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<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'><b><font style="font-size: 13.5pt">&nbsp;</font></b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'><b><font style="font-size: 13.5pt">&nbsp;</font></b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'><b><font style="font-size: 13.5pt">UNITED STATES</font></b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'><b><font style="font-size: 13.5pt">SECURITIES AND EXCHANGE COMMISSION</font></b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'><b>Washington,
D.C. 20549</b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>_______________________________</b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'><b><font style="font-size: 18.0pt">FORM 8&#8209;K</font></b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'><b>CURRENT
REPORT</b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;text-align:center'><b>Pursuant
to Section 13 or 15(d) of the<br>
Securities Exchange Act of 1934</b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b><i>__________________________________</i></b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>&nbsp;</b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'>Date of Report (Date
of earliest event reported):&nbsp; May 24, 2011</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<div align=center>

<table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0
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 <tr>
  <td width=72 valign=top style='width:.75in;padding:0in 5.4pt 0in 5.4pt'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'>&nbsp;</p>
  </td>
  <td width=504 valign=top style='width:5.25in;border:none;border-bottom:solid windowtext 1.0pt;
  padding:0in 5.4pt 0in 5.4pt'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b><font style="font-size: 14.0pt">PLUG POWER INC.</font></b></p>
  </td>
  <td width=63 valign=top style='width:47.4pt;padding:0in 5.4pt 0in 5.4pt'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'>&nbsp;</p>
  </td>
 </tr>
</table>

</div>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:.25in;text-align:center'><b><font style="font-size: 10.0pt">(Exact name of registrant as specified in charter)</font></b></p>

<div align=center>

<table class=MsoNormalTable border=0 cellpadding=0
 style='margin-left:0pt;border-collapse:collapse' width="100%">
 <tr>
  <td valign=top style='padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>Delaware</b></p>
  </td>
  <td valign=top style='padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>1-34392</b></p>
  </td>
  <td valign=top style='padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>22-3672377</b></p>
  </td>
 </tr>
 <tr>
  <td valign=top style='padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'>(State or Other <br>
  Jurisdiction<br>
  of Incorporation)</p>
  </td>
  <td valign=top style='padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'>(Commission File
  Number)</p>
  </td>
  <td valign=top style='padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'>(IRS Employer<br>
  Identification No.)</p>
  </td>
 </tr>
</table>

</div>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-top:.25in;text-align:center'><b><u>968
Albany Shaker Road, Latham, New York&nbsp; 12110<br>
</u></b><b><font style="font-size: 10.0pt">(Address of Principal Executive
Offices)&nbsp; (Zip Code)</font></b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-top:.25in;text-align:center'><b><u>(518)
782-7700<br>
</u></b><b><font style="font-size: 10.0pt">(Registrant&#146;s telephone number,
including area code)</font></b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>Check the
appropriate box below if the Form 8-K filing is intended to simultaneously
satisfy the filing obligation of the registrant under any of the following
provisions (<i>see </i>General Instruction A.2. below):</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<font face="Wingdings">o</font>&nbsp;&nbsp; Written communications
pursuant to Rule 425 under the Securities Act (17 CFR 230.425)</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<font face="Wingdings">o</font>&nbsp;&nbsp; Soliciting material
pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;<a
name=SelTemp></a></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<div style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>

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<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

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<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<font face="Wingdings">o</font>&nbsp;&nbsp; Pre-commencement
communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR
240.14d-2(b))</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<font face="Wingdings">o</font>&nbsp;&nbsp; Pre-commencement
communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR
240.13e-4(c))</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:justify;line-height:13.0pt'>&nbsp;</p>
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<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">
2</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">&nbsp;</p>

<div style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>

<hr size=2 width="100%" noshade color=navy align=center>

</b></div>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

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style='page-break-before:always'>


<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'><b>Item 1.01&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Entry into a Material Definitive
Agreement.</b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin-right:0in;margin-left:0in;font-size:12.0pt;font-family:"Times New Roman";margin:0in;margin-bottom:.0001pt;text-indent:.5in'>On May 25, 2011,
Plug Power Inc. (the &#147;Company&#148;) entered into an underwriting agreement (the
&#147;Underwriting Agreement&#148;) with Roth Capital Partners, LLC as the sole manager
(the &#147;Underwriter&#148;), related to the public offering of (i) an aggregate of 8,265,000
shares of the Company&#146;s common stock, par value $0.01 per share (&#147;Common
Stock&#148;), and (ii) warrants to purchase an aggregate of 6,198,750 shares of
Common Stock (the &#147;Warrants&#148;).&nbsp; The shares of Common Stock and Warrants
are being sold together as a fixed combination, each consisting of one share of
Common Stock and 0.75 of a Warrant to purchase one share of Common Stock, at a
public offering price of $2.42 per combination, less the underwriting discounts
and commissions payable by the Company (the &#147;Offering&#148;).&nbsp; The Underwriter
will purchase the Common Stock and Warrants at a discounted price of $2.299 per
combination, representing a five percent (5.0%) discount to the public offering
price.&nbsp; The Company has granted the Underwriter the option to purchase, at
the same discounted price, an&nbsp; aggregate of up to an additional (i) 1,239,750
shares of Common Stock and/or (ii) Warrants to purchase up to 929,813 shares of
Common Stock as may be necessary to cover over-allotments made in connection
with the Offering.&nbsp; The Common Stock and/or Warrants purchased under this
option may be sold either together or separately in any combination to be
determined by the Underwriter.&nbsp; </p>

<p style='margin-right:0in;margin-left:0in;font-size:12.0pt;font-family:"Times New Roman";margin:0in;margin-bottom:.0001pt;text-indent:.5in'>&nbsp;</p>

<p style='margin-right:0in;margin-left:0in;font-size:12.0pt;font-family:"Times New Roman";margin:0in;margin-bottom:.0001pt;text-indent:.5in'>The Warrants to be
issued in the Offering are exercisable beginning on the date of issuance and will
expire on May 31, 2016.&nbsp; The exercise price of the Warrants is $3.00 per
share of Common Stock.&nbsp; The exercise price and number of shares of Common
Stock issuable upon exercise of the Warrants will be subject to adjustment in
the event of any stock split, reverse stock split, stock dividend, recapitalization,
reorganization or similar transaction, among other events as described in the
Warrants.&nbsp; The Warrants also include weighted-average anti-dilution
protection in the event of the issuance of any common stock, securities
convertible into common stock, or certain other issuances at a price below the
then-current exercise price of the Warrants, with certain exceptions.&nbsp; In
the event of a sale of the Company, each holder of Warrants has the right,
exercisable at its option, to require the Company to purchase such holder&#146;s
Warrants at a price determined using a Black-Scholes option pricing model as
described in the Warrants.</p>

<p style='margin-right:0in;margin-left:0in;font-size:12.0pt;font-family:"Times New Roman";margin:0in;margin-bottom:.0001pt;text-indent:.5in'>&nbsp;</p>

<p style='margin-right:0in;margin-left:0in;font-size:12.0pt;font-family:"Times New Roman";margin:0in;margin-bottom:.0001pt;text-indent:.5in'>The Offering is
expected to close on May 31, 2011, subject to the satisfaction of customary
closing conditions.&nbsp; The net proceeds to the Company are expected to be
approximately $18.3 million, assuming no exercise of the Warrants and after
deducting underwriting discounts and commissions and estimated expenses payable
by the Company associated with the Offering.&nbsp; The Offering is being made
pursuant to the Company&#146;s existing shelf registration statement on Form S-3
(File No. 333-173268), which was filed with the Securities and Exchange
Commission (the &#147;Commission&#148;) on April 1, 2011 and declared effective by the
Commission on April 8, 2011 and is described in more detail in a prospectus
supplement dated May 25, 2011 and an accompanying base prospectus dated April
1, 2011. </p>

<p style='margin-right:0in;margin-left:0in;font-size:12.0pt;font-family:"Times New Roman";margin:0in;margin-bottom:.0001pt;text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">
3</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">&nbsp;</p>

<div style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>

<hr size=2 width="100%" noshade color=navy align=center>

</b></div>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

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style='page-break-before:always'>


<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>The Underwriting Agreement contains
customary representations, warranties, and agreements by the Company, and
customary conditions to closing, indemnification obligations of the Company and
the Underwriter, including for liabilities under the Securities Act of 1933, as
amended, other obligations of the parties, and termination provisions. </p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>Pursuant to the Underwriting
Agreement, the Company agreed, subject to certain exceptions, not to offer,
issue or sell any shares of Common Stock or securities convertible into or
exercisable or exchangeable for shares of Common Stock for a period of ninety
(90) days following the Offering without the prior written consent of the
Underwriter. </p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>The Underwriting Agreement has been
attached hereto as an exhibit to provide investors and security holders with
information regarding its terms.&nbsp; It is not intended to provide any other
factual information about the Company.&nbsp; The representations, warranties and
covenants contained in the Underwriting Agreement were made only for purposes
of the Underwriting Agreement and as of specific dates, were solely for the
benefit of the parties to the Underwriting Agreement, and may be subject to
limitations agreed upon by the contracting parties, including being qualified
by confidential disclosures exchanged between the parties in connection with
the execution of the Underwriting Agreement. </p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>A copy of the opinion of Goodwin
Procter LLP relating to the legality of the issuance and sale of the securities
in the Offering is attached as Exhibit 5.1 hereto.&nbsp; Copies of the Underwriting
Agreement and the form of Warrant to be issued in connection with the Offering
are filed herewith as Exhibits 1.1 and 4.1, respectively, and are incorporated
herein by reference.&nbsp; The foregoing description of the Offering by the Company
and the documentation related thereto does not purport to be complete and is
qualified in its entirety by reference to such Exhibits. </p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>On May 24, 2011, the Company issued
a press release announcing the Offering. On May 25, 2011, the Company issued a
press release announcing the pricing of the Offering. Copies of the press
releases are attached hereto as Exhibits 99.1 and 99.2, respectively, and each
is incorporated herein by reference. </p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">
4</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">&nbsp;</p>

<div style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>

<hr size=2 width="100%" noshade color=navy align=center>

</b></div>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<br clear=all
style='page-break-before:always'>


<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";page-break-after:avoid;text-autospace:none'><b>Item
9.01.&nbsp; Financial Statements and Exhibits</b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";page-break-after:avoid;text-autospace:none'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'>d)
Exhibits. <a name="OLE_LINK2"></a><a name="OLE_LINK1"></a></p>

<table class=MsoTableGrid border=0 cellpadding=0
 style='border-collapse:collapse' width="100%">
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  1px solid windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";page-break-after:avoid'>Exhibit Number</p>
  </td>
  <td width=32 valign=bottom style='border-bottom:medium none #000000; width:23.85pt;border-left-style:none; border-left-width:medium; border-right-style:none; border-right-width:medium; border-top-style:none; border-top-width:medium; padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";page-break-after:avoid'>&nbsp;</p>
  </td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  1px solid windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";page-break-after:avoid'>Description</p>
  </td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  1.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Underwriting
  Agreement dated as of May 25, 2011 by and between Plug Power Inc. and Roth
  Capital Partners, LLC.</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  4.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Form
  of Warrant</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  5.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Opinion
  of Goodwin Procter LLP</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  23.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Consent
  of Goodwin Procter LLP (contained in Exhibit 5.1)</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  99.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Press
  release of Plug Power Inc. issued May 24, 2011</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=top style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:medium none windowtext;
  padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:.25in;page-break-after:avoid'>99.2</p>
  </td>
  <td width=32 valign=top style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'><font style="font-size: 10.0pt">&nbsp;</font></p>
  </td>
  <td width=441 valign=top style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'>Press
  release of Plug Power Inc. issued May 25, 2011</p>
  </td>
 </tr>
 <tr>
  <td width=107 valign=top style='border-left:medium none; border-right:medium none; border-top:1px solid #000000; border-bottom:medium none; width:80.55pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:.25in;page-break-after:avoid'><font style="font-size: 10.0pt">&nbsp;</font></p>
  </td>
  <td width=32 valign=top style='border-top:medium none #000000; width:23.85pt;border-left-style:none; border-left-width:medium; border-right-style:none; border-right-width:medium; border-bottom-style:none; border-bottom-width:medium; padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'><font style="font-size: 10.0pt">&nbsp;</font></p>
  </td>
  <td width=441 valign=top style='border-left:medium none; border-right:medium none; border-top:1px solid #000000; border-bottom:medium none; width:331.05pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'>&nbsp;</p>
  </td>
 </tr>
</table>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-indent:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">
5</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">&nbsp;</p>

<div style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>

<hr size=2 width="100%" noshade color=navy align=center>

</b></div>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<br clear=all
style='page-break-before:always'>


<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt'><font style="font-size: 10.0pt">&nbsp;</font></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:24.0pt;text-align:center'><b>SIGNATURES</b></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:6.0pt;text-indent:.5in'>Pursuant to the
requirements of the Securities Exchange Act of 1934, the registrant has duly
caused this report to be signed on its behalf by the undersigned hereunto duly
authorized.</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:6.0pt;text-indent:.5in'><font style="font-size: 10.0pt">&nbsp;</font></p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:6.0pt;text-indent:.5in'><font style="font-size: 10.0pt">&nbsp;</font></p>

<table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width="100%"
 style='width:100.0%;border-collapse:collapse'>
 <tr>
  <td style='padding:0in 0in 0in 0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>
  </td>
  <td style='padding:0in 0in 0in 0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-left:13.65pt'>PLUG POWER INC.</p>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-left:13.65pt'>&nbsp; </p>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-left:13.65pt'>&nbsp; </p>
  </td>
 </tr>
 <tr>
  <td style='padding:0in 0in 0in 0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>Date:&nbsp; May 25, 2011</p>
  </td>
  <td style='padding:0in 0in 0in 0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-left:13.65pt'>By:
	<u>&nbsp;/s/&nbsp; Andrew Marsh&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
	</u></p>
  </td>
 </tr>
 <tr>
  <td style='padding:0in 0in 0in 0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>
  </td>
  <td style='padding:0in 0in 0in 0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-left:36.35pt'>Andrew Marsh, President and</p>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-left:36.35pt'>&nbsp;Chief Executive Officer.</p>
  </td>
 </tr>
 <tr>
  <td style='padding:0in 0in 0in 0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>
  </td>
  <td style='padding:0in 0in 0in 0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-left:13.65pt'>&nbsp;</p>
  </td>
 </tr>
</table>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-left:.5in'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">
6</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">&nbsp;</p>

<div style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";text-align:center'><b>

<hr size=2 width="100%" noshade color=navy align=center>

</b></div>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<br clear=all
style='page-break-before:always'>


<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";'>&nbsp;</p>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

<p style='margin-top:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:0in;font-size:12.0pt;font-family:"Times New Roman";text-align:center'>EXHIBIT INDEX</p>

<table class=MsoTableGrid border=0 cellpadding=0
 style='border-collapse:collapse' width="100%" id="table1">
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  1px solid windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";page-break-after:avoid'>Exhibit Number</p>
  </td>
  <td width=32 valign=bottom style='border-bottom:medium none #000000; width:23.85pt;border-left-style:none; border-left-width:medium; border-right-style:none; border-right-width:medium; border-top-style:none; border-top-width:medium; padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";page-break-after:avoid'>&nbsp;</p>
  </td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  1px solid windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";page-break-after:avoid'>Description</p>
  </td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  1.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Underwriting
  Agreement dated as of May 25, 2011 by and between Plug Power Inc. and Roth
  Capital Partners, LLC.</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  4.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Form
  of Warrant</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  5.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Opinion
  of Goodwin Procter LLP</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  23.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Consent
  of Goodwin Procter LLP (contained in Exhibit 5.1)</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  99.1</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  Press
  release of Plug Power Inc. issued May 24, 2011</td>
 </tr>
 <tr>
  <td width=107 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=32 valign=bottom style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
  <td width=441 valign=bottom style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  &nbsp;</td>
 </tr>
 <tr>
  <td width=107 valign=top style='border-left:medium none; border-right:medium none; border-top:medium none; width:80.55pt;border-bottom:medium none windowtext;
  padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:.25in;page-break-after:avoid'>99.2</p>
  </td>
  <td width=32 valign=top style='border-style:none; border-width:medium; width:23.85pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'><font style="font-size: 10.0pt">&nbsp;</font></p>
  </td>
  <td width=441 valign=top style='border-left:medium none; border-right:medium none; border-top:medium none; width:331.05pt;border-bottom:
  medium none windowtext;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'>Press
  release of Plug Power Inc. issued May 25, 2011</p>
  </td>
 </tr>
 <tr>
  <td width=107 valign=top style='border-left:medium none; border-right:medium none; border-top:1px solid #000000; border-bottom:medium none; width:80.55pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:.25in;page-break-after:avoid'><font style="font-size: 10.0pt">&nbsp;</font></p>
  </td>
  <td width=32 valign=top style='border-top:medium none #000000; width:23.85pt;border-left-style:none; border-left-width:medium; border-right-style:none; border-right-width:medium; border-bottom-style:none; border-bottom-width:medium; padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'><font style="font-size: 10.0pt">&nbsp;</font></p>
  </td>
  <td width=441 valign=top style='border-left:medium none; border-right:medium none; border-top:1px solid #000000; border-bottom:medium none; width:331.05pt;padding-left:5.4pt; padding-right:5.4pt; padding-top:0in; padding-bottom:0in'>
  <p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";margin-bottom:12.0pt;page-break-after:avoid'>&nbsp;</p>
  </td>
 </tr>
</table>

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<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">&nbsp;</p>
<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";' align="center">
7</p>

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<hr size=2 width="100%" noshade color=navy align=center>

</b></div>

<p style='margin:0in;margin-bottom:.0001pt;font-size:12.0pt;font-family:"Times New Roman";line-height:1.0pt'>&nbsp;</p>

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[{"type": "8-K", "sequence": "1", "filename": "esplugpower8k.htm", "secsgml_size_bytes": 54530}]
{"company-data": {"conformed-name": "PLUG POWER INC", "cik": "0001093691", "assigned-sic": "3620", "irs-number": "223672377", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-34392", "film-number": "11869900"}, "business-address": {"street1": "968 ALBANY-SHAKER ROAD", "city": "LATHAM", "state": "NY", "zip": "12110", "phone": "5187827700"}, "mail-address": {"street1": "968 ALBANY-SHAKER ROAD", "city": "LATHAM", "state": "NY", "zip": "12110"}}
_
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington,
D.C. 20549
_______________________________
FORM 8‑K
CURRENT
REPORT
Pursuant
to Section 13 or 15(d) of the
Securities Exchange Act of 1934
__________________________________
Date of Report (Date
of earliest event reported):  May 24, 2011
PLUG POWER INC.
(Exact name of registrant as specified in charter)
Delaware
1-34392
22-3672377
(State or Other
Jurisdiction
of Incorporation)
(Commission File
  Number)
(IRS Employer
Identification No.)
968
Albany Shaker Road, Latham, New York  12110
(Address of Principal Executive
Offices)  (Zip Code)
(518)
782-7700
(Registrant's telephone number,
including area code)
Check the
appropriate box below if the Form 8-K filing is intended to simultaneously
satisfy the filing obligation of the registrant under any of the following
provisions (
see
General Instruction A.2. below):
o
Written communications
pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
o
Soliciting material
pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
o
Pre-commencement
communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR
240.14d-2(b))
o
Pre-commencement
communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR
240.13e-4(c))
2
Item 1.01        Entry into a Material Definitive
Agreement.
On May 25, 2011,
Plug Power Inc. (the "Company") entered into an underwriting agreement (the
"Underwriting Agreement") with Roth Capital Partners, LLC as the sole manager
(the "Underwriter"), related to the public offering of (i) an aggregate of 8,265,000
shares of the Company's common stock, par value $0.01 per share ("Common
Stock"), and (ii) warrants to purchase an aggregate of 6,198,750 shares of
Common Stock (the "Warrants").  The shares of Common Stock and Warrants
are being sold together as a fixed combination, each consisting of one share of
Common Stock and 0.75 of a Warrant to purchase one share of Common Stock, at a
public offering price of $2.42 per combination, less the underwriting discounts
and commissions payable by the Company (the "Offering").  The Underwriter
will purchase the Common Stock and Warrants at a discounted price of $2.299 per
combination, representing a five percent (5.0%) discount to the public offering
price.  The Company has granted the Underwriter the option to purchase, at
the same discounted price, an  aggregate of up to an additional (i) 1,239,750
shares of Common Stock and/or (ii) Warrants to purchase up to 929,813 shares of
Common Stock as may be necessary to cover over-allotments made in connection
with the Offering.  The Common Stock and/or Warrants purchased under this
option may be sold either together or separately in any combination to be
determined by the Underwriter.
The Warrants to be
issued in the Offering are exercisable beginning on the date of issuance and will
expire on May 31, 2016.  The exercise price of the Warrants is $3.00 per
share of Common Stock.  The exercise price and number of shares of Common
Stock issuable upon exercise of the Warrants will be subject to adjustment in
the event of any stock split, reverse stock split, stock dividend, recapitalization,
reorganization or similar transaction, among other events as described in the
Warrants.  The Warrants also include weighted-average anti-dilution
protection in the event of the issuance of any common stock, securities
convertible into common stock, or certain other issuances at a price below the
then-current exercise price of the Warrants, with certain exceptions.  In
the event of a sale of the Company, each holder of Warrants has the right,
exercisable at its option, to require the Company to purchase such holder's
Warrants at a price determined using a Black-Scholes option pricing model as
described in the Warrants.
The Offering is
expected to close on May 31, 2011, subject to the satisfaction of customary
closing conditions.  The net proceeds to the Company are expected to be
approximately $18.3 million, assuming no exercise of the Warrants and after
deducting underwriting discounts and commissions and estimated expenses payable
by the Company associated with the Offering.  The Offering is being made
pursuant to the Company's existing shelf registration statement on Form S-3
(File No. 333-173268), which was filed with the Securities and Exchange
Commission (the "Commission") on April 1, 2011 and declared effective by the
Commission on April 8, 2011 and is described in more detail in a prospectus
supplement dated May 25, 2011 and an accompanying base prospectus dated April
1, 2011.
3
The Underwriting Agreement contains
customary representations, warranties, and agreements by the Company, and
customary conditions to closing, indemnification obligations of the Company and
the Underwriter, including for liabilities under the Securities Act of 1933, as
amended, other obligations of the parties, and termination provisions.
Pursuant to the Underwriting
Agreement, the Company agreed, subject to certain exceptions, not to offer,
issue or sell any shares of Common Stock or securities convertible into or
exercisable or exchangeable for shares of Common Stock for a period of ninety
(90) days following the Offering without the prior written consent of the
Underwriter.
The Underwriting Agreement has been
attached hereto as an exhibit to provide investors and security holders with
information regarding its terms.  It is not intended to provide any other
factual information about the Company.  The representations, warranties and
covenants contained in the Underwriting Agreement were made only for purposes
of the Underwriting Agreement and as of specific dates, were solely for the
benefit of the parties to the Underwriting Agreement, and may be subject to
limitations agreed upon by the contracting parties, including being qualified
by confidential disclosures exchanged between the parties in connection with
the execution of the Underwriting Agreement.
A copy of the opinion of Goodwin
Procter LLP relating to the legality of the issuance and sale of the securities
in the Offering is attached as Exhibit 5.1 hereto.  Copies of the Underwriting
Agreement and the form of Warrant to be issued in connection with the Offering
are filed herewith as Exhibits 1.1 and 4.1, respectively, and are incorporated
herein by reference.  The foregoing description of the Offering by the Company
and the documentation related thereto does not purport to be complete and is
qualified in its entirety by reference to such Exhibits.
On May 24, 2011, the Company issued
a press release announcing the Offering. On May 25, 2011, the Company issued a
press release announcing the pricing of the Offering. Copies of the press
releases are attached hereto as Exhibits 99.1 and 99.2, respectively, and each
is incorporated herein by reference.
4
Item
9.01.  Financial Statements and Exhibits
d)
Exhibits.
Exhibit Number
Description
1.1
Underwriting
  Agreement dated as of May 25, 2011 by and between Plug Power Inc. and Roth
  Capital Partners, LLC.
4.1
Form
  of Warrant
5.1
Opinion
  of Goodwin Procter LLP
23.1
Consent
  of Goodwin Procter LLP (contained in Exhibit 5.1)
99.1
Press
  release of Plug Power Inc. issued May 24, 2011
99.2
Press
  release of Plug Power Inc. issued May 25, 2011
5
SIGNATURES
Pursuant to the
requirements of the Securities Exchange Act of 1934, the registrant has duly
caused this report to be signed on its behalf by the undersigned hereunto duly
authorized.
PLUG POWER INC.
Date:  May 25, 2011
By:
/s/  Andrew Marsh
Andrew Marsh, President and
Chief Executive Officer.
6
EXHIBIT INDEX
Exhibit Number
Description
1.1
Underwriting
  Agreement dated as of May 25, 2011 by and between Plug Power Inc. and Roth
  Capital Partners, LLC.
4.1
Form
  of Warrant
5.1
Opinion
  of Goodwin Procter LLP
23.1
Consent
  of Goodwin Procter LLP (contained in Exhibit 5.1)
99.1
Press
  release of Plug Power Inc. issued May 24, 2011
99.2
Press
  release of Plug Power Inc. issued May 25, 2011
7