
$100 par value per share
Central Illinois Light Company Preferred Stock, cumulative, $100 par value per share –
Ameren Energy Generating Company, CILCORP Inc., and Illinois Power Company do not have securities registered under
either Section 12(b) or 12(g) of the Securities Exchange Act of 1934.
Indicate by check mark if each registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act of
Ameren Corporation Yes (X) No ()
Union Electric Company Yes (X) No ()
Central Illinois Public Service Company Yes () No (X)
Ameren Energy Generating Company Yes () No (X)
CILCORP Inc. Yes () No (X)
Central Illinois Light Company Yes () No (X)
Illinois Power Company Yes () No (X)
Indicate by check mark if each registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the
Securities Exchange Act of 1934.
Ameren Corporation No (X)
Yes ( )
Union Electric Company No (X)
Yes ( )
Central Illinois Public Service Company No (X)
Yes ( )
Ameren Energy Generating Company No (X)
Yes ( )
CILCORP Inc. (X) No
Central Illinois Light Company No (X)
Illinois Power Company No (X)
Indicate by check mark whether the registrants: (1) have filed all reports required to be filed by Section 13 or 15(d) of the
Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required
to file such reports), and (2) have been subject to such filing requirements for the past 90 days.
Ameren Corporation Yes (X) No ( )
Union Electric Company Yes (X) No ( )
Central Illinois Public Service Company Yes (X) No ( )
Ameren Energy Generating Company Yes (X) No ( )
Central Illinois Light Company Yes (X) No ( )
Illinois Power Company Yes (X) No ( )
CILCORP has voluntarily filed all reports that it would have been required to file if it had been subject to the requirements
of Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months.
Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein,
and will not be contained, to the best of each registrant’s knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.
Ameren Corporation ()
Union Electric Company (X)
Central Illinois Public Service Company (X)
Ameren Energy Generating Company (X)
CILCORP Inc. (X)
Central Illinois Light Company (X)
Illinois Power Company (X)
Indicate by check mark whether each registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a
smaller reporting company. See definitions of “large accelerated filer”, “accelerated filer”, and “smaller reporting company” in
Rule 12b-2 of the Securities Exchange Act of 1934.
Accelerated Accelerated Non-accelerated Reporting
Filer Filer Filer Company
Ameren Corporation (X) () () ()
Union Electric Company () () (X) ()
Central Illinois Public Service Company () () (X) ()
Ameren Energy Generating Company () () (X) ()
CILCORP Inc. () () (X) ()
Central Illinois Light Company () () (X) ()
Illinois Power Company () () (X) ()
Indicate by check mark whether each registrant is a shell company (as defined in Rule 12b-2 of the Securities Exchange
Act of 1934).
Ameren Corporation Yes ( ) No (X)
Union Electric Company Yes ( ) No (X)
Central Illinois Public Service Company Yes ( ) No (X)
Ameren Energy Generating Company Yes ( ) No (X)
CILCORP Inc. Yes ( ) No (X)
Central Illinois Light Company Yes ( ) No (X)
Illinois Power Company Yes ( ) No (X)
As of June 30, 2008, Ameren Corporation had 210,050,075 shares of its $0.01 par value common stock outstanding. The
aggregate market value of these shares of common stock (based upon the closing price of these shares on the New York
Stock Exchange on that date) held by nonaffiliates was $8,870,414,667. The shares of common stock of the other registrants
were held by affiliates as of June 30, 2008.
The number of shares outstanding of each registrant’s classes of common stock as of January 30, 2009, was as follows:
Ameren Corporation Common stock, $0.01 par value per share: 212,519,772
Union Electric Company Common stock, $5 par value per share, held by Ameren
Corporation (parent company of the registrant): 102,123,834
Central Illinois Public Service Company Common stock, no par value, held by Ameren
Corporation (parent company of the registrant): 25,452,373
Ameren Energy Generating Company Common stock, no par value, held by Ameren Energy
Resources Company, LLC (parent company of the
registrant and subsidiary of Ameren
CILCORP Inc. Common stock, no par value, held by Ameren
Corporation (parent company of the registrant): 1,000
Central Illinois Light Company Common stock, no par value, held by CILCORP Inc.
(parent company of the registrant and subsidiary of
Ameren Corporation): 13,563,871
Illinois Power Company Common stock, no par value, held by Ameren
Corporation (parent company of the registrant): 23,000,000
DOCUMENTS INCORPORATED BY REFERENCE
Portions of the definitive proxy statement of Ameren Corporation and portions of the definitive information statements of
Union Electric Company, Central Illinois Public Service Company, and Central Illinois Light Company for the 2009 annual
meetings of shareholders are incorporated by reference into Part III of this Form 10-K.
OMISSION OF CERTAIN INFORMATION
Ameren Energy Generating Company and CILCORP Inc. meet the conditions set forth in General Instruction I(1)(a) and
(b) of Form 10-K and are therefore filing this form with the reduced disclosure format allowed under that General Instruction.
This combined Form 10-K is separately filed by Ameren Corporation, Union Electric Company, Central Illinois Public
Service Company, Ameren Energy Generating Company, CILCORP Inc., Central Illinois Light Company, and Illinois Power
Company. Each registrant hereto is filing on its own behalf all of the information contained in this annual report that relates to
such registrant. Each registrant hereto is not filing any information that does not relate to such registrant, and therefore makes
no representation as to any such information.
GLOSSARY OF TERMS AND ABBREVIATIONS
We use the words “our,” “we” or “us” with respect to certain information that relates to all Ameren Companies, as defined
below. When appropriate, subsidiaries of Ameren are named specifically as we discuss their various business activities.
AERG – AmerenEnergy Resources Generating Company, a COLA – Combined construction and operating license
CILCO subsidiary that operates a non-rate-regulated electric application.
generation business in Illinois. Cooling degree-days – The summation of positive
AFS – Ameren Energy Fuels and Services Company, a differences between the mean daily temperature and a
Resources Company subsidiary that procures fuel and 65-degree Fahrenheit base. This statistic is useful for
natural gas and manages the related risks for the Ameren estimating electricity demand by residential and commercial
Companies. customers for summer cooling.
AITC – Ameren Illinois Transmission Company, a wholly CT – Combustion turbine electric generation equipment
owned subsidiary of Ameren Corporation that is engaged in used primarily for peaking capacity.
the construction and operation of transmission assets in Development Company – Ameren Energy Development
Illinois and is regulated by the ICC. Company, which was an Ameren Energy Resources
Ameren – Ameren Corporation and its subsidiaries on a Company subsidiary and parent of Genco, Marketing
consolidated basis. In references to financing activities, Company, AFS, and Medina Valley. It was eliminated in an
acquisition activities, or liquidity arrangements, Ameren is internal reorganization in February 2008.
defined as Ameren Corporation, the parent. DOE – Department of Energy, a U.S. government agency.
Ameren Companies – The individual registrants within the DRPlus – Ameren Corporation’s dividend reinvestment and
Ameren consolidated group. direct stock purchase plan.
Ameren Illinois Utilities – CIPS, IP and the rate-regulated Dth (dekatherm) – one million Btus of natural gas.
electric and gas utility operations of CILCO. EEI – Electric Energy, Inc., an 80%-owned Ameren
Ameren Services – Ameren Services Company, an Ameren Corporation subsidiary that operates non-rate-regulated
Corporation subsidiary that provides support services to electric generation facilities and FERC-regulated
Ameren and its subsidiaries. transmission facilities in Illinois. Prior to February 29, 2008,
AMIL – The balancing authority area operated by Ameren, EEI was 40% owned by UE and 40% owned by
which includes the load of the Ameren Illinois Utilities and Development Company. On February 29, 2008, UE’s 40%
the generating assets of AERG and Genco. ownership interest and Development Company’s 40%
AMMO – The balancing authority area operated by Ameren, ownership interest were transferred to Resources
which includes the load and generating assets of UE. Company. The remaining 20% is owned by Kentucky
AMT – Alternative minimum tax. Utilities Company.
ARB – Accounting Research Bulletin. EITF – Emerging Issues Task Force, an organization
ARO – Asset retirement obligations. designed to assist the FASB in improving financial reporting
Baseload – The minimum amount of electric power through the identification, discussion and resolution of
delivered or required over a given period of time at a financial issues in keeping with existing authoritative
steady rate. literature.
Btu – British thermal unit, a standard unit for measuring the ELPC – Environmental Law and Policy Center.
quantity of heat energy required to raise the temperature of EPA – Environmental Protection Agency, a U.S.
one pound of water by one degree Fahrenheit. government agency.
Capacity factor – A percentage measure that indicates how Equivalent availability factor – A measure that indicates
much of an electric power generating unit’s capacity was the percentage of time an electric power generating unit
used during a specific period. was available for service during a period.
CILCO – Central Illinois Light Company, a CILCORP ERISA – Employee Retirement Income Security Act of
subsidiary that operates a rate-regulated electric 1974, as amended.
transmission and distribution business, a non-rate- Exchange Act – Securities Exchange Act of 1934, as
regulated electric generation business through AERG, and a amended.
rate-regulated natural gas transmission and distribution FAC – A fuel and purchased power cost recovery
business, all in Illinois, as AmerenCILCO. CILCO owns all of mechanism that allows UE to recover through customer
the common stock of AERG. rates 95% of changes in fuel (coal, coal transportation,
CILCORP – CILCORP Inc., an Ameren Corporation natural gas for generation and nuclear) and purchased
subsidiary that operates as a holding company for CILCO power costs, net of off-system revenues, including MISO
and a non-rate-regulated subsidiary. costs and revenues, above or below the amount set in base
CIPS – Central Illinois Public Service Company, an Ameren rates.
Corporation subsidiary that operates a rate-regulated FASB – Financial Accounting Standards Board, a
electric and natural gas transmission and distribution rulemaking organization that establishes financial
business in Illinois as AmerenCIPS. accounting and reporting standards in the United States.
CIPSCO – CIPSCO Inc., the former parent of CIPS. FERC – The Federal Energy Regulatory Commission, a U.S.
CO2 – Carbon dioxide. government agency.
FIN – FASB Interpretation. A FIN statement is an IP SPT – Illinois Power Special Purpose Trust, which was
explanation intended to clarify accounting pronouncements created as a subsidiary of IP LLC to issue TFNs as allowed
previously issued by the FASB. under the Illinois Customer Choice Law. It was dissolved in
Fitch – Fitch Ratings, a credit rating agency. February 2009 because the remaining TFNs were redeemed
FSP – FASB Staff Position, a publication that provides by IP in September 2008.
application guidance on FASB literature. IPA – Illinois Power Agency, a state government agency
FTRs – Financial transmission rights, financial instruments that has broad authority to assist in the procurement of
that entitle the holder to pay or receive compensation for electric power for residential and nonresidential customers
certain congestion-related transmission charges between beginning in June 2009.
two designated points. ISRS – Infrastructure system replacement surcharge. A
Fuelco – Fuelco LLC, a limited-liability company that cost recovery mechanism in Missouri that allows UE to
provides nuclear fuel management and services to its recover gas infrastructure replacement costs from utility
members. The members are UE, Luminant, and Pacific Gas customers without a traditional rate case.
and Electric Company. IUOE – International Union of Operating Engineers, a labor
GAAP – Generally accepted accounting principles in the union.
United States of America. JDA – The joint dispatch agreement among UE, CIPS, and
Genco – Ameren Energy Generating Company, a Resources Genco under which UE and Genco jointly dispatched electric
Company subsidiary that operates a non-rate-regulated generation prior to its termination on December 31, 2006.
electric generation business in Illinois and Missouri. Kilowatthour – A measure of electricity consumption
Gigawatthour – One thousand megawatthours. equivalent to the use of 1,000 watts of power over a period
Heating degree-days – The summation of negative of one hour.
differences between the mean daily temperature and a 65- Lehman – Lehman Brothers Holdings, Inc.
degree Fahrenheit base. This statistic is useful as an MACT – Maximum Achievable Control Technology.
indicator of demand for electricity and natural gas for winter Marketing Company – Ameren Energy Marketing Company,
space heating for residential and commercial customers. a Resources Company subsidiary that markets power for
IBEW – International Brotherhood of Electrical Workers, a Genco, AERG and EEI.
labor union. Medina Valley – AmerenEnergy Medina Valley Cogen
ICC – Illinois Commerce Commission, a state agency that L.L.C., a Resources Company subsidiary, which owns a
regulates Illinois utility businesses, including the rate- 40-megawatt gas-fired electric generation plant.
regulated operations of CIPS, CILCO and IP. Megawatthour – One thousand kilowatthours.
Illinois Customer Choice Law – Illinois Electric Service MGP – Manufactured gas plant.
Customer Choice and Rate Relief Law of 1997, which MISO – Midwest Independent Transmission System
provided for electric utility restructuring and was designed Operator, Inc.
to introduce competition into the retail supply of electric MISO Day Two Energy Market – A market that uses
energy in Illinois. market-based pricing, incorporating transmission
Illinois electric settlement agreement – A comprehensive congestion and line losses, to compensate market
settlement of issues in Illinois arising out of the end of ten participants for power.
years of frozen electric rates, effective January 2, 2007. The Missouri Environmental Authority – Environmental
Illinois electric settlement agreement, which became Improvement and Energy Resources Authority of the state
effective on August 28, 2007, was designed to avoid new of Missouri, a governmental body authorized to finance
rate rollback and freeze legislation and legislation that would environmental projects by issuing tax-exempt bonds and
impose a tax on electric generation in Illinois. The notes.
settlement addresses the issue of power procurement, and Missouri Regulated – A financial reporting segment
it includes a comprehensive rate relief and customer consisting of UE’s rate-regulated businesses.
assistance program. Money pool – Borrowing agreements among Ameren and
Illinois EPA – Illinois Environmental Protection Agency, a its subsidiaries to coordinate and provide for certain short-
state government agency. term cash and working capital requirements. Separate
Illinois Regulated – A financial reporting segment money pools maintained for rate-regulated and non-rate-
consisting of the regulated electric and natural gas regulated business are referred to as the utility money pool
transmission and distribution businesses of CIPS, CILCO, and the non-state-regulated subsidiary money pool,
IP and AITC. respectively.
IP – Illinois Power Company, an Ameren Corporation Moody’s – Moody’s Investors Service Inc., a credit rating
subsidiary. IP operates a rate-regulated electric and natural agency.
gas transmission and distribution business in Illinois as MoPSC – Missouri Public Service Commission, a state
AmerenIP. agency that regulates Missouri utility businesses, including
IP LLC – Illinois Power Securitization Limited Liability the rate-regulated operations of UE.
Company, which was a special-purpose Delaware limited- MPS – Multi-Pollutant Standard, an agreement reached in
liability company. It was dissolved in February 2009 because 2006 among Genco, CILCO (AERG), EEI and the Illinois
the remaining TFNs, with respect to which this entity was EPA, which was codified in Illinois environmental
created, were redeemed by IP in September 2008. regulations.
MW – Megawatt. IP were remitted to IP SPT. The designated funds were
Native load – Wholesale customers and end-use retail restricted for the sole purpose of making payments of
customers, whom we are obligated to serve by statute, principal and interest on, and paying other fees and
franchise, contract, or other regulatory requirement. expenses related to, the TFNs. Since the application of FIN
NCF&O – National Congress of Firemen and Oilers, a labor 46R, IP did not consolidate IP SPT. Therefore, the
union. obligation to IP SPT appears on IP’s balance sheet as of
Non-rate-regulated Generation – A financial reporting December 31, 2007. In September 2008, IP redeemed the
segment consisting of the operations or activities of Genco, remaining TFNs.
the CILCORP parent company, AERG, EEI, Medina Valley, TVA – Tennessee Valley Authority, a public power
and Marketing Company. authority.
NOx – Nitrogen oxide. UE – Union Electric Company, an Ameren Corporation
Noranda – Noranda Aluminum, Inc. subsidiary that operates a rate-regulated electric generation,
NRC – Nuclear Regulatory Commission, a U.S. government transmission and distribution business, and a rate-regulated
agency. natural gas transmission and distribution business in
NYMEX – New York Mercantile Exchange. Missouri as AmerenUE.
NYSE – New York Stock Exchange, Inc.
OATT – Open Access Transmission Tariff.
OCI – Other comprehensive income (loss) as defined by
GAAP. Statements in this report not based on historical facts
Off-system revenues – Revenues from other than native are considered “forward-looking” and, accordingly, involve
load sales. risks and uncertainties that could cause actual results to
OTC – Over-the-counter. differ materially from those discussed. Although such
PGA – Purchased Gas Adjustment tariffs, which allow the forward-looking statements have been made in good faith
passing through of the actual cost of natural gas to utility and are based on reasonable assumptions, there is no
customers. assurance that the expected results will be achieved. These
PJM – PJM Interconnection LLC. statements include (without limitation) statements as to
PUHCA 2005 – The Public Utility Holding Company Act of future expectations, beliefs, plans, strategies, objectives,
2005, enacted as part of the Energy Policy Act of 2005, events, conditions, and financial performance. In
effective February 8, 2006. connection with the “safe harbor” provisions of the Private
Regulatory lag – Adjustments to retail electric and natural Securities Litigation Reform Act of 1995, we are providing
gas rates are based on historic cost levels. Rate increase this cautionary statement to identify important factors that
requests can take up to 11 months to be acted upon by the could cause actual results to differ materially from those
MoPSC and the ICC. As a result, revenue increases anticipated. The following factors, in addition to those
authorized by regulators will lag behind changing costs. discussed under Risk Factors and elsewhere in this report
Resources Company – Ameren Energy Resources Company, and in our other filings with the SEC, could cause actual
LLC, an Ameren Corporation subsidiary that consists of results to differ materially from management expectations
non-rate-regulated operations, including Genco, Marketing suggested in such forward-looking statements:
Company, EEI, AFS, and Medina Valley. It is the successor to
‰ regulatory or legislative actions, including changes in
Ameren Energy Resources Company, which was eliminated
regulatory policies and ratemaking determinations and
in an internal reorganization in February 2008.
future rate proceedings or future legislative actions that
RFP – Request for proposal.
seek to limit or reverse rate increases;
RTO – Regional Transmission Organization.
‰ uncertainty as to the continued effectiveness of the
S&P – Standard & Poor’s Ratings Services, a credit rating
Illinois power procurement process;
agency that is a division of The McGraw-Hill Companies,
‰ changes in laws and other governmental actions,
including monetary and fiscal policies;
SEC – Securities and Exchange Commission, a U.S.
‰ changes in laws or regulations that adversely affect the
ability of electric distribution companies and other
SERC – SERC Reliability Corporation, one of the regional
purchasers of wholesale electricity to pay their
electric reliability councils organized for coordinating the
suppliers, including UE and Marketing Company;
planning and operation of the nation’s bulk power supply.
‰ enactment of legislation taxing electric generators, in
SFAS – Statement of Financial Accounting Standards, the
Illinois or elsewhere;
accounting and financial reporting rules issued by the
‰ the effects of increased competition in the future due
to, among other things, deregulation of certain aspects
SO2 – Sulfur dioxide.
of our business at both the state and federal levels, and
TFN – Transitional Funding Trust Notes issued by IP SPT as
the implementation of deregulation, such as occurred
allowed under the Illinois Customer Choice Law. IP
when the electric rate freeze and power supply
designated a portion of cash received from customer
contracts expired in Illinois at the end of 2006;
billings to pay the TFNs. The designated funds received by