A. around 2014, Defendant B Co., Ltd. (hereinafter “Defendant B”) contracted Defendant C Co., Ltd. (hereinafter “Defendant C”) with the construction of the instant construction of the D-ground factory building (hereinafter “instant building”) in the former Sungsung-gun, Sungsung-gun (hereinafter “instant construction”).

B. On August 5, 2014, Defendant C subcontracted to the Plaintiff the instant construction work (hereinafter referred to as “instant construction work”) at KRW 60,000,00 for the completion of the relevant construction work.

C. On August 12, 2014, Defendant C subcontracted to the Plaintiff the instant construction of solar power generation facilities (hereinafter “instant solar power generation facilities”) at the scheduled date for completion of the instant construction works (hereinafter “instant subcontract”) at KRW 810,00,000, the construction cost was determined and subcontracted to the Plaintiff on September 30, 2014; and the said contract was finally changed to the scheduled date for completion of the instant construction works on December 30, 2014.

The Plaintiff completed the instant electrical construction and solar-powered construction; Defendant B obtained approval for the use of the instant building on October 10, 2014; and on April 20, 2015, concluded a PPA contract with the Korea Electric Power Corporation and started the commercial operation of solar power generation facilities (hereinafter “instant solar power plant”).

E. Meanwhile, the unit price for the manufacturer of solar power generation facilities to sell electricity to the Korea Electric Power Corporation is determined as “production weight x KW unit price x the Korea Power Exchange.” The weight of the instant solar power plant was determined as 1.038 according to the “Guidelines for Management and Operation of the Mandatory Supply System of New and Renewable Energy (wholly amended by the Ministry of Trade, Industry and Energy No. 2014-164, Sept. 16, 2014).”

F. On July 19, 2016, the Plaintiff and Defendant B settled the remainder of the construction cost of the instant electrical construction and solar-powered construction cost at KRW 245,50,00,000; Defendant B supplied the Plaintiff with a capt equivalent to KRW 63,835,200, and deducted it from the remainder of the construction cost; and solar energy.