TMEN ThermoEnergy Corp (CE)

CUSIP No. 883906406


(1) Name of Reporting Person
 S.S. or I.R.S. Identification No. of Above Person

 David Gelbaum, Trustee, The Quercus Trust

(2) Check the Appropriate Box if a Member of a Group (See Instructions)
 (A) /X/
 (B) /_/

(3) SEC Use Only

 (4) Source of Funds (See Instructions)

 PF

(5) Check if Disclosure of Legal Proceedings is Required Pursuant to Items
 2(d) or 2(e)
 /_/

(6) Citizenship or Place of Organization

 U.S.

 (7) Sole Voting Power
 -0-

Number of Shares (8) Shared Voting Power
Beneficially Owned 23,333,334
by Each Reporting
Person With (9) Sole Dispositive Power
 -0-

 (10) Shared Dispositive Power
 23,333,334

(11) Aggregate Amount Beneficially Owned by Each Reporting Person

 23,333,334

(12) Check if the Aggregate Amount in Row (11) Excludes Certain Shares
 (See Instructions) /_/

(13) Percent of Class Represented by Amount in Row (11)

 35.0% (1)

(14) Type of Reporting Person (See Instructions)

 IN

-------------------------
(1) Based on 65,676,235 shares of Common Stock, par value $0.001 per share
("Common Stock") outstanding, calculated in accordance with Rule 13d.


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CUSIP No. 883906406


(1) Name of Reporting Person
 S.S. or I.R.S. Identification No. of Above Person

 Monica Chavez Gelbaum, Trustee, The Quercus Trust

(2) Check the Appropriate Box if a Member of a Group (See Instructions)
 (A) /X/
 (B) /_/

(3) SEC Use Only

(4) Source of Funds (See Instructions)

 PF

(5) Check if Disclosure of Legal Proceedings is Required Pursuant to Items
 2(d) or 2(e)
 /_/

(6) Citizenship or Place of Organization

 U.S.

 (7) Sole Voting Power
 -0-

Number of Shares (8) Shared Voting Power
Beneficially Owned 23,333,334
by Each Reporting
Person With (9) Sole Dispositive Power
 -0-

 (10) Shared Dispositive Power
 23,333,334

(11) Aggregate Amount Beneficially Owned by Each Reporting Person

 23,333,334

(12) Check if the Aggregate Amount in Row (11) Excludes Certain Shares
 (See Instructions) /_/

(13) Percent of Class Represented by Amount in Row (11)

 35.0% (1)

(14) Type of Reporting Person (See Instructions)

 IN

-------------------------
(1) Based on 65,676,235 shares of Common Stock, par value $0.001 per share
("Common Stock") outstanding, calculated in accordance with Rule 13d.

 3

CUSIP No. 883906406


(1) Name of Reporting Person
 S.S. or I.R.S. Identification No. of Above Person

 The Quercus Trust

(2) Check the Appropriate Box if a Member of a Group (See Instructions)
 (A) /X/
 (B) /_/

(3) SEC Use Only

(4) Source of Funds (See Instructions)

 PF

(5) Check if Disclosure of Legal Proceedings is Required Pursuant to Items
 2(d) or 2(e) /_/

(6) Citizenship or Place of Organization

 U.S.

 (7) Sole Voting Power
 -0-

Number of Shares (8) Shared Voting Power
Beneficially Owned 23,333,334
by Each Reporting
Person With (9) Sole Dispositive Power
 -0-

 (10) Shared Dispositive Power
 23,333,334

(11) Aggregate Amount Beneficially Owned by Each Reporting Person

 23,333,334

(12) Check if the Aggregate Amount in Row (11) Excludes Certain Shares
 (See Instructions) /_/

(13) Percent of Class Represented by Amount in Row (11)

 35.0% (1)

(14) Type of Reporting Person (See Instructions)

 OO

-------------------------
(1) Based on 65,676,235 shares of Common Stock, par value $0.001 per share
("Common Stock") outstanding, calculated in accordance with Rule 13d.

 4

CUSIP No. 883906406


Item 1. Security and Issuer

 This Amendment No. 2 to Schedule 13D (this "Amendment No. 2") amends
and restates, where indicated, the statement on Schedule 13D relating to the
Common Stock of the Issuer filed by The Quercus Trust, David Gelbaum and Monica
Chavez Gelbaum (the "Reporting Persons") with the Securities and Exchange
Commission on December 31, 2007 (the "Initial Schedule 13D") and prior
amendments thereto. Capitalized terms used in this Amendment No. 2 but not
otherwise defined herein have the meanings given to them in the Initial Schedule
13D or prior amendments thereto.

Item 4. Purpose of Transaction

 This Amendment No. 2 is being made to disclose that the Reporting
Persons have proposed to the Issuer changes in the composition of the board of
directors (the "Board"). The Reporting Persons also believe that Issuer should
review its management and other personnel needs. These efforts would be intended
to result in stronger oversight by the Board and to improve the ability of
Issuer to execute its business plan.

 If Issuer does not make changes to Board and review other operational
requirements, the Reporting Persons may take other actions to effect such
changes, either at a meeting of stockholders or an action by written consent of
shareholders to remove and/or elect directors and/or to amend the Issuer's
bylaws to eliminate the classification of the Board.

 One of Issuer's principal technologies is a chemical-based ammonia
removal process ("ARP") system to be integrated into water treatment plants
which is believed to have strong competitive advantages over currently used
biological ammonia removal systems. Currently, Issuer is negotiating a contract
(the "NYC Contract") to install an ARP system in Jamaica Bay for New York City.
The system would be the initial commercial project for the ARP technology, and
the Issuer hopes to be able develop additional ARP systems for the New York City
as well as other waste water systems throughout the country and internationally.

 The Reporting Persons believe that it is essential that the Company
effectively perform its obligations under the NYC Contract, if received, and
that Issuer have in place executive and project management personnel, controls
and procedures necessary to adequately insure that it will be able to
effectively perform its duties under the NYC Contract, and to manage the project
procurement process that will be required for future success. It is believed
that a failure to effectively perform under the NYC Contract is likely to have a
material, adverse effect on the Issuer and its results of operations, and, in
particular, its ability to market and develop the ARP at other waste water
facilities. As a principal shareholder of the Issuer, the Reporting Persons
desire to take steps to assure the successful completion of the NYC Contract.

 The Reporting Persons are currently the beneficial owners of 35% of
outstanding Common Stock. The Reporting Persons have acquired securities of the
Issuer in a PIPE offering in December 2007 and a second PIPE offering in
September 2008. In the 2008 PIPE offering, (1) the Reporting Persons purchased
from the Issuer for $2.0 million: (a) a convertible promissory note in the
principal amount of $2.0 million due September 30, 2013, with a conversion price
of $0.75 per share, and (b) a warrant to purchase up to 4 million shares of
Common Stock expiring September 30, 2013, and (2) the Reporting Persons agreed
to purchase in the future for $5.0 million: (the "$5 Million Investment"): (a) a
convertible promissory note in the principal amount of $5.0 million, and (b) a
warrant to purchase 10 million shares of Common Stock. The exercise price of
both of the warrants described above is $0.525 per share.

 One of the conditions to the consummation of the $5 Million Investment
is that Issuer enter into the New York City Contract on specified terms, which
has not occurred to date. In lieu of the $5 Million Investment and due to the
Issuer's need for additional capital, the Reporting Persons have made a number
of proposals to the Issuer with respect to an alternative investment in the
Issuer. These included a proposal on April 13, 2009, to make a two part, $5.0
million investment, including a $2.0 million investment prior to execution of
the NYC Contract, on terms that would fix the number of directors on the Board
at seven persons, three of which would be designated by the Reporting

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CUSIP No. 883906406


Persons and two of whom would be existing directors Alex Fassbender and Jim
Wood. Alex Fassbender is the Chief Technical Officer of the Company and Jim Wood
is the President and Chief Executive Officer of Babcock Power Inc., with whom
the Issuer has entered into a joint venture agreement with respect to its zero
air emission power plant technology. The Reporting Persons have not determined
who it would designate to be directors of the Issuer. In addition, the Reporting
Person would obtain an approval right with respect to certain transactions by
the Issuer.

 On April 20, 2009, the Issuer rejected the Reporting Persons' proposal
and provided a counter offer, which the Reporting Persons have rejected.

 The Reporting Persons continue to seek to effect the changes described
above. The Reporting Persons have not determined but reserve the right to
exercise and/or convert the warrants and notes described above, purchase
additional shares of Common Stock in the open market or in private transactions,
or take other actions to increase the Reporting Persons' economic stake and
voting influence over the Issuer. The Reporting Persons may also from time to
time determine to sell Common Stock and other securities in the open market or
in private transactions.

 Other than as described above, the Reporting Persons do not have any
present plans or proposals which relate to or that would result in any of the
actions or transactions described in paragraphs (a) through (j) of Item 4 of the
instructions to Schedule 13D. However, the Reporting Persons reserve the right
from time to time to formulate plans or proposals regarding the Issuer or any of
its securities and to carry out any of the actions or transactions described in
paragraphs (a) through (j) of Item 4 of the instructions to Schedule 13D, to the
extent they deem advisable.

Item 5. Interest in Securities of the Issuer

 (a) As of the date of this Amendment No. 2, the Reporting Persons
beneficially own a total of 23,333,334 shares of Common Stock, which are held of
record by the Trust. The 23,333,334 shares include 6,666,667 shares of Common
Stock, 14,000,000 shares of Common Stock issuable upon exercise of warrants, and
2,666,667 shares of Common Stock issuable upon conversion of a convertible
promissory note.

 (b) Each of David Gelbaum and Monica Chavez Gelbaum, acting alone, has
the power to exercise voting and investment control over the shares of Common
Stock owned by the Trust.

 (c) Not applicable.

 (d) Not applicable.

 (e) Not applicable.

Item 6. Contracts, Arrangements, Understandings or Relationships With Respect
 to Securities of the Issuer

 Pursuant to the Power of Attorney filed as Exhibit "B" to Amendment No.
1 to Schedule 13D filed on August 24, 2007 with respect to the issuer Emcore
Corp., David Gelbaum has been appointed as Monica Chavez Gelbaum's
Attorney-In-Fact.

Item 7. Material to Be Filed as Exhibits

 Exhibit A: Agreement Regarding Joint Filing of Amendment
 No. 2 to Schedule 13D

 Exhibit B: Proposal Regarding Corporate Governance


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CUSIP No. 883906406



SIGNATURE

 After reasonable inquiry and to the best of its knowledge and belief,
each of the undersigned certifies that the information set forth in this
statement is true, complete and correct and agrees that this statement may be
filed jointly with the other undersigned parties.



Dated: April 27, 2009 /s/ David Gelbaum
 -----------------------------------------------
 David Gelbaum, Co-Trustee of The Quercus Trust



 /s/ David Gelbaum, As Attorney-in-fact for
 Monica Chavez Gelbaum
 -----------------------------------------------
 Monica Chavez Gelbaum, Co-Trustee of The
 Quercus Trust


 /s/ David Gelbaum
 -----------------------------------------------
 The Quercus Trust, David Gelbaum, Co-Trustee
 of The Quercus Trust

GOVERNANCE: The Quercus Trust ("Quercus") will have the right to appoint
 not fewer than 40% of the members of the board of directors of
 ThermoEnergy Corporation (the "Company"), which board shall
 consist of no more than seven members unless otherwise agreed
 by Quercus, and holders of the Common Stock shall have the
 right to appoint the remaining members of the board of
 directors, provided that two of the directors elected by
 holders of the Common Stock shall initially be Alex Fassbender
 and Jim Wood. All actions of the board shall require the
 approval of at least one director appointed by Quercus.
 Quercus shall vote on all other matters on an as-converted
 basis together with the Common Stock and not as a separate
 class, except as specifically provided herein or as otherwise
 required by law.

 As long as at least $2 million aggregate principal amount of
 the convertible notes held by Quercus are outstanding, all
 "Major Decisions" shall require the approval of at least
 two-thirds of the members of the board of directors present at
 a meeting duly called for the purpose at which a quorum is
 present. The term "Major Decisions" shall include any decision
 to (a) issue equity securities at a price below the conversion
 price of the notes held by Quercus at the time, (b) incur
 indebtedness for borrowed money (subject to customary
 exceptions to be agreed upon), (c) enter into any merger or
 other agreement involving a sale of all or substantially all
 the business or assets of the Company and its subsidiaries,
 (d) enter into, terminate, or waive any material provision of
 any material agreement, (e) retain independent counsel or
 accountants (other than for the purpose of evaluating
 transactions in which Quercus has a material interest).