<SUBMISSION>
<ACCESSION-NUMBER>0001193125-08-218861
<TYPE>FWP
<PUBLIC-DOCUMENT-COUNT>1
<FILING-DATE>20081029
<DATE-OF-FILING-DATE-CHANGE>20081029
<SUBJECT-COMPANY>
<COMPANY-DATA>
<CONFORMED-NAME>ENVIRONMENTAL POWER CORP
<CIK>0000805012
<ASSIGNED-SIC>4991
<IRS-NUMBER>042782065
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>FWP
<ACT>34
<FILE-NUMBER>333-152807
<FILM-NUMBER>081147199
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>120 WHITE PLAINS RD
<STREET2>SUITE 610
<CITY>TARRYTOWN
<STATE>NY
<ZIP>10591-5546
<PHONE>914-631-1435
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>120 WHITE PLAINS RD
<STREET2>SUITE 610
<CITY>TARRYTOWN
<STATE>NY
<ZIP>10591-5546
</MAIL-ADDRESS>
</SUBJECT-COMPANY>
<FILED-BY>
<COMPANY-DATA>
<CONFORMED-NAME>ENVIRONMENTAL POWER CORP
<CIK>0000805012
<ASSIGNED-SIC>4991
<IRS-NUMBER>042782065
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>FWP
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>120 WHITE PLAINS RD
<STREET2>SUITE 610
<CITY>TARRYTOWN
<STATE>NY
<ZIP>10591-5546
<PHONE>914-631-1435
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>120 WHITE PLAINS RD
<STREET2>SUITE 610
<CITY>TARRYTOWN
<STATE>NY
<ZIP>10591-5546
</MAIL-ADDRESS>
</FILED-BY>
<DOCUMENT>
<TYPE>FWP
<SEQUENCE>1
<FILENAME>dfwp.htm
<DESCRIPTION>FREE WRITING PROSPECTUS
<TEXT>
<HTML><HEAD>
<TITLE>Free Writing Prospectus</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Issuer Free Writing Prospectus </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT
FACE="Times New Roman" SIZE="2">Filed Pursuant to Rule&nbsp;433 </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Registration Statement on Form S-3 No.&nbsp;333-152807 </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>SUMMARY OF PROPOSED KEY TERMS </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman"
SIZE="2"><B>October&nbsp;29, 2008 </B></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="11%"></TD>
<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="40%"></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD WIDTH="41%"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Issuer:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">Environmental Power Corporation (NASDAQ: EPG)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Securities Offered:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">Convertible Notes due January&nbsp;1, 2014 (the &#147;Notes&#148;)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Interest Rate:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">13% per annum</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Conversion Security:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">Common Stock, $0.01 per share</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Minimum Conversion Price:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">$5.40 per share</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Conversion<BR>Price:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"> <P STYLE="border-bottom:1px solid #000000;width:57pt"><FONT FACE="Times New Roman" SIZE="1"><B>Conversion Date</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1"><B>Greater of Minimum</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000;width:76pt"><FONT
FACE="Times New Roman" SIZE="1"><B>Conversion Price and:</B></FONT></P></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">From the Issue Date through December&nbsp;31, 2009</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">85% of market price</FONT></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">From January&nbsp;1, 2010 through December&nbsp;31, 2010</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">87.5% of market price</FONT></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">From January&nbsp;1, 2011 through December&nbsp;31, 2011</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">90% of market price</FONT></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">From January&nbsp;1, 2012 through December&nbsp;31, 2012</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">92.5% of market price</FONT></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">From January&nbsp;1, 2013 through December&nbsp;31, 2013</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">95% of market price</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Minimum Offering:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">$10,000,000</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Anticipated Maximum Offering:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">$25,000,000 (subject to increase)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Offering&nbsp;Price:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">Par</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Other Terms:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">The Notes are subject to optional and mandatory redemption and mandatory conversion in certain circumstances, as well as other terms more fully described in the preliminary
Prospectus Supplement relating to this offering.</FONT></TD></TR>
</TABLE> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>The issuer has filed a registration statement (including a prospectus) with the SEC for the offering to which
this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer and this offering. You may get these
documents for free by visiting EDGAR on the SEC website at </B><B><I><U>www.sec.gov</U></I></B><B>. Alternatively the issuer and the underwriter will arrange to send you the prospectus if you request it by calling (888)&nbsp;884-8339. </B>
</FONT></P>
</BODY></HTML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
