Niagara Falls
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< p>The nominal lifespan of thermal power plants is generally 40 years. As the useful life approaches, the reliability and efficiency of power plants decline rapidly. According to data provided by the North American Reliability Association, after 40 years of operation of 50 to 200 Mw units, the shutdown rate in the event of an accident will reach approximately 20%. Continuing operation is considered dangerous and uneconomical, and new units must be replaced.