The station supplies a quarter of Israel's electricity. It is widely felt that a direct rocket hit on the plant, and especially one with casualties, would lead to public demands for a military entry and operation in Gaza.
Approximately three Kassams have hit the area in or very close to the Rotenberg plant in recent weeks. One building was damaged.
The Ministry of Education recently issued a directive forbidding school trips to the power station and other sensitive installations north of Gaza - for reasons of Kassam-related threats.