The Company and its subsidiaries have provided guarantees to certain of its institutional tax equity investors and financing parties in connection with its tax equity financing transactions. These guarantees do not guarantee the returns targeted by the tax equity investors or financing parties, but rather support any potential indemnity payments payable under the tax equity agreements, including related to management of tax partnerships and recapture of tax credits or renewable energy grants in connection with transfers of the Company’s direct or indirect ownership interests in the tax partnerships to entities that are not qualified to receive those tax benefits. The Company and its subsidiaries have also provided guarantees in connection with acquisitions of third party assets or to support project contractual obligations, including renewable energy credit sales agreements, and may provide additional guarantees in connection with future acquisitions or project contractual obligations. The Company and its subsidiaries have also provided other capped or limited contingent guarantees and other support obligations with respect to certain project-level indebtedness.
Commitments to Acquire Renewable Energy Facilities
As of December 31, 2016, the Company did not have any open commitments to acquire renewable energy facilities from SunEdison, other than as described with respect to the Invenergy Wind Option Agreements (see Note 20. Related Parties for further discussion).
The Company had a commitment of $58.7 million to acquire two wind power plants with a combined nameplate capacity of 98.6 MW from Invenergy Wind that expired on July 1, 2016. On January 20, 2017, Invenergy Wind provided notice of termination of the purchase agreement related to these power plants, and as a result, the Company does not expect to purchase these facilities.
The Company leases land and buildings under operating leases. Total rental expense was $23.5 million, $12.2 million and $1.0 million during the years ended December 31, 2016, 2015 and 2014, respectively. The following table summarizes the Company's future commitments under operating leases as of December 31, 2016:
The Company is not a party to any legal proceedings other than various administrative and regulatory proceedings arising in the ordinary course of the Company's business or as described below. While the Company cannot predict with certainty the ultimate resolution of such proceedings or other claims asserted against the Company, certain of the claims, if adversely concluded, could result in substantial damages or other relief.
Stockholder Derivative Lawsuits
On December 28, 2015, a verified stockholder derivative complaint (Central Laborers’ Pension Fund et al. v. Peter Blackmore et al., Case No. 11847) on behalf of the Company, was filed in the Court of Chancery in the State of Delaware against the Company, as nominal defendant, and SunEdison and certain individual directors of the Company, as defendants (the “Central Laborers’ Proceeding”). The lawsuit alleged that certain members of the Company’s Board breached their fiduciary duties of loyalty and care by agreeing to enter into an agreement (the “July Vivint Transaction”) with SunEdison on July 20, 2015 to acquire certain residential rooftop solar assets (the “Vivint Assets”) that SunEdison was acquiring as part of SunEdison’s acquisition of Vivint Solar, Inc. (“Vivint Solar”), by agreeing to terms that were grossly unfair to the Company and designed for the benefit of SunEdison, thereby failing to act in the best interests of the Company. The lawsuit further alleged that the approval of the modifications to the Company’s agreements under the July Vivint Transaction (the “December Vivint Transaction”) by the Board of the Company was on terms that were unfair to the Company and improperly favored SunEdison to the detriment of the Company and its stockholders. The complaint further alleged that SunEdison, as the Company’s controlling stockholder, breached its fiduciary duty not to advance SunEdison’s interest at the expense of the Company’s interests by causing the Company to (i) overpay to acquire assets in both the July Vivint Transaction and in the December