Nuclear Power in the USA

(Updated April 2013)

• The USA is the world's largest producer of nuclear power, accounting for more than 30% of worldwide nuclear generation of electricity.
• The country's 104 nuclear reactors produced 821 billion kWh in 2011, over 19% of total electrical output. There are now 103 units operable and three under construction.
• Following a 30-year period in which few new reactors were built, it is expected that 4-6 new units may come on line by 2020, the first of those resulting from 16 licence applications made since mid-2007 to build 24 new nuclear reactors.
• However, lower gas prices since 2009 have put the economic viability of some of these projects in doubt.
• Government policy changes since the late 1990s have helped pave the way for significant growth in nuclear capacity. Government and industry are working closely on expedited approval for construction and new plant designs.

In 2011, the US electricity generation was 4344 billion kWh gross, 1874 TWh (43%) of it from coal-fired plant, 1047 TWh (24%) from gas, 821 TWh (19%) nuclear, 351 TWh (8%) from hydro and 121 TWh (2.8%) from wind. Annual electricity demand is projected to increase to 5,000 billion kWh in 2030, though in the short term it is depressed and is not expected to recover to the 2007 level until about 2015. Annual per capita electricity consumption is currently around 12,300 kWh. Total capacity is 1041 GWe, less than one tenth of which is nuclear.

The USA has 103 nuclear power reactors in 31 states, operated by 30 different power companies. Since 2001 these plants have achieved an average capacity factor of over 90%, generating up to 807 billion kWh per year and accounting for 20% of total electricity generated. Capacity factor has risen from 50% in the early 1970s, to 70% in 1991, and it passed 90% in 2002, remaining at around this level since. The industry invests about $7.5 billion per year in maintenance and upgrades of these.

There are 68 pressurized water reactors (PWRs) with combined capacity of about 66 GWe and 35 boiling water reactors (BWRs) with combined capacity of about 34 GWe – for a total capacity of 101,355 MWe (see Nuclear Power in the USA Appendix 1: US Operating Nuclear Reactors). Almost all the US nuclear generating capacity comes from reactors built between 1967 and 1990. There have been no new construction starts since 1977, largely because for a number of years gas generation was considered more economically attractive and because construction schedules were frequently extended by opposition, compounded by heightened safety fears following the Three Mile Island accident in 1979. A further PWR – Watts Bar 2 – is expected to start up in 2015 following Tennessee Valley Authority's (TVA's) decision in 2007 to complete the construction of the unit.

Despite a near halt in new construction of more than 30 years, US reliance on nuclear power has continued to grow. In 1980, nuclear plants produced 251 billion kWh, accounting for 11% of the country's electricity generation. In 2008, that output had risen to 809 billion kWh and nearly 20% of electricity, providing more than 30% of the electricity generated from nuclear power worldwide. Much of the increase came from the 47 reactors, all approved for construction before 1977, that came on line in the late 1970s and 1980s, more than doubling US nuclear generation capacity. The US nuclear industry has also achieved remarkable gains in power plant utilisation through improved refuelling, maintenance and safety systems at existing plants.