Summary of Significant Accounting Policies

Liquidity and Restructuring Activities

At June 30, 2012, Edison Mission Energy (EME), and its subsidiaries without contractual dividend restrictions, had corporate cash and cash equivalents of $879 million, which includes Midwest Generation, LLC's (Midwest Generation) cash and cash equivalents of $177 million. EME and Midwest Generation's previous revolving credit agreements have been terminated or expired and no longer are sources of liquidity. At June 30, 2012, EME had $3.7 billion of unsecured notes outstanding, $500 million of which mature in June 2013.

EME is currently experiencing operating losses due to lower realized energy and capacity prices, higher fuel costs and lower generation at the Midwest Generation plants. Forward market prices indicate that these trends are expected to continue for a number of years. As a result, EME expects that it will incur further reductions in cash flow and losses in the current year and in subsequent years. A continuation of these adverse trends coupled with pending debt maturities and the need to retrofit its Midwest Generation plants to comply with governmental regulations will exhaust EME's liquidity. Consequently, EME will need to consider all options available to it, including potential sales of assets, restructuring, reorganization of its capital structure, or conservation of cash that would be otherwise applied to the payment of obligations. EME has entered into non-disclosure and engagement agreements with advisors representing certain of its unsecured bondholders for the purpose of engaging in discussions with such advisors and Edison International regarding EME's financial condition. Absent a restructuring of its obligations, based on current projections, EME is not expected to have sufficient liquidity to repay the $500 million debt obligation due in June 2013. As a result, EME may need to file for protection under Chapter 11 of the U.S. Bankruptcy Code.

Bankruptcy proceedings could lead to a change of control of EME , which would result in the termination of EME's tax-allocation agreement. At June 30, 2012, EME had recognized $323 million of net deferred tax benefits based on continued ownership by Edison International and inclusion of EME in the consolidated income tax returns of Edison International and its subsidiaries. If it is more likely than not that EME would no longer continue to participate as part of the consolidated group of Edison International, EME would record a valuation allowance to reduce the carrying value of its net deferred tax benefit and record a material charge against earnings. The termination of the tax-allocation agreement could adversely affect EME's long-term liquidity because realization of the value of tax benefits generated by EME could be deferred until such time that EME, or a subsequent owner of EME, had the ability to utilize such benefits. There is no assurance as to when, or whether, this might occur.

The accompanying consolidated financial statements have been prepared assuming that EME will continue as a going concern. Financial statements prepared on this basis assume the realization of assets and the satisfaction of liabilities in the normal course of business for the 12-month period following the date of these financial statements. There is no assurance that EME will be able to continue as a going concern.

Basis of Presentation

EME's significant accounting policies were described in "Note 1. Summary of Significant Accounting Policies" on page 68 of EME's annual report on Form 10-K for the year ended December 31, 2011. EME follows the same accounting policies for interim reporting purposes, with the exception of accounting principles adopted as of January 1, 2012, as discussed below in "—New Accounting Guidance." This quarterly report should be read in conjunction with such financial statements and notes.

In the opinion of management, all adjustments, consisting of recurring accruals, have been made that are necessary to fairly state the consolidated financial position and results of operations and cash flows in accordance with accounting principles generally accepted in the United States of America (GAAP) for the periods covered by this quarterly report on Form 10-Q. The results of operations for the three- and six-month periods ended June 30, 2012 are not necessarily indicative of the operating results for the full year. Except as indicated, amounts reflected in the notes to the consolidated financial statements relate to continuing operations of EME.

The December 31, 2011 condensed consolidated balance sheet data was derived from audited financial statements, but does not include all disclosures required by GAAP.

The consolidated statement of cash flows for the six months ended June 30, 2011 was revised to correct an error in the presentation of vendor financed property, plant and equipment in the amount of $19 million. This correction, to present the amount on a net rather than gross basis, decreased cash flows used in investing activities and cash flows provided by financing activities by this amount, but had no impact on the net change in cash and cash equivalents. Management believes the revision does not have a material impact on the prior year financial statements.

Cash Equivalents

Cash equivalents included money market funds totaling $873 million and $1.2 billion at June 30, 2012 and December 31, 2011, respectively. The carrying value of cash equivalents equals the fair value as all investments have original maturities of less than three months.

Restricted Cash and Cash Equivalents, and Restricted Deposits

Restricted cash and cash equivalents at June 30, 2012 and December 31, 2011 included $97 million received from a wind project financing that was held in escrow at those dates. At June 30, 2012, restricted deposits included $51 million to support outstanding letters of credit issued under EME's letter of credit facilities.

Inventory

Inventory is stated at the lower of weighted-average cost or market. Inventory is recorded at actual cost when purchased and then expensed at weighted-average cost as used. Inventory consisted of the following:



(in millions)	June 30, 2012		December 31, 2011
Coal, fuel oil and other raw materials	$	142	$	188
Spare parts, materials and supplies	90		86
Total inventory	$	232	$	274

Allocation of Net Income or Losses to Investors in Certain Variable Interest Entities

Capistrano Wind Partners' partnership agreements contain complex allocation provisions for taxable income and losses, tax credits and cash distributions. EME allocates net income for this consolidated investment to third-party investors based on the Hypothetical Liquidation Book Value (HLBV) method. HLBV is a balance sheet oriented approach that calculates the change in the claims of each partner on the net assets of the investment at the beginning and end of each period. Each partner's claim is equal to the amount each party would receive or pay if the net assets of the investment were to liquidate at book value and the resulting cash was then distributed to investors in accordance with their respective liquidation preferences. EME reports the net income (loss) attributable to the third-party investors as income (loss) attributable to noncontrolling interests in the consolidated statements of operations. For further information, see Note 3—Variable Interest Entities—Projects or Entities that are Consolidated—Capistrano Wind Equity Capital.

New Accounting Guidance

Accounting Guidance Adopted in 2012

Fair Value Measurement

In May 2011, the Financial Accounting Standards Board (FASB) issued an accounting standards update modifying the fair value measurement and disclosure guidance. This guidance prohibits grouping of financial instruments for purposes of fair value measurement and requires the value be based on the individual security. This amendment also results in new disclosures primarily related to Level 3 measurements including quantitative disclosure about unobservable inputs and assumptions, a description of the valuation processes and a narrative description of the sensitivity of the fair value to changes in unobservable inputs. EME adopted this guidance effective January 1, 2012. For further information, see Note 4—Fair Value Measurements.

Presentation of Comprehensive Income

In June 2011 and December 2011, the FASB issued accounting standards updates on the presentation of comprehensive income. An entity can elect to present items of net income and other comprehensive income in one continuous statement, referred to as the statement of comprehensive income, or in two separate but consecutive statements. EME adopted this guidance January 1, 2012 and elected to present two separate but consecutive statements. The adoption of these accounting standards updates did not change the items that constitute net income and other comprehensive income.

Accounting Guidance Not Yet Adopted

Offsetting Assets and Liabilities

In December 2011, the FASB issued an accounting standards update modifying the disclosure requirements about the nature of an entity's rights of offsetting assets and liabilities in the statement of financial position under master netting agreements and related arrangements associated with financial and derivative instruments. The guidance requires increased disclosure of the gross and net recognized assets and liabilities, collateral positions and narrative descriptions of setoff rights. EME will adopt this guidance effective January 1, 2013.