UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549



FORM 10-Q/A

(Amendment No.1)



QUARTERLY REPORT PURSUANT TO SECTION 13
OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934



For the quarterly period ended September
30, 2015



Commission file number: 0-19771



ACORN ENERGY, INC.

(Exact name of registrant as specified in
charter)



|Delaware
        (State or other jurisdiction ofincorporation or organization)           |  | 22-2786081
        (I.R.S. EmployerIdentification No.)
|---------------------------------------------------------------------------------------- |  | ------------------------------------------------------
|                                                                                         |  |                                                       
|3844 Kennett Pike, Wilmington, Delaware
        (Address of principal executive offices) |  | 19807
        (Zip Code)                              



302-656-1707

(Registrant’s telephone number,
including area code)



Indicate by check mark whether the registrant (1) has filed
all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or
for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements
for the past 90 days. Yes x No  ̈



Indicate
by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive
Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such
shorter period that the registrant was required to submit and post such files).Yes x No  ̈



Indicate by check mark whether the registrant
is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions
of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2
of the Exchange Act. (Check one):



|Large accelerated filer  ̈ | Accelerated filer  ̈ | Non-accelerated filer  ̈ | Smaller reporting company x
|------------------------- | ------------------- | ----------------------- | ---------------------------



Indicate
by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).Yes  ̈ No x



Indicate the number of shares outstanding
of each of the issuer’s classes of common stock, as of the latest practicable date.



|Class                                   |  | Outstanding at November 16, 2015
|--------------------------------------- |  | --------------------------------
|Common Stock, $0.01 par value per share |  | 27,325,591                      











EXPLANATORY NOTE



Acorn Energy, Inc. is filing this Amendment
No. 1 (this “Form 10-Q/A”) to our Quarterly Report on Form 10-Q for the quarter ended September 30, 2015 (the “Form
10-Q”), filed with the U.S. Securities and Exchange Commission (“SEC”) on November 16, 2015, for the sole purpose
of filing the exhibits 10.1 and 10.2 which were inadvertently not filed with the Form 10-Q.



No other changes have been made to the Form
10-Q. This Form 10-Q/A continues to speak as of the original filing date of the Form 10-Q, does not reflect events that may have
occurred subsequent to the original filing date, and does not modify or update any related disclosures made in the Form 10-Q.











PART II - OTHER INFORMATION



|ITEM 6. | EXHIBITS.
|------- | ---------



| | #10.1  | Loan and Security Agreement, dated as of August 13, 2015, by and between Acorn Energy, Inc., GridSense Inc., OMX Holdings Inc., OmniMetrix, LLC, Leap Tide Capital Partners III, LLC and the Guarantors as defined therein.                                                                                                                                                                                                                                                                                                                                                 
| | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| |        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
| | #10.2  | Intellectual Property Security Agreement, dated as of August 13, 2015, by and between Acorn Energy, Inc., GridSense Inc., OmniMetrix, LLC, and Leap Tide Capital Partners III, LLC.                                                                                                                                                                                                                                                                                                                                                                                         
| |        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
| | #31.1  | Certification of Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
| |        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
| | #31.2  | Certification of Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
| |        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
| | #32.1  | Certification of Chief Executive Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
| |        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
| | #32.2  | Certification of Chief Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
| |        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
| | *101.1 | The following financial statements from Acorn Energy’s Form 10-Q for the quarter ended September 30, 2015, filed on November 16, 2015, formatted in XBRL (eXtensible Business Reporting Language): (i) Condensed Consolidated Balance Sheets, (ii) Condensed Consolidated Statements of Operations, (iii) Condensed Consolidated Statements of Comprehensive Loss, (iv) Condensed Consolidated Statements of Changes in Equity, (v) Condensed Consolidated Statements of Cash Flows and (vi) Notes to Condensed Consolidated Financial Statements, tagged as blocks of text.
| |        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
| | #      | This exhibit is filed or furnished herewith.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
| | *      | This exhibit was previously filed or furnished.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             











SIGNATURES



Pursuant to the requirements
of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by its principal
financial officer thereunto duly authorized.



|                        | ACORN ENERGY, INC.
|----------------------- | ------------------
|                        |                   
|Dated: February 3, 2016 |                   
|                        |                   
|                        | By:               
|                        |                   
|                        |