Exelon’s (NYSE: EXC) nearly $8 billion bid for Constellation Energy (NYSE: CEG) on Thursday could stoke action in exchange traded funds (ETFs) that follow utilities and nuclear-energy stocks.

Exelon is the largest operator of U.S. nuclear power plants, and the deal would add stakes in five reactors in Maryland and New York, Bloomberg reported.

“The utility space has been an active one for mergers and acquisitions, as companies seek to cut costs and increase scale,” reports New York Times DealBook.

The resulting company will retain the Exelon name and be headquartered in Chicago, according to a press release.

“This merger creates the number one competitive energy provider with one of the industry’s cleanest and lowest-cost power generation fleets and one of the largest commercial, industrial and residential customer bases in the U.S.,” said Exelon Chairman and CEO John W. Rowe in a prepared statement.

Exelon is a top holding in Utilities HOLDRS (AMEX: UTH), Market Vectors Uranium + Nuclear Energy ETF (NYSEArca: NLR), Utilities Select Sector SPDR Fund (NYSEArca: XLU), Vanguard Utilities ETF (NYSEArca: VPU), iShares Dow Jones U.S. Utilities (NYSEArca: IDU), and iShares S&P Global Nuclear Energy Index (NYSEArca: NUCL).

Constellation shares were up more than 7% in premarket trading Thursday.

ETFs that invest in nuclear energy and uranium have fallen sharply amid Japan’s nuclear disaster. [Nuclear ETFs and the Japan Disaster.]