Karandikars & Associates

Nuclear Installed Capacity (GW)

Nuclear energy had a sad beginning, with August 1945 bombing of Hiroshima and Nagasaki during World War II

In December 1953, in his Atoms for Peace speech to the United Nations, President Eisenhower proposed joint international cooperation to develop peaceful applications of nuclear energy. He pledged the United States' determination "to help solve the fearful atomic dilemma--to devote its entire heart and mind to find the way by which the miraculous inventiveness of man shall not be dedicated to his death, but consecrated to his life"

The world's first commercial nuclear power station was opened in 1956 with an initial capacity of 50 MW per reactor, and a total of 200 MW

The 1973 oil crisis had a significant effect on countries such as France and Japan, which had relied more heavily on oil for electric generation (39% and 73% respectively) to invest in nuclear power

The period of 1970s to 1990 saw global installed nuclear capacity rising quickly. From less than 1 GW in 1960 and 18 GW in 1970, capacity rose to 133 GW in 1980 and 318 GW in 1990. The installed capacity was 350 GW in 2000

In the early 2000s, the nuclear industry was expecting a nuclear renaissance due to concerns about CO2 emissions. However the 2011 Fukushima accident again changed the perception about future of nuclear power. Following the Tohoku earthquake on 11 March 2011, one of the largest earthquakes ever recorded, and a subsequent tsunami off the coast of Japan, the Fukushima Daiichi Nuclear Power Plant suffered three core meltdowns due to failure of the emergency cooling system for lack of electricity supply. This resulted in the most serious nuclear accident since the Chernobyl disaster

The Fukushima Daiichi nuclear accident prompted a re-examination of nuclear safety and nuclear energy policy in many countries. Germany approved plans to close all its reactors by 2022. Many other countries reviewed their nuclear power programs. Germany closed its last plants in 2023 and Taiwan in 2025. Belgium, Spain, Switzerland, UK have their respective nuclear reactors decommissioning / phaseout targets

Nonetheless, many commentators consider outlook for nuclear power as positive, with global capacity potentially doubling by 2050, driven by a need for reliable, low-carbon energy and supported by technological advancements like small modular reactors (SMRs)

As at 2023, World installed nuclear capacity was 382.4 GW, that of China was 54.2 GW, that of India was 6.9 GW, while that of US was 95.7 GW. France had 61.4 GW capacity

Japan's nuclear capacity peaked at 47.6 GW during 2005-06. After Fukushima, all the plants were shut down one by one, and hence reported capacity was nil in 2014. Japan has progressively restarted its nuclear plants, and as at 2023, its capacity was 15.9 GW

Our section Electricity from Nuclear as a percent of total covers country-wise share of Nuclear in total electricity generation

View the trends graphically

Types of Nuclear Reactors:

The IAEA classifies nuclear reactors by coolant and moderator, with major types including Pressurized Water Reactors (PWRs), Boiling Water Reactors (BWRs), Pressurized Heavy Water Reactors (PHWRs), Light Water Graphite Reactors (LWGRs), and Gas-Cooled Reactors (GCRs), alongside emerging advanced reactors like Small Modular Reactors (SMRs), Fast Reactors (FBRs), and Molten Salt Reactors (MSRs)

PWR (Pressurized Light-Water-Cooled and Moderated Reactor): The most common type, using light water for cooling and moderation (e.g., in USA, France)

BWR (Boiling Light-Water-Cooled and Moderated Reactor): Also uses light water but allows boiling within the reactor core (e.g., in USA, Japan)

PHWR (Pressurized Heavy-Water Moderated and Cooled Reactor): Uses heavy water, common in Canada (CANDU) and India (e.g., PHWRs)

LWGR (Light-Water-Cooled, Graphite Moderated Reactor): A Russian design (e.g., RBMK)

GCR (Gas-Cooled, Graphite Moderated Reactor): Older UK designs like Magnox and AGR

Advanced & Emerging Types:

Fast Reactors (FBR/FR): Designed to produce more fissile material than they consume, often with liquid metal coolants

High-Temperature Gas-Cooled Reactors (HTGR): Use graphite moderator and gas coolant for very high temperatures

Molten Salt Reactors (MSRs): Use molten salts as coolant and sometimes fuel

Small Modular Reactors (SMRs): Smaller, factory-built reactors offering flexibility for various energy needs, including hybrid systems with renewables

Table below captures types of operational nuclear reactors along with their net electric power