In January 2016, the Company repurchased $41.0 million principal amount of the Senior Notes pursuant to its open market repurchase program, resulting in total repurchases of $49.6 million principal amount of the Senior Notes under that program. On September 8, 2016, the Company repaid the $135.0 million outstanding under the Revolver.
Off-Balance Sheet Arrangements
As of December 31, 2015, the Company had one outstanding $0.5 million letter of credit issued under the terms of the Revolver, which was issued in support of the Alto Cielo acquisition.
Critical Accounting Policies and Estimates
The preparation of financial statements in conformity with accounting principles generally accepted in the U.S. requires us to make estimates and assumptions in certain circumstances that affect amounts reported in the accompanying consolidated financial statements and related footnotes. In preparing these financial statements, management has made its best estimates of certain amounts included in the financial statements. Application of these accounting policies and estimates, however, involves the exercise of judgment and use of assumptions as to future uncertainties and, as a result, actual results could differ from these estimates. In arriving at our critical accounting estimates, factors considered were how accurate the estimate or assumptions have been in the past, how much the estimate or assumptions have changed and how reasonably likely such change may have a material impact. Our critical accounting policies and estimates are more fully described in Item 15. Note 2 - Summary of Significant Accounting Policies to the Company’s financial statements and notes thereto as of December 31, 2015 and 2014 and for the years ended December 31, 2015, 2014 and 2013, included in Item 15. Financial Statements and Exhibits. There have been no significant changes to our critical accounting policies and estimates since December 31, 2015. Our critical accounting policies are discussed below.
Restricted cash consists of cash on deposit in financial institutions that is restricted to satisfy the requirements of certain debt and acquisition agreements and funds held within the Company's project companies that are restricted for current debt service payments and other purposes in accordance with the applicable debt agreements. These restrictions include: (i) cash on deposit in collateral accounts, debt service reserve accounts, and maintenance reserve accounts; and (ii) cash on deposit in operating accounts but subject to distribution restrictions due to debt defaults as of the balance sheet date.
Cash Committed for Construction Projects
Cash committed for construction projects includes loan proceeds deposited into bank accounts in the normal course of business for general use only in the operations of the project company to build power plants. The loan proceeds cannot be used by other project companies or for general corporate purposes and is therefore considered restricted. In certain instances, withdrawal of such funds may only occur after certain milestones are met or expenditures during construction have been incurred and approved by the lender in accordance with the terms of the debt agreement. Approvals for the disbursement of such funds are typically received based on support for the qualified expenditures related to the projects provided there are no conditions of default under the loans.
Viability Gap Funding Subsidies
Four of our solar power plants in India (NSM Suryalabh, NSM Sitara, NSM L'Volta and Focal) are entitled to receive viability gap funding support in an amount determined through a competitive bidding process. The viability gap funding support is funded by India’s National Clean Energy Fund and is paid by the offtake counterparty to these solar power plants, the Solar Energy Corporation of India (“SECI”), a not-for-profit company established by the Ministry of New and Renewable Energy to facilitate solar energy generation capacity in India. The program is expected to provide viability gap funding subsidies to the applicable four solar power plants in the aggregate amount of INR 1,189.4 million, 50% of which is payable as early as three months after each power plant's commissioning, and 10% of which is payable each year for five years thereafter, subject to the plant meeting certain requirements. SECI is contractually obligated to establish an irrevocable letter of credit to secure its payment obligations under the PPA. Additionally, SECI is required to hypothecate the revenues it receives under its back-to-back power sale agreement with local utilities to the project.
The Company recorded the awarded viability gap funding in full as a reduction to the cost of power plants in service, with a $10.7 million receivable included in current other assets, and $7.1 million included in other assets in the consolidated balance sheet as of December 31, 2015. The current portion of the viability gap funding includes the initial 50.0% receivable following the solar power plant’s commercial operation date and the 10.0% receivable in first year thereafter. The initial 50.0%