<SUBMISSION>
<ACCESSION-NUMBER>0001140361-12-026080
<TYPE>4
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<PERIOD>20120515
<FILING-DATE>20120517
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<CONFORMED-NAME>OBERNDORF WILLIAM E
<CIK>0001218663
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<ACT>34
<FILE-NUMBER>001-12079
<FILM-NUMBER>12852485
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<MAIL-ADDRESS>
<STREET1>SPO PARTNERS & CO
<STREET2>591 REDWOOD HWY STE 3215
<CITY>MILL VALLEY
<STATE>CA
<ZIP>94941
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<ISSUER>
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<CONFORMED-NAME>CALPINE CORP
<CIK>0000916457
<ASSIGNED-SIC>4911
<IRS-NUMBER>770212977
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
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<STREET1>717 TEXAS AVENUE
<STREET2>SUITE 1000
<CITY>HOUSTON
<STATE>TX
<ZIP>77002
<PHONE>7138302000
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<STREET1>717 TEXAS AVENUE
<STREET2>SUITE 1000
<CITY>HOUSTON
<STATE>TX
<ZIP>77002
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<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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    <periodOfReport>2012-05-15</periodOfReport>

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        <issuerName>CALPINE CORP</issuerName>
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            <rptOwnerName>OBERNDORF WILLIAM E</rptOwnerName>
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                <value>Common Stock, par value $0.001 per share</value>
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    <footnotes>
        <footnote id="F1">Represents award of restricted stock units pursuant to Calpine Corporation's Amended and Restated 2008 Director Incentive Plan. The award vests on the earlier to occur of (i) the first anniversary of the grant date or (ii) the day immediately preceding the date of the 2013 annual meeting of stockholders. The vested shares will be issued and delivered to the reporting person on the earliest to occur of (i) the reporting person's elected distribution date, (ii) a change of control of the Company, or (iii) the reporting person's termination of service on the board of directors.  Each restricted stock unit represents a contingent right to receive one share of Calpine Corporation common stock.  The restricted stock units are settled solely in common stock.</footnote>
        <footnote id="F2">Includes 28,700 shares of Calpine Corporation common stock held in the William E. Oberndorf individual retirement account that is self directed.</footnote>
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    <remarks>Exhibit 24.1 - Power of Attorney</remarks>

    <ownerSignature>
        <signatureName>/s/ W. Thaddeus Miller, as Attorney-in-Fact</signatureName>
        <signatureDate>2012-05-17</signatureDate>
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<TYPE>EX-24.1
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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; TEXT-DECORATION: underline">POWER OF ATTORNEY</font></font></div>

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<div style="TEXT-INDENT: 36pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-WEIGHT: bold">KNOW ALL MEN BY THESE PRESENTS</font>, that the undersigned hereby constitutes and appoints <font style="DISPLAY: inline; FONT-WEIGHT: bold">W. Thaddeus Miller and Jim D. Deidiker, </font>and each of them<font style="DISPLAY: inline; FONT-WEIGHT: bold">,</font> his true and lawful attorneys-in-fact to:</font></div>

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<div style="TEXT-INDENT: 36pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">(1)&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;execute for and on behalf of the undersigned, in the undersigned&#8217;s capacity as an officer and/or director of Calpine Corporation (the &#8220;Company&#8221;), any and all Forms 3, 4 or 5 required to be filed by the undersigned in accordance with Section 16(a) of the Securities Exchange Act of 1934, as amended (the &#8220;1934 Act&#8221;), and the rules thereunder;</font></div>

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<div style="TEXT-INDENT: 36pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">(2)&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;do and perform any and all acts for and on behalf of the undersigned which may be necessary or desirable to complete and execute any such Forms 3, 4 or 5 and timely file each form with the United States Securities and Exchange Commission and any stock exchange or similar authority; and</font></div>

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<div style="TEXT-INDENT: 36pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">(3)&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;take any other action of any type whatsoever in connection with the foregoing which, in the opinion of either such attorney-in-fact, may be of benefit to, in the best interest of, or legally required by, the undersigned, it being understood that the documents executed by either such attorney-in-fact on behalf of the undersigned, pursuant to this attorney-in-fact may approve in his discretion.</font></div>

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<div style="TEXT-INDENT: 36pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">The undersigned hereby grants to such attorney-in-fact, and any one of them, full power and authority to do and perform all and every act and thing whatsoever requisite, necessary, and proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that such attorney-in-fact, or his substitute or substitutes, shall lawfully do or cause to be done by virtue of the Power of Attorney and the rights and powers herein granted.&#160;&#160;The undersigned acknowledges that none of such attorneys-in-fact, in serving in such capacity at the request of the undersigned, is hereby assuming, nor is the Company hereby assuming, any of the undersigned&#8217;s responsibilities to comply with Section&#160;16 of the 1934 Act.</font></div>

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<div style="TEXT-INDENT: 36pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file Forms 3, 4 or 5 with respect to the undersigned&#8217;s holdings of and transactions in securities issued by the Company, unless earlier revoked by the undersigned in a signed writing delivered to the foregoing attorney-in-fact.</font></div>

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<div style="TEXT-INDENT: 36pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-WEIGHT: bold">IN WITNESS WHEREOF</font>, the undersigned has caused this Power of Attorney to be executed as of this 16<font style="DISPLAY: inline; FONT-SIZE: 70%; VERTICAL-ALIGN: text-top">th</font> day of May 2012.</font></div>

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<td width="38%"><font style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160;<font style="DISPLAY: inline; FONT-WEIGHT: bold">William E. Oberndorf</font></font></td>
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