America's Least and Most Reliable Power Grids, State by State

Every state's average reliability, computed the same way as every county page on this site: national percentile rank from 12 years of recorded DOE/ORNL outage data, not a survey or a single storm season. States below are ranked by their average county-level percentile (lower = less reliable) — only states with at least 5 graded counties in our dataset are included, since a 1-2 county sample isn't a meaningful state ranking.

Least reliable states, worst to best:

1. Maine — 7th percentile avg., 16 counties graded.

2. Puerto Rico — 9th percentile avg., 7 counties graded.

3. Louisiana — 10th percentile avg., 64 counties graded.

4. West Virginia — 12th percentile avg., 55 counties graded.

5. Florida — 22nd percentile avg., 67 counties graded.

6. New Hampshire — 24th percentile avg., 10 counties graded.

7. Michigan — 25th percentile avg., 82 counties graded.

8. Vermont — 26th percentile avg., 14 counties graded.

9. Connecticut — 27th percentile avg., 8 counties graded.

10. Arkansas — 33rd percentile avg., 75 counties graded.

Most reliable states, best to worst:

1. Nebraska — 84th percentile avg., 61 counties graded.

2. Arizona — 80th percentile avg., 15 counties graded.

3. Wyoming — 80th percentile avg., 22 counties graded.

4. Minnesota — 77th percentile avg., 85 counties graded.

5. South Dakota — 77th percentile avg., 65 counties graded.

6. North Dakota — 76th percentile avg., 52 counties graded.

7. New Mexico — 74th percentile avg., 28 counties graded.

8. Utah — 71st percentile avg., 28 counties graded.

9. Kansas — 70th percentile avg., 97 counties graded.

10. Colorado — 70th percentile avg., 53 counties graded.

State averages can hide a lot of county-level variation — a generally reliable state can still have a genuinely bad county, and vice versa. The individual worst and best counties nationally right now:

Worst counties nationally:

Clay County, West Virginia — 0th percentile nationally.

Lincoln County, West Virginia — 0th percentile nationally.

Cameron Parish, Louisiana — 0th percentile nationally.

Lafourche Parish, Louisiana — 0th percentile nationally.

Mayagüez Municipio, Puerto Rico — 0th percentile nationally.

Best counties nationally:

Clay County, South Dakota — 100th percentile nationally.

Clearwater County, Minnesota — 99th percentile nationally.

Limestone County, Alabama — 99th percentile nationally.

Valdez-Cordova, Alaska — 99th percentile nationally.

Brown County, Minnesota — 99th percentile nationally.

See our methodology page for exactly how the reliability grade and percentile are computed, and search any county directly on our homepage for its own specific history.