Abstract: This invention fundamentally changes the basic design principles adopted over the last 50 years that addresses the basic root cause for the station blackout threat faced by all nuclear power plants. The Fukushima nuclear accident that occurred in Japan in 2011 could have turned benign had the plant implemented this invention. It uniquely utilizes the decay heat directly from the reactor core through steam cycles to produce useable power onsite with one or a number of steam turbines of less capacities in combination with compatible electric generators. Such arrangement is reliable to be the onsite energy source. The electric power produced by generators attached to these steam turbines could support necessary all safety functions. The result is that during the first week of urgent threat to the nuclear reactor, there will always be electric power available to run the safety equipment, computers, lighting and other vital devices continuously.