EXHIBIT 5.1



                (WALLER LANSDEN DORTCH & DAVIS, LLP LETTERHEAD)


                                January 31, 2006


Capstone Turbine Corporation
21211 Nordhoff Street
Chatsworth, CA 91311

           Re:  Registration Statement on Form S-8

Ladies and Gentlemen:

        We are acting as counsel to Capstone Turbine Corporation, a Delaware
corporation (the "Company"), in connection with the registration under the
Securities Act of 1933 (the "Act") pursuant to a Registration Statement on Form
S-8 (the "Registration Statement") of an aggregate of 3,880,000 shares of the
Company's Common Stock, par value $0.001 per share and the related rights to
purchase Series A Junior Participating Preferred Stock of the Company, par value
$0.001 per share (the "Shares").

        In connection with this opinion, we have examined and relied upon such
records, documents and other instruments as in our judgment are necessary and
appropriate in order to express the opinion hereinafter set forth, and have
assumed the genuineness of all signatures, the authenticity of all documents
submitted to us as originals, and the conformity to original documents of all
documents submitted to us as certified or photostatic copies.

        Based upon the foregoing, we are of the opinion that the Shares, when
issued and delivered in the manner and on the terms described in the
Registration Statement, will be validly issued, fully paid and non-assessable.

        We hereby consent to the filing of this opinion with the Securities and
Exchange Commission as Exhibit 5.1 to the Registration Statement. This consent
is not to be construed as an admission that we are a party whose consent is
required to be filed with the Registration Statement under the provisions of the
Act or the rules and regulations of the Securities and Exchange Commission
promulgated thereunder.


                                       Very truly yours,


                                       /s/ Waller Lansden Dortch & Davis, LLP