About 51% of the generating capacity of the US is in plants that were at least 30 years old at the end of 2010. Most gas-fired capacity is less than 10 years old, while 73% of all coal-fired capacity is 30 years or older.7 Moreover, nationally, 70% of transmission lines and power transformers are 25 years or older, while 60% of circuit breakers are more than 30 years old.
