When nuclear power plants are built, the Nuclear Regulatory Commission (NRC) has the authority to issue initial operating licenses for a period of 40 years. Beyond that, the reactors need license renewals, and the NRC has granted 20-year license renewals to 74 of the 100 operating reactors in the United States. These reactors may now operate for a total period of 60 years. They represent a cumulative capacity of a little more than 69,000 megawatts (MW). The NRC is currently reviewing license renewal applications for an additional 17 reactors, and expects to receive seven more applications in the next few years. With the bulk of the existing nuclear fleet licensed before 1990, nearly all existing reactors will be more than 60 years old by 2050. […]