COMMON STOCK PURCHASE AGREEMENT

TABLE OF CONTENTS

(continued)

TABLE OF CONTENTS

(continued)

This Common Stock Purchase Agreement (the “ Agreement ”) is made as of April 8, 2009 by and among CoaLogix Inc., a Delaware corporation (the “ Company ”), Acorn Energy, Inc., a Delaware corporation ( “Acorn ”), EnerTech Capital Partners III L.P., a Delaware limited partnership (“ EnerTech ”) and the persons who are designated as “Management Stockholders” on the signature pages to this Agreement (collectively, “ Management Stockholders ” and individually “ Management Stockholder ”).

A.            The Company, Acorn and EnerTech previously entered into that certain Common Stock Purchase Agreement dated as of February 29, 2008 pursuant to which EnerTech purchased 15,441 shares of the Company’s Common Stock, $0.001 par value per share (the “ Common Stock ”) at a price of $126.1566 per share, and that certain Common Stock Purchase Agreement dated as of May 13, 2008 pursuant to which Acorn purchased 12,464 shares of Common Stock and EnerTech purchased 2,200 shares of Common Stock at a price of $126.1566 per share.

B.            Acorn presently owns 85% of the issued and outstanding shares of Common Stock, and EnerTech presently owns 15% of the issued and outstanding shares of Common Stock.

C.            Acorn and EnerTech desire to purchase additional shares of Common Stock, and the Company desires to issue additional shares of Common Stock to Acorn and EnerTech on the terms as set forth herein below.  The Management Stockholders desire to purchase shares of Common Stock, and the Company desires to issue shares of Common Stock to the Management Stockholders on the terms as set forth herein below.

The parties hereby agree as follows:

1.            Purchase and Sale of Common Stock .

1.1.          Sale and Issuance of Common Stock .  Subject to the terms and conditions of this Agreement, Acorn, EnerTech and the Management Stockholders (hereinafter collectively referred to as the “ Purchasers ” or individually as a “ Purchaser ”) agree to purchase at the Closing and the Company agrees to sell and issue to Acorn, EnerTech and the Management Stockholders at each Closing (as hereinafter defined) that number of shares of the Company’s Common Stock set forth opposite Acorn’s, EnerTech’s and the Management Stockholders’ names on Exhibit A, pro rated for each Installment (as hereinafter defined) related to such Closing , at a purchase price of $7.20 per share, payable as set forth in Section 1.2(b) (the “ Purchase Price ”).  The shares of Common Stock issued to the Purchasers pursuant to this Agreement shall be referred to in this Agreement as the “ Shares .”

1.2.           Closing; Delivery .

(a)           The   closing of each purchase and sale of the Shares shall take place at 10:00 a.m., on the date on the business day on which the last of the conditions set forth in Sections 4 and 5 of this Agreement that are capable of being satisfied before each Closing are fulfilled or waived in accordance with this Agreement, at the offices of the Company, 11701 Mt. Holly Road, Charlotte, NC 28214 or at such other time and place as the Company, Acorn and EnerTech mutually agree upon, orally or in writing (which time and place are each designated as a “ Closing ”).

(b)           At each Closing, the Purchase Price will be funded by the Purchasers in installments (individually, an “Installment” and collectively, the “Installments”) in accordance with the schedule of Use of Proceeds as set forth in Section 6.3 and the terms of such Section.  The Purchasers covenant and agree that at each Closing they will fund and pay to the Company each Installment described in Section 6.3 within three business days of receiving from the Company a written request for funding (the “ Funding Notice ”) which satisfies the requirements for the applicable Installments set forth in Section 6.3 .  In connection with the Purchasers’ payment of any Installment, the Company shall promptly deliver to each of the Purchasers a certificate representing the Shares being purchased by each of the Purchasers at a particular Closing against payment of the respective Installment therefor by wire transfer to a bank account designated by the Company.

1.3.           Defined Terms Used in this Agreement .  In addition to the terms defined above, the following terms used in this Agreement shall be construed to have the meanings set forth or referenced below.

“ Affiliate ” means with respect to any person or entity (a “ Person ”) any Person which, directly or indirectly, controls, is controlled by, or is under common control with such Person, including, without limitation, any partner, officer, director, or member of such Person and any venture capital fund now or hereafter existing which is controlled by or under common control with one or more general partners or shares the same management company with such Person.

“ Code ” means the Internal Revenue Code of 1986, as amended.

“ Company Intellectual Property ” means all trademarks, service marks, tradenames, copyrights, trade secrets, licenses, information and proprietary rights and processes and all patents and patent rights owned or possessed by the Company.

“ EES Suit ” shall have the meaning given to it in Section 6.3 .

“ Evonik Suit ” shall have the meaning given to it in Section 6.3 .

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“ Funding Notice ” shall have the meaning given to it in Section 1.2(b) .

 “ Key Employee ” means any executive-level employee (including Vice President level positions) as well as any employee who either alone or in concert with others develops, invents, programs or designs any Company Intellectual Property.

“ Management Stockholders ” has the meaning assigned to it in the opening paragraph of the Agreement.

 “ Material Adverse Effect ” means a material adverse effect on the business, assets (including intangible assets), liabilities, financial condition, property, prospects   or results of operations of the Company or any of the SCR-Tech Entities.

“ Original Purchasers ” means Acorn and EnerTech.

 “ Purchasers ” has the meaning assigned to it in Section 1.1 .

“SCR-Tech Entities” means CoaLogix Tech inc. (formerly known as CESI-TECH Technologies, Inc.), CoaLogix Solutions Inc. (formerly known as CESI-SCR, Inc.), SCR-Tech LLC and MetalliFix LLC.

“ Securities Act ” means the Securities Act of 1933, as amended.

“ Shares ” has the meaning assigned to it in Section 1.1 .

“ Stockholders’ Agreement ” means that certain agreement by and among the Company and the Original Purchasers, dated as of February 29, 2008 and as amended and restated effective the date hereof.

“ Transaction Agreements ” means this Agreement, the Funding Notices and any other agreements, instruments or documents entered into in connection with this Agreement.

“ Use of Proceeds ”  means the amounts and uses of the Installments as set forth in the table  in Section 6.3 .

2.            Representations and Warranties of the Company .   The Company hereby represents and warrants to the Purchasers that, except as set forth on the Disclosure Schedule attached to this Agreement which exceptions shall be deemed to be part of the representations and warranties made hereunder, the following representations are true and complete as of the date hereof and will be true and correct as of the date of each Closing following any Funding Notice, except as otherwise indicated. The Disclosure Schedule shall be arranged in sections corresponding to the numbered and lettered sections and subsections contained in this Section 2 , and the disclosures in any section or subsection of the Disclosure Schedule shall qualify other sections and subsections in this Section 2 only to the extent it is readily apparent from a reading of the disclosure that such disclosure is applicable to such other sections and subsections.

For purposes of these representations and warranties, the phrase “to the Company’s knowledge” shall mean the knowledge after reasonable investigation of the Key Employees of the Company.

2.1.            Organization, Good Standing, Corporate Power and Qualification .  The Company is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware and has all requisite corporate power and authority to carry on its business as presently conducted and as proposed to be conducted.  The Company is duly qualified to transact business and is in good standing in each jurisdiction in which the failure to so qualify would have a Material Adverse Effect.

2.2.           Capitalization .  The authorized capital of the Company consists, immediately prior to the Closing (unless otherwise noted), of:

(a)           5,300,000   shares of Common Stock, 2,940,125 shares of which are issued and outstanding immediately prior to the Closing.  All of the outstanding shares of Common Stock have been duly authorized, are fully paid and nonassessable and were issued in compliance with all applicable federal and state securities laws.  The Company holds no treasury stock.

(b)            Section 2.2(c) of the Disclosure Schedule sets forth the options that the Company is committed to granting following the Closing.

(c)            Section 2.2(c) of the Disclosure Schedule sets forth the capitalization of the Company immediately following the Closing relating to the initial Installment including the number of shares of the following: (i) issued and outstanding Common Stock; (ii) the name of each holder of options for Common Stock, together with the number of shares for which such options are exercisable with respect to each holder, the applicable vesting schedule, if any, and the applicable exercise price; (iii) stock options not yet issued but reserved for issuance; and (iv) warrants or stock purchase rights, if any.  Except for (A) the rights provided in Sections 4 and 5 of the Stockholders’ Agreement, and (B) the securities and rights described in Section 2.2(b) of this Agreement and Section 2.2(c) of the Disclosure Schedule , there are no outstanding options, warrants, rights (including conversion or preemptive rights and rights of first refusal or similar rights) or agreements, orally or in writing, to purchase or acquire from the Company, or sell to the Company, any shares of Common Stock, or contracts, commitments, understandings, or arrangements by which the Company is or may become bound to issue Common Stock or any securities convertible into or exchangeable for shares of Common Stock.  Except as set forth on Section 2.2(c) of the Disclosure Schedule , no current or former shareholder of the Company's capital stock has, or with the giving of notice or any other actions may have, any appraisal rights or the right to obtain payment of the fair value of that shareholder's shares of Common Stock.  Except for as provided in the Stockholders’ Agreement, no shareholder of the Company or other person has any right to designate members to serve on the Company's board of directors or any committee thereof.

(d)           Except as set forth on Section 2.2(d) of the Disclosure Schedule , all outstanding shares of the Company’s Common Stock and all shares of the Company’s Common Stock underlying outstanding options are subject to a right of first refusal in favor of the Company upon any proposed transfer (other than transfers for estate planning purposes).  Except as set forth on Section 2.2(d) of the Disclosure Schedule , none of the Company’s stock purchase agreements or stock option documents contains a provision for acceleration of vesting (or lapse of a repurchase right) upon the occurrence of any event or combination of events. Except as set forth on Section 2.2(d) of the Disclosure Schedule , the Company has never adjusted or amended the exercise price of any stock options previously awarded, whether through amendment, cancellation, replacement grant, repricing, or any other means.

2.3.            Subsidiaries and Affiliates .  Except as set forth on Section 2.3 of the Disclosure Schedule , the Company does not own, directly or indirectly, any capital stock or other equity securities of any corporation or have any direct or indirect equity ownership in any business.

2.4.            Authorization .  All corporate action required to be taken by the Company’s Board of Directors and stockholders in order to authorize the Company to enter into the Transaction Agreements, and to issue the Shares at each Closing, has been taken or, in the case of the stockholders, will be taken prior to each Closing.  Subject to the terms of Sections 1.2(b) and 6.3 , all action on the part of the officers of the Company necessary for the execution and delivery of the Transaction Agreements, the performance of all obligations of the Company under the Transaction Agreements to be performed as of each Closing, and the issuance and delivery of the Shares has been taken or will be taken prior to each Closing.  The Transaction Agreements, when executed and delivered by the Company, shall constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their respective terms except (i) as limited by applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance, or other laws of general application relating to or affecting the enforcement of creditors’ rights generally, (ii) as limited by laws relating to the availability of specific performance, injunctive relief, or other equitable remedies, or (iii) to the extent the indemnification provisions contained in the Stockholders’ Agreement may be limited by applicable federal or state securities laws.

2.5.            Valid Issuance of Shares .  The Shares, when issued, sold and delivered in accordance with the terms and for the consideration set forth in this Agreement, will be validly issued, fully paid and nonassessable and free of restrictions on transfer other than restrictions on transfer under this Agreement, the Stockholders’ Agreement, applicable state and federal securities laws and liens or encumbrances created by or imposed by the Purchasers.  Assuming the accuracy of the representations of the Purchasers in Section 3 of this Agreement, the Shares will be issued in compliance with all applicable federal and state securities laws.

2.6.            Governmental Consents and Filings .  Assuming the accuracy of the representations made by the Purchasers in Section 3 of this Agreement, no consent, approval, order or authorization of, or registration, qualification, designation, declaration or filing with, any federal, state or local governmental authority is required on the part of the Company in connection with the consummation of the transactions contemplated by this Agreement, except for  filings, if any, pursuant to Regulation D of the Securities Act, and applicable state securities laws, which have been made or will be made in a timely manner.

2.7.            Litigation .  There is no claim, action, suit, proceeding, arbitration, complaint, charge or investigation pending or, to the Company’s knowledge, currently threatened that questions the validity of the Transaction Agreements or the right of the Company to enter into them, or to consummate the transactions contemplated by the Transaction Agreements.

2.8.            Compliance with Other Instruments .  The execution, delivery and performance of the Transaction Agreements and the consummation of the transactions contemplated by the Transaction Agreements will not result in any violation or be in conflict with or constitute, with or without the passage of time and giving of notice, either (i) a default under any instrument, judgment, order, writ, decree, contract or agreement to which the Company is a party or by which it is bound or (ii) an event which results in the creation of any lien, charge or encumbrance upon any property or assets of the Company or the suspension, revocation, forfeiture, or nonrenewal of any permit or license applicable to the Company.

2.9.           Rights of Registration and Voting Rights .  Except as provided in the Stockholders’ Agreement, the Company is not under any obligation to register under the Securities Act any of its currently outstanding securities or any securities issuable upon exercise or conversion of its currently outstanding securities.  Except as contemplated in the Stockholders’ Agreement, no stockholder of the Company has entered into any agreements with respect to the voting of capital shares of the Company.

2.10.         No Company Operations or Material Liabilities .  The Company is a holding company without operations other than the ownership of stock of its subsidiaries.  The Company, excluding its subsidiaries, has no material liabilities or obligations, contingent or otherwise, other than liabilities (i) under that certain Stock Purchase Agreement, dated November 7, 2007, by and among the Company, Acorn, Catalytica Energy Systems, Inc. and with respect to Article 11 thereof only, Renegy Holdings, Inc., (ii) under this Agreement and the Common Stock Purchase Agreements by and among the parties hereto dated February 29, 2008 and May 13, 2008, or (iii) as set forth on Section 2.10 of the Disclosure Schedule .

2.11.         Changes .  To the Company’s knowledge, since May 13, 2008, there has not been:

(a)           any change in the assets, liabilities, financial condition or operating results of the SCR-Tech Entities, except changes in the ordinary course of business that have not caused, in the aggregate, a Material Adverse Effect on the SCR-Tech Entities;

(b)           any damage, destruction or loss, whether or not covered by insurance, that would have a Material Adverse Effect on the SCR-Tech Entities;

(c)           any waiver or compromise by the Company of a valuable right or of a material debt owed to any of the SCR-Tech Entities;

(d)           any satisfaction or discharge of any lien, claim, or encumbrance or payment of any obligation by the Company, except in the ordinary course of business and the satisfaction or discharge of which would not have a Material Adverse Effect on the SCR-Tech Entities;

(e)           any material change to a material contract or agreement by which CoaLogix or the SCR-Tech Entities or any of their assets is bound or subject, except changes in the ordinary course of business that have not caused, in the aggregate, a Material Adverse Effect on the SCR-Tech entities;

(f)           any mortgage, pledge, transfer of a security interest in, or lien, created by the Company, with respect to any of the material properties or assets of the SCR-Tech Entities, except (i) liens for taxes not yet due or payable and liens that arise in the ordinary course of business and do not materially impair the Company’s or the SCR-Tech Entities’ ownership or use of such property or assets or (ii) as set forth on Section 2.11(f) of the Disclosure Schedule ;

(g)           any sale, assignment or transfer of any Company Intellectual Property   that could reasonably be expected to result in a Material Adverse Effect to the SCR-Tech Entities;

(h)           receipt of notice that there has been a loss of, or material order cancellation by, any major customer of any of the SCR-Tech Entities; or

(i)           except as set forth on Section 2.11(i) of the Disclosure Schedule , any other event or condition of any character, other than events affecting the economy or the Company’s industry generally, that could reasonably be expected to result in a Material Adverse Effect to the SCR-Tech Entities.

To the Company’s knowledge, since May 13, 2008 (x) the SCR-Tech Entities have carried on and operated their business in the ordinary course of business and (y) the SCR-Tech Entities have not suffered a Material Adverse Effect.

2.12.        Corporate Documents .  The Certificate of Incorporation, amendments thereto, and Bylaws of the Company are in the form provided to the Purchasers.  The copy of the minute books of the Company provided to the Purchasers contains minutes of all meetings of directors and stockholders and all actions by written consent without a meeting by the directors and stockholders since May 13, 2008 and accurately reflects in all material respects all actions by the directors (and any committee of directors) and stockholders with respect to all transactions referred to in such minutes.

2.13.        Offering .  Subject in part to the truth and accuracy of the Purchasers’ representations set forth in Article III of this Agreement, the offer, sale and issuance of the Shares as contemplated by this Agreement are exempt from the registration requirements of the Securities Act of 1933, as amended, and neither the Company nor any authorized agent acting on its behalf will take any action hereafter that would cause the loss of such exemption.

2.14.        Preemptive Rights .  The Company has fully satisfied (including with respect to rights of timely notification) or obtained enforceable waivers in respect of any preemptive or similar rights directly or indirectly affecting any of its securities.

2.15.        Consents .  All consents, approvals, releases, filings, terminations and waivers by third parties necessary to complete the transactions contemplated hereby that are set forth in Section 2.15 of the Disclosure Schedule have been obtained and delivered to the Purchasers and such consents, approvals, releases, filings, terminations and waivers have not expired or been withdrawn.

2.16.        Employment and Non-Competition Agreements .  William McMahon, Michael Mattes, Frank Wenz, Michael Cooper, Eric Dana and Joe Cogdell are bound by and have executed employment agreements with the Company and the SCR-Tech Entities, as applicable as well as joinder agreements to become parties to the Stockholders’ Agreement.  All other employees of the SCR-Tech Entities have entered into non-competition agreements with applicable SCR-Tech Entities.

2.17.       Qualified Business Stock .  The Shares when issued in accordance with the terms and conditions hereof, will be “Qualified Business Stock” as defined in Section 1202(c) of the Code for qualifying holders.

3.            Representations and Warranties of the Purchasers .  Each of the Purchasers hereby represents and warrants, individually and not jointly, to the Company that with respect to only itself:

3.1.          Authorization .  The Purchaser has full power, authority and capacity to enter into the Transaction Agreements.  The Transaction Agreements to which the Purchaser is a party, when executed and delivered by the Purchaser, will constitute valid and legally binding obligations of the Purchaser, enforceable in accordance with their terms, except (a) as limited by applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance, and any other laws of general application affecting enforcement of creditors’ rights generally, and as limited by laws relating to the availability of a specific performance, injunctive relief, or other equitable remedies, or (b) to the extent the indemnification provisions contained in the Stockholders’ Agreement may be limited by applicable federal or state securities laws.

3.2.          Compliance with Other Instruments .  The execution and delivery of this Agreement by the Purchaser, and the performance by the Purchaser of its obligations hereunder, will not conflict, or result in any violation of, or default under, any provision of any charter, bylaws, trust agreement, partnership agreement or other governing instrument applicable to the Purchaser, or any agreement or other instrument to which the Purchaser is a party or by which the Purchaser or any of the Purchaser’s properties are bound, or any permit, franchise, judgment, decree, order, rule or regulation applicable to the Purchaser or the Purchaser’s business or properties.

3.3.          Purchase Entirely for Own Account .  This Agreement is made with the Purchaser in reliance upon the Purchaser’s representation to the Company, which by the Purchaser’s execution of this Agreement, the Purchaser hereby confirms, that the Shares to be acquired by the Purchaser will be acquired for investment for the Purchaser’s own account, not as a nominee or agent, and not with a view to the resale or distribution of any part thereof, and that the Purchaser has no present intention of selling, granting any participation in, or otherwise distributing the same.  By executing this Agreement, the Purchaser further represents that the Purchaser does not presently have any contract, undertaking, agreement or arrangement with any person to sell, transfer or grant participations to such person or to any third person, with respect to any of the Shares. The Purchaser has not been formed for the specific purpose of acquiring the Shares.

3.4.          Disclosure of Information .  The Purchaser has had an opportunity to discuss the Company’s business, management, financial affairs and the terms and conditions of the offering of the Shares with the Company’s management. Except as set forth in the Transaction Agreements, no representations or warranties, whether written or oral, have been made to the Purchaser by the Company or any officer, employee, affiliate or agent of the Company.  The foregoing, however, does not limit or modify the representations and warranties of the Company in Section 2 of this Agreement or the right of the Purchaser to rely thereon.

3.5.          Restricted Securities .  The Purchaser understands that the Shares have not been, and will not be, registered under the Securities Act, by reason of a specific exemption from the registration provisions of the Securities Act which depends upon, among other things, the bona fide nature of the investment intent and the accuracy of the Purchaser’s representations as expressed herein.  The Purchaser understan