Filed by Plug Power Inc. pursuant
                                   to Rule 425 under the Securities Act of 1933,
                             as amended, and deemed filed pursuant to Rule 14a-6
                              of the Securities Exchange Act of 1934, as amended

                                                  Subject Company: H Power Corp.
                                                  Commission File No. 333-101567

     On March 21, 2003, Plug Power Inc. and H Power Corp. disseminated the
following press release and posted the press release on their respective
internet websites:

FOR IMMEDIATE RELEASE

Contacts:
David Neumann
Chief Financial Officer
Plug Power Inc.
Phone: (518) 782-7700 ext. 1161

Cynthia M. Mahoney
Manager, Public Relations & Marketing
Phone: (518) 782-7700 ext. 1973
Web site: http://www. plugpower.com
                 ------------------

William L. Zang
Chief Financial Officer
H Power Corp.
Phone: (973) 450-4400 ext. 5513
Web site: http://www.hpower.com
                 --------------

   PLUG POWER INC. AND H POWER CORP. ANNOUNCE DETERMINATION OF EXCHANGE RATIO

LATHAM, N.Y. and BELLEVILLE, N.J. - March 21, 2003 -- Plug Power Inc. (NASDAQ:
PLUG) and H Power Corp. (NASDAQ: HPOW) today announced that the estimated
exchange ratio for Plug Power's merger transaction with H Power has been
determined. H Power stockholders will receive 0.8305 shares of Plug Power
common stock for each share of H Power common stock held immediately prior to
the transaction, assuming that the merger closes on March 25, 2003 after the
meetings of stockholders of both companies scheduled that day to consider
approval of the merger transaction.




Pursuant to the terms of the merger agreement between Plug Power and H Power,
and as described in the joint proxy statement/prospectus delivered to each
company's stockholders, this exchange ratio calculation is subject to a number
of variables, including the Transaction Value Price and the Average Parent
Common Stock Price (as each of these terms are defined in the merger agreement
and explained in the joint proxy statement/prospectus). The Transaction Value
Price has been determined to be $47.3 million, which is based upon the
determination that Net Cash, a defined term in the merger agreement that bears
upon the calculation of Transaction Value Price, is $33.3 million. The merger
agreement and the joint proxy statement/prospectus contain a detailed
description of the variables that comprise Net Cash, as well as a summary of the
process employed by Plug Power and H Power to arrive at the final Net Cash
amount.

A further variable to be determined is the Average Parent Common Stock Price,
which is defined in the merger agreement as the daily volume weighted average
price of Plug Power common stock for 10 trading days selected by lot out of the
20 trading days ending on and including the second trading day before the
closing of the merger (or March 21, 2003, assuming the merger closes on March
25, 2003). The estimated Average Parent Common Stock Price is determined to be
$5.08 per share. Since the estimated Average Parent Common Stock Price is less
than $5.29, the collar provisions of the merger agreement adjust the Average
Parent Common Stock Price to $5.29 for purposes of determining the estimated
exchange ratio.

Plug Power designs, develops and manufactures on-site electric power generation
systems utilizing Proton Exchange Membrane (PEM) fuel cells for stationary
applications. Plug Power's fuel cell systems are expected to be sold globally
through a joint venture with General Electric and through DTE Energy
Technologies in a four-state territory, consisting of Michigan, Illinois, Ohio
and Indiana. Plug Power's headquarters are located in Latham, N.Y., with offices
in Washington, D.C., and The Netherlands.

H Power Corp. is a fuel cell manufacturing and development company, which has
designed PEM fuel cell systems to provide electricity for a wide range of
stationary and portable applications. H Power recently launched the commercial
version of the EPAC500, a 500-watt, fuel cell-based power source, and has
developed pre-commercial stationary fuel cell products in the 4.5 kilowatt
range.

                                       ###

This release contains statements about Plug Power, H Power, and the proposed
acquisition that are not historical facts and are considered forward-looking
within the meaning of the Private Securities Litigation Reform Act of 1995.
These statements are based upon current expectations, forecasts and assumptions
that are subject to risks, uncertainties and other factors that could cause
actual outcomes and results to differ materially from those indicated by these
forward-looking statements. These risks, uncertainties and other factors
include, but are not limited to: the satisfaction of the conditions to closing,
including receipt of shareholder and regulatory approvals; the expected closing
date of the transaction; the risk that the transaction will not close; the risk
that Plug Power will not integrate and restructure the acquired business
successfully; the risk that Plug Power will incur unanticipated costs to
integrate and restructure the acquired business; the risk that H Power will
require more cash than anticipated prior to closing; fluctuation in the trading
price and volume of Plug Power's common stock; the risk that continuity of H
Power operations will be further disrupted in the event the transaction does not
close; Plug Power's ability to develop a commercially viable fuel cell system;
the cost and time required for Plug Power to develop fuel cell systems; market
acceptance of Plug Power's fuel cell systems; Plug Power's reliance on its
relationship with certain affiliates of General Electric; Plug Power's ability
to perform on its multi-generation product plan in a manner satisfactory to
GEFCS and DTE; Plug Power's ability to manufacture fuel cell systems on a
commercial

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basis; competitive factors, such as price competition, competition from other
power technologies and competition from other fuel cell companies; the cost and
availability of components and parts for Plug Power's fuel cell systems; the
ability to raise and provide the necessary capital to develop, manufacture and
market Plug Power's fuel cell systems; Plug Power's ability to lower the cost of
its fuel cell systems and demonstrate their reliability; the cost of complying
with current and future governmental regulations; and other risks and
uncertainties discussed under the heading "Risk Factors" in Plug Power's annual
report on Form 10-K for the fiscal year ended December 31, 2001, under the
heading "Risk Factors" in H Power's annual report on Form 10-K for the fiscal
year ended May 31, 2002, under the heading "Risk Factors" in Plug Power's and H
Power's joint proxy statement/prospectus on Form S-4 filed with the Securities
and Exchange Commission ("SEC") on February 12, 2003, as well as in the reports
Plug Power and H Power file from time to time with SEC. Except as required by
the Federal securities laws, Plug Power and H Power undertake no duty to update
or revise publicly any forward-looking statements.

Plug Power has filed relevant documents in connection with the transaction with
the SEC, including a registration statement on Form S-4 containing a joint proxy
statement/prospectus. WE URGE INVESTORS AND SECURITY HOLDERS TO READ THE
REGISTRATION STATEMENT, THE JOINT PROXY STATEMENT/PROSPECTUS AND ANY OTHER
RELEVANT DOCUMENTS THAT ARE FILED WITH THE SEC WHEN THEY BECOME AVAILABLE
BECAUSE THEY CONTAIN, OR WILL CONTAIN, IMPORTANT INFORMATION ABOUT PLUG POWER, H
POWER AND THE TRANSACTION. Investors will be able to obtain these documents free
of charge at the SEC's website, (http://www.sec.gov) after they are filed. These
documents may also be obtained free of charge by directing a request to the Plug
Power or H Power contacts listed at the beginning of this news release.

Plug Power, its directors and certain of its executive officers may be
considered participants in the solicitation of proxies in connection with the
proposed transaction. Information about the directors and executive officers of
Plug Power and their ownership of Plug Power stock is set forth in Plug Power's
proxy statement for its 2002 annual meeting of shareholders, which was filed
with the SEC on April 24, 2002. Additional information about the interests of
these participants may be obtained from reading the joint proxy
statement/prospectus. H Power, its directors and certain of its executive
officers may be considered participants in the solicitation of proxies in
connection with the proposed transaction. Information about the directors and
officers of H Power and their ownership of H Power stock is set forth in H
Power's proxy statement for its 2002 annual meeting of shareholders, which was
filed with the SEC on September 13, 2002. Additional information about the
interests of these participants may be obtained from reading the joint proxy
statement/prospectus.


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