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                                                                     EXHIBIT 5.1


                                             December 15, 1998


AstroPower, Inc.
Solar Park
Newark, Delaware 19716-2000

Ladies and Gentlemen:

  We have acted as counsel to AstroPower, Inc., a Delaware corporation (the
"Company"), in connection with the registration under the Securities Act of 1933
(the "Act") of an aggregate of 500,000 shares (the "Shares") of the Company's
common stock, $.01 par value (the "Common Stock"), which shares may be issued to
the AstroPower, Inc. 401(k) Savings Plan by the Company as Matching
Contributions or may be purchased directly from the Company at the discretion of
a Plan Participant as an alternative investment option and which may be re-
offered for sale by the Trustees of the Trust Fund which holds the assets of the
Plan acting on behalf of the Plan or for the account of a Participant.

  In connection therewith, we have examined or considered originals or copies,
certified or otherwise identified to our satisfaction, of the Amended and
Restated Certificate of Incorporation of the Company, the Amended and Restated
By-laws of the Company, the Plans, records of relevant corporate proceedings
with respect to the offering of the Shares and such other documents, instruments
and corporate records as we have deemed necessary or appropriate for the
expression of the opinions contained herein.  We have also reviewed the
Company's Registration Statement on Form S-8 (the "Registration Statement") to
be filed with the Securities and Exchange Commission with respect to the Shares.

  We have assumed the authenticity and completeness of all records, certificates
and other instruments submitted to us as originals, the conformity to original
documents of all records, certificates and other instruments submitted to us as
copies, the authenticity and completeness of the originals of those records,
certificates and other instruments submitted to us as copies and the correctness
of all statements of fact contained in all records, certificates and other
instruments that we have examined.

  Based on the foregoing and having regard for such legal considerations as we
have deemed relevant, we are of the opinion that the Shares have been duly and
validly authorized for the issuance and, that the Shares issued and outstanding
are and that the Shares to be issued, when issued in accordance with the terms
of the applicable Plan will be, duly and validly issued, fully paid and
nonassessable.
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AstroPower, Inc.
December 15, 1998
Page 2



  The foregoing opinion is limited to the federal law of the United States of
America and the General Corporation Law of the State of Delaware, and we are
expressing no opinion as to the effect of the laws of any other jurisdiction.

  We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name under the caption "Item 5.
Interests of Named Experts and Counsel" in the Registration Statement and under
the heading "Legal Matters" in the Prospectus.

                                             Sincerely,

                                             Opton Handler Feiler & Landau, LLP


                                             By:_______________________
                                                     Peter Landau
