Princeton-based NRG Yield announced Thursday it has completed its acquisition of Energy Systems Company, based in Nebraska. Terms were not disclosed.

According to the announcement, NRG Yield, a wholly owned subsidiary of NRG Energy Inc., acquired the assets of privately held Energy Systems effective Thursday.

ESC is NRG Yield's first acquisition outside its relationship with parent company NRG Energy, and the ninth thermal generation project in its portfolio.

The company announced the acquisition in early Dec. 2013. It announced its first dividend in November.

Stay informed: Subscribe to free NJBIZ newsletters