Question 3.1: In Chapter 2, we learned that approximately 30 billion nucle......

Introduction to Nuclear Reactor Physics [1368692]

In Chapter 2, we learned that approximately 30 billion nuclear fissions are required every second to produce one watt of thermal power. Using this information, estimate how many fissions are required per second to produce 3000 MW of thermal energy from a thermal water reactor.

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We know that 3000 MW of thermal power requires 3,000,000,000 as many neutrons as it does to produce 1 watt of thermal power. Therefore, the number of neutrons required to produce 1000 MW of electricity per second (or 3000 MW of thermal power) is $3,000,000,000 × 30,000,000,000 = 9 × 10^{19}$ fission neutrons per second. This is 90 billion billion nuclear fissions every second.

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