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|   | ACORN ENERGY, INC. |
|--------|--------------------|
|   |               |
|   | By:                |   |
|   |               | Joe B. Cogdell, Jr. |
|   |               | Vice President, General Counsel & Secretary |
|   |               |
|   | OPTIONEE:          |
|   |               |
|   | By:                |   |
|   |               | Samuel M. Zentman |

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| Date of grant                                 |   | March 27, 2006 |
|-----------------------------------------------|--------|----------------|
|                                          |   |           |
| Exercise price per share                      |   | $2.65          |
|                                          |   |           |
| Number of options originally granted          |   | 25,000         |
|                                          |   |           |
| Number of options currently held              |   |           |
|                                          |   |           |
| Number of options being exercised hereby      |   |           |
|                                          |   |           |
| In connection with this exercise [check one]: |   |           |

|                              |   | I enclose my check in the amount of $                                                                                                                                                                                                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|                                                                                                                                                                     |   |                                                                                                                                                                                                                                                                                                                                                                                                     |
|                              |   | I am delivering to a broker designated or approved by the Company irrevocable instructions to (i) sell shares of Common Stock acquired upon exercise and (ii) promptly deliver to the Company a portion of the proceeds thereof equal to the Exercise Price and any applicable withholding taxes.                                                                                                        |
|                                                                                                                                                                     |   |                                                                                                                                                                                                                                                                                                                                                                                                     |
|                                   |   | By my selection of this method of exercise, I hereby irrevocably direct the Company to effect this exercise by Net Exercise and reduce the number of shares of Common Stock issued upon this exercise by the smallest number of whole shares that has an aggregate Fair Market Value equal to or in excess of the aggregate exercise price for the Option Shares covered by the Exercise of this Option. |

| Optionee (Signature) |   | Social Security Number: |     |
|----------------------|--------|-------------------------|----------|
|                 |   |                    |     |
|                 |   |                    |     |
| Please print name    |   |                    |     |
|                 |   |                    |     |
| Date:                |   |                    | Address: |   |
|                 |   |                    |     |
|                 |   |                    |     |
|                 |   |                    |     |

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