Regardless of where you stand on nuclear energy, you have to accept that it’s a thing in the U.S. Nuclear power accounted for 20.5 percent of electricity generated in the U.S. in April, the most recent month for which data is available from the U.S. Energy Information Administration.

Which state generates the largest amount of energy from nuclear sources? In April, it was Illinois, with nearly 7,864 thousand megawatt hours. Alaska, Colorado, Delaware, Hawaii, Idaho, Indiana, Kentucky, Maine, Montana, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, Rhode Island, South Dakota, Utah, Vermont, West Virginia and Wyoming don’t generate significant nuclear energy.

The following charts are based on a Green Energy Solutions analysis of the latest data from the EIA. Following are the states that generated the most electricity from nuclear in April (in thousand megawatt hours) and the percentage of total U.S. nuclear generation:

StateApr-19% of U.S. generation
Illinois7,86413.0
Pennsylvania6,16210.2
South Carolina4,8448.0
Texas3,2515.4
New York3,1035.1
Alabama3,0375.0
Georgia2,9034.8
Tennesee2,7314.5
Virginia2,3984.0
Florida2,2943.8

Across the country, electricity generation from nuclear power decreased 6.9 percent from March to April. Of the 29 states with significant nuclear generation, 21 recorded decreases during that period.

Following is a list of the states with significant nuclear energy generation, the amounts (in thousand megawatt hours) produced in March and February, and the percentage decrease (or increase) during that time:

StateAprilMarch% change
Alabama3,0372,9742.1
Arizona2,0632,967-30.5
Arkansas1,3331,365-2.3
California1,5521,13337.0
Connecticut7561,549-51.2
Florida2,2942,336-1.8
Georgia2,9031,85356.7
Illinois7,8648,187-3.9
Iowa376453-17.0
Kansas882912-3.3
Louisiana8458005.6
Maryland1,30398132.8
Massachusetts477492-3.0
Michigan2,2832,451-6.9
Minnesota9001,214-25.9
Mississippi9441,030-8.3
Nebraska572594-3.7
New Hampshire899927-3.0
New Jersey1,8402,360-22.0
New York3,1032,79611.0
North Carolina2,2622,874-21.3
Ohio1,32885854.8
Pennsylvania6,1627,179-14.2
South Carolina4,8444,999-3.1
Tennesee2,7313,481-21.5
Texas3,2513,721-12.6
Virginia2,3982,06716.0
Washington816861-5.2
Wisconsin570755-24.5
U.S.60,58165,080-6.9

How does the month compare with April 2018?

Nationally, nuclear generation increased 2.4 percent from April 2018 to April 2019. But some states saw significant differences year over year.

Generation fell by the greatest percentage in Connecticut, where it dropped 49.7 percent. Following are the 10 states that generated electricity from nuclear power in March in which the production of electricity from nuclear decreased by the greatest percentage:

StateApril 2019April 2018% change
Connecticut7561,504-49.7
Louisiana8451,556-45.7
Wisconsin570867-34.3
Minnesota9001,259-28.5
North Carolina2,2623,030-25.3
New Jersey1,8402,450-24.9
Ohio1,3281,579-15.9
Iowa376435-13.6
Florida2,2942,362-2.9
Washington816822-0.7

Generation increased by the greatest percentage in Mississippi; it went up 399.5 percent from April 2018. Following are the states in which the production of electricity from nuclear increased from year to year:

StateAprilMarch% change
Mississippi944189399.5
Massachusetts477114318.4
Arkansas1,33372284.6
Michigan2,2831,72932.0
Virginia2,3982,03118.1
South Carolina4,8444,13317.2
Texas3,2512,79116.5
Pennsylvania6,1625,51211.8
New York3,1032,8658.3
Alabama3,0372,8745.7

Which states get the highest percentage of electricity from nuclear?

The answer can change each month. In April, South Carolina topped the list, with New Hampshire second. Following are the 10 states that relied on nuclear energy for the largest percentage of their electricity generation.

State% from nuclearState% from nuclear
South Carolina61.9Pennsylvania39.7
New Hampshire61.7Virginia37.4
Illinois55.3Arkansas34.6
Tennessee48.9New Jersey33.6
Maryland44.2New York32.9