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                                                                    EXHIBIT 31.1

                                  CERTIFICATION

                CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER AND
                     PRINCIPAL FINANCIAL OFFICER PURSUANT TO
                 SECURITIES EXCHANGE ACT RULES 13A-14 AND 15D-14
                       AS ADOPTED PURSUANT TO SECTION 302
                        OF THE SARBANES-OXLEY ACT OF 2002


I, Dennis C. Cossey, certify that:

1. I have reviewed this quarterly report on Form 10-QSB of ThermoEnergy
Corporation;

2. Based on my knowledge, this quarterly report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this quarterly
report;

3. Based on my knowledge, the financial statements, and other financial
information included in this quarterly report, fairly present in all material
respects the financial condition, results of operations and cash flows of the
registrant as of, and for, the periods presented in this quarterly report;

4. I am the registrant's sole certifying officer and I am responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and, accordingly,
I have:

a) designed such disclosure controls and procedures, or caused such disclosure
controls and procedures to be designed under my supervision, to ensure that
material information relating to the registrant, including its consolidated
subsidiaries, is made known to me by others within those entities, particularly
during the period in which this quarterly report is being prepared;

b) evaluated the effectiveness of the registrant's disclosure controls and
procedures and presented in this quarterly report my conclusions about the
effectiveness of the disclosure controls and procedures, as of the end of the
period covered by this quarterly report based on such evaluation; and

c) disclosed in this quarterly report any change in the registrant's internal
control over financial reporting that occurred during the registrant's most
recent fiscal quarter (the registrant's forth quarter in the case of an annual
report) that has materially affected or is reasonably likely to materially
affect, the registrant's internal control over financial reporting; and

5. I have disclosed, based on my most recent evaluation of internal control over
financial reporting, to the registrant's auditors and the audit committee of
registrant's board of directors (or persons performing the equivalent
functions):

a) all significant deficiencies in the design or operation of internal control
which are reasonably likely to adversely affect the registrant's ability to
record, process, summarize and report information; and

b) any fraud, whether or not material, that involves management or other
employees who have a significant role in the registrant's internal control over
financial reporting.


Date: November 15, 2004


                                            /s/    Dennis C. Cossey
                                            -----------------------------------
                                            Dennis C. Cossey
                                            Chief Executive Officer and
                                            Principal Financial Officer