Common Stock: During fiscal year 2016, 50 shares of common stock were granted from the 2011 Stock Compensation Plan (the “2011 Plan”) to the Company’s CEO and the corresponding fair value of $62 was included in share-based compensation. 85 shares of common stock were granted from the 2011 Plan to a contractor in lieu of professional services. 620 shares of common stock were granted and issued for entering into a convertible note agreement. During fiscal year 2015, stock options to purchase 13 shares of common stock were exercised that resulted in cash proceeds of $24 and had an intrinsic value of $10. In 2015, 100 shares of common stock were granted from the 2011 Plan to the Company's then CEO and the corresponding fair value of $114 was included in share-based compensation.

Stock options: The 2016 Plan authorizes the granting of awards in any of the following forms: (i) incentive stock options, (ii) nonqualified stock options, (iii) restricted stock awards, and (iv) restricted stock units, and expires on the earlier of October 28, 2026, or the date that all shares reserved under the 2016 Plan are issued or no longer available. The 2016 Plan provides for the issuance of up to 2,000 shares of common stock pursuant to awards granted under the 2016 Plan. Options granted to employees typically vest over two years, while grants to non-employee directors vest in six months. As of December 31, 2016, 20 options were outstanding under the 2016 Plan. Our 2011 Plan authorizes the granting of awards in any of the following forms: (i) stock options, (ii) stock appreciation rights, and (iii) other share-based awards, including but not limited to, restricted stock, restricted stock units or performance shares, and expires on the earlier of May 12, 2021, or the date that all shares reserved under the 2011 Plan are issued or no longer available. Options granted to employees typically vest over two years, while grants to non-employee directors vest in six months. As of December 31, 2016, 485 options were outstanding under the 2011 Plan. No additional awards will be granted under the 2011 Plan after the adoption of the 2016 Plan. Our 2006 Stock Option Plan (the “2006 Plan”) expired on June 30, 2011, but the options outstanding under the 2006 Plan continue to be exercisable in accordance with their terms. As of December 31, 2016, 206 options were outstanding to employees and non-employee directors under the 2006 Plan. We issue new common stock when stock options are exercised. The Company periodically grants stock options that vest based upon the achievement of performance targets. For performance based options, the Company evaluates the likelihood of the targets being met and records the expense over the probable vesting period.

The fair value of each option grant is estimated on the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions for fiscal years 2016 and 2015:

Additional information relating to all outstanding options is as follows (in thousands, except per share data):

The weighted average fair value per option of options granted during fiscal years 2016 and 2015 was $0.88 and $1.12, respectively. We recognized share-based compensation expense of $245 and $316 for fiscal years 2016 and 2015, respectively.  The aggregate intrinsic value in the preceding table represents the total pre-tax intrinsic value, based on our closing stock price of $1.12 on December 31, 2016, which theoretically could have been received by the option holders had all option holders exercised their options as of that date.  As of December 31, 2016, there were no in-the-money options exercisable.

Based on the value of options outstanding as of December 31, 2016, estimated future share-based compensation expense is as follows:

The estimate above does not include any expense for additional options that may be granted and vest during 2017.

Warrants:  On November 8, 2016, we issued a warrant to Energy Efficiency Investments, LLC (EEI) to purchase 167 shares of common stock at a price of $0.68 per share. The fair value of the warrant issued was $106 and it was exercisable in full at any time during a term of five years. The fair value per share of common stock underlying the warrant issued to EEI was $0.63 based on our closing stock price of $0.95. The exercise price may be reduced and the number of shares of common stock that may be purchased under the warrant may be increased if the Company issues or sells additional shares of common stock at a price lower than the then-current warrant exercise price or the then-current market price of the common stock. The shares underlying the warrant include legal restrictions regarding the transfer or sale of the shares. The fair value of the EEI warrant was recorded as deferred financing costs and is being amortized over the term of the commitment.

As of December 31, 2016, we had fully vested warrants outstanding to purchase 24 shares of common stock at a price of $3.55 per share and expire in May 2020 and 167 share of common stock at a price of $0.68 per share.

Preferred Stock: Our amended Articles of Incorporation authorize two million shares of preferred stock that may be issued from time to time in one or more series having such rights, powers, preferences and designations as the Board of Directors may determine. To date no such preferred shares have been issued.