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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:  August 16, 2004


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