1

                                                                    EXHIBIT 5.01

                                  June 15, 2001


DeMarco Energy Systems of America, Inc.
12885 Highway 183
Suite 108-A
Austin, Texas 78750

         Re:      Form SB-2 - DeMarco Energy Systems of America, Inc.

Gentlemen:

         As legal counsel to DeMarco Energy Systems of America, Inc., a Utah
corporation (the "Company"), we have examined the Articles of Incorporation and
Bylaws of the Company as well as such other documents and proceedings as we have
considered necessary for the purposes of this opinion. We have also examined and
are familiar with the Company's registration statement on Form SB-2, as amended
by Amendment No. 1 and Amendment No. 2 (the "Registration Statement"), as filed
with the Securities and Exchange Commission under the Securities Act of 1933, as
amended (the "Act"), relating to registration of 22,826,086 shares of the
Company's common stock, par value $.0001 per share (the "Common Shares"), which
may be offered or sold by the Selling Stockholders referred to in the
Registration Statement.

         Based upon the foregoing, and having regard to legal considerations
which we deem relevant, we are of the opinion that the Common Shares are, or
will be upon issuance in connection with the conversion of the underlying 10%
secured convertible debentures, legally issued, fully paid and non-assessable.

         We hereby consent to the inclusion of this opinion letter as an exhibit
to the Registration Statement and the reference to our Firm under the caption
"Legal Matters." In giving such consent, we do not hereby admit that we are in
the category of persons whose consent is required under Section 7 of the Act.

                                        Very truly yours,

                                        Locke Liddell & Sapp LLP