Exhibit 10.5

STOCK PLEDGE AND SECURITY AGREEMENT

THIS STOCK PLEDGE AND SECURITY AGREEMENT (the “Agreement”) is made and entered
into effective as of the 26th day of June, 2008, by and between Nexxus Lighting,
Inc., a Delaware corporation (the “Pledgor”) and Jay Weil, as collateral agent
(“Collateral Agent”) for the secured parties (“the Secured Parties”) pursuant to
that certain Collateral Agent Agreement, dated of even date herewith, among
Pledgor, Collateral Agent and the Secured Parties (the “Collateral Agent
Agreement”).

BACKGROUND

A. Pursuant to that certain Note and Warrant Purchase Agreement, dated of even
date herewith, between the Company and the purchasers set forth on Schedule I
thereto (the “Purchase Agreement”), the Pledgor is selling, and the Secured
Parties are purchasing, Secured Promissory Notes Due December 2009 in the
aggregate principal amount not to exceed $3,500,000 (the “Notes”).

B. In order to secure the timely payment and performance of the Notes, the
Pledgor desires to grant the Secured Parties a first-in-priority, perfected and
continuing security interest in the shares of common stock (the “Shares”) the
Pledgor owns in Lumificient Corporation, a Minnesota corporation and a
wholly-owned subsidiary of the Pledgor (“Lumificient”).

C. The continuing Security Interest in the Shares shall be evidenced by this
Agreement. Capitalized terms used, but not defined, in this Agreement have the
meanings set forth in the Purchase Agreement.

NOW, THEREFORE, for and in consideration of the mutual promises and covenants
contained herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

AGREEMENT

1. Recitals and Defined Terms. The parties hereto acknowledge that the
aforementioned recitals are true and correct and agree that such recitals,
together with the definitions set forth therein and in the preamble to this
Agreement, are hereby incorporated into this Agreement by this reference.

2. Additional Shares. All references to the Shares shall be appropriately
adjusted to reflect any stock split, distribution, recapitalization or other
similar arrangement affecting the Shares after the date of this Agreement. In
the event that the Pledgor receives, or becomes entitled to, any property
(whether real or personal, tangible or intangible) in connection with or related
to the Shares in any way, then any such property shall be considered Shares
under this Agreement.

3. Creation of Security Interest. Pledgor hereby affirms, acknowledges,
ratifies, grants and assigns in favor of the Secured Parties a first, prior and
sole lien and security interest (the “Security Interest”) in the Shares and in
all accessions, substitutions, replacements and proceeds thereof, including
without limitation, whether by law, merger or exchange, to secure

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the Obligations (as defined below). Pledgor hereby warrants and represents to
the Secured Parties that the Shares are owned by the Pledgor free and clear of
any liens, charges or encumbrances other than those imposed by securities laws
and this Agreement.

For purposes of this Agreement the term “Obligations” shall mean: (a) all
indebtedness, liabilities and obligations of Pledgor to the Secured Parties
under the Notes, and any note or notes hereafter issued in substitution or
replacement thereof, (b) all obligations of the Pledgor under this Agreement and
(c) in the foregoing cases whether due or to become due, and whether now
existing or hereafter arising or incurred.

4. Perfection of Security Interest. The Security Interest in the Shares shall be
perfected by the Collateral Agent taking possession of the certificates
representing the Shares. The Collateral Agent shall hold such securities on
behalf of the Secured Parties.

5. Proxy. Pledgor hereby irrevocably constitutes and appoints the Collateral
Agent, whether or not the Shares have been transferred into the name of the
Secured Parties, as the Pledgor’s proxy, with full power to (a) attend meetings
concerning the Shares held after the date of this Agreement and, to vote the
Shares at those meetings in such manner as the Collateral Agent shall, in his
sole and absolute discretion, deem appropriate, (b) consent, in the sole and
absolute discretion of the Collateral Agent, to any action by or concerning
Pledgor for which consent of the stockholders of Lumificient is or may be
necessary or appropriate, and (c) do all things that Pledgor could do as a
securities holder of Lumificient, giving and granting unto the Collateral Agent
full power of substitution and revocation. Notwithstanding the provisions
contained in the preceding sentence (hereinafter referred to as the “Proxy
Rights”), neither the Collateral Agent nor the Secured Parties, or any of them,
shall have the right to perform, exercise, take or assert any of the Proxy
Rights unless and until there shall have occurred an Event of Default (as that
term is defined below). Except upon the occurrence and during the continuation
of an Event of Default, Pledgor shall be entitled to exercise any and all voting
and/or consensual rights and powers accruing to an owner of the Shares or any
part thereof for any purpose. Pledgor hereby revokes all proxies heretofore
given and agrees not to grant any proxy to any person or persons with respect to
the Shares other than as granted herein for so long as this Agreement is in
force.

6. Ordinary Care by the Secured Parties. The Secured Parties and/or the
Collateral Agent shall use ordinary care in the custody and preservation of the
Shares in their possession.

7. Event of Default. An event of default shall occur upon the happening of any
of the following (each, an “Event of Default”):

(a) Default by Pledgor in the performance of any of the obligations contained
herein after receipt by Pledgor of notice in writing of such default (including,
a brief description of the nature of the default) and failure by Pledgor to cure
such default within thirty days after the receipt of such notice;

(b) An Event of Default under the Notes; or

(c) The transfer or encumbrance, by any means, of any interest in the Shares
other than in favor of the Secured Parties.

8. Remedies. Upon the occurrence and during the continuation of an Event of
Default, the Secured Parties may, at their option, without notice to or demand
upon the Pledgor,

 

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take the Shares in the Secured Parties’ own names, on a pro rata or any other
basis agreed to by the Secured Parties, and dispose of that portion of the
Shares as may be necessary to satisfy the Pledgor’s Obligations agreed to by the
Secured Parties, including, without limitation, the outstanding principal amount
of the Notes and all accrued interest thereon (as provided in the Notes). In
addition to the rights and remedies provided for herein, or otherwise available
to the Secured Parties, the Secured Parties (and the Collateral Agent acting on
their behalf) shall have all the rights and remedies of a secured party under
the Uniform Commercial Code (“UCC”) in effect in the State of Delaware at the
time, including the right to sell the Shares at public or private sale as
provided by and in accordance with the UCC.

9. Covenants of Pledgor. During the term of this Agreement:

(a) Pledgor shall not sell, assign, transfer, hypothecate, or otherwise dispose
of the Shares, or any interest therein, encumber the Shares or any interest
therein, or contract to do any of the foregoing; and

(b) Pledgor shall not take any action with respect to the Shares that is
inconsistent with the provisions or purpose of this Agreement or that would
adversely affect the rights of Secured Parties or the Collateral Agent under
this Agreement.

10. Collateral Agent. The rights of the Secured Parties in the Shares will be
exercisable by Collateral Agent as agent for Secured Parties pursuant to the
Purchase Agreement. In such capacity, from time to time and at any time,
Collateral Agent may in his sole discretion take any and all actions, exercise
any and all rights and remedies, give any and all waivers and forbearances, and
make any and all determinations and elections that the Secured Parties are
entitled to exercise under this Agreement and the Notes. Pledgor will be
entitled to rely solely on the actions of Collateral Agent as binding all
Secured Parties.

11. Termination of this Security Interest and Agreement. This Agreement and the
Security Interest created hereby shall terminate immediately on the satisfaction
of all of the Company’s Obligations and the Collateral Agent shall immediately
thereafter return to the Pledgor all certificates, and related stock powers,
with respect to the Shares directly or indirectly in his possession or control.

12. Miscellaneous Provisions.

(a) Interpretation. This Agreement will be interpreted in accordance with, and
subject to the provisions of, the Purchase Agreement applicable to all
Transaction Documents. Without limiting the foregoing, this Agreement is
governed by Delaware law.

(b) Effect of Invalidity of Particular Provisions. The unenforceability or
invalidity of any provision or provisions of this Agreement shall not render any
other provision or provisions herein contained unenforceable or invalid.

(c) Cumulative Rights, Powers and Remedies. The rights, powers and remedies
given to the Secured Parties by this Agreement shall be in addition to all
rights, powers and remedies given the Secured Parties by virtue of any statute
or rule of law.

(d) Waiver. Any forbearance, failure, or delay by the Secured Parties in
exercising any right, power or remedy under this Agreement shall not be deemed
to be a

 

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waiver of such right, power or remedy, and any single or partial exercise of any
right, power or remedy, under this Agreement shall not preclude the further
exercise thereof; and every right, power and remedy of the Secured Parties shall
continue in full force and effect until such right, power or remedy is
specifically waived by an instrument in writing executed by the Collateral
Agent.

(e) Binding Effect. All of the terms, covenants, warranties and representations
contained herein shall be binding upon the parties, their heirs, successors and
assigns.

(f) Entire Agreement. This Agreement, the Notes, the Purchase Agreement and the
other Transaction Documents entered into by and between the parties hereto and
thereto constitute the entire agreement between the parties with respect to the
subject matter of this Agreement, and supersede all agreements, representations,
warranties, statements, promises and understandings not specifically set forth
herein or therein. No party hereto has in any way relied, nor shall in any way
rely, upon any oral or written agreements, representations, warranties,
statements, promises or understandings not specifically set forth herein.

(g) Amendments. Neither this Agreement nor any term hereof may be changed,
waived, discharged or terminated orally, but only by an instrument in writing
signed by the Pledgor and the Collateral Agent.

(h) Headings. The headings in this Agreement are for purposes of reference only
and shall not limit or otherwise affect the meaning hereof.

(i) Further Assurances. The parties hereto agree that they shall sign such
additional and supplemental documents to implement the transactions contemplated
pursuant to this Agreement when requested to do so by any party to this
Agreement.

(j) Counterparts. This Agreement may be executed in counterparts, each of which
shall be regarded as the original and all of which shall constitute one and the
same Agreement.

13. Representations, Warranties and Covenants of Pledgor. The Pledgor
represents, warrants and covenants to the Secured Parties as follows:

(a) Pledgor is the record and beneficial owner of, and has good and marketable
title to, the Shares pledged hereunder, free of any and all liens, charges,
encumbrances and security interests of every kind and nature (other than the
lien created by this Agreement);

(b) Pledgor has good right and legal authority to pledge the Shares owned by it
in the manner hereby done or contemplated;

(c) No authorization, approval, or other action by, and no notice to or filing
with, any third party, governmental authority or regulatory body is required for
the validity of the pledge by Pledgor of the Shares pursuant to this Agreement
or for the execution, delivery or performance of this Agreement by Pledgor;

 

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(d) This Agreement constitutes the legal, valid and binding obligation of
Pledgor and the pledge effected hereby is effective to vest in the Secured
Parties their rights in the Shares as set forth herein.

All representations, warranties and covenants made by Pledgor contained in this
Agreement shall survive the execution, delivery and performance of this
Agreement until the termination of this Agreement.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
date first written above.

 

NEXXUS LIGHTING, INC. By:   /s/ John C. Oakley Name:   John C. Oakley Title:  
Chief Financial Officer COLLATERAL AGENT: /s/ Jay Weil Name: Jay Weil

 

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