| Rank | No Fuel Used Heating House Percentage ▼ | School District / Population |
| 1. | 1.7% | Essex School District / 6,682 |
| 2. | 1.6% | Eastford School District / 1,690 |
| 3. | 1.4% | Middletown School District / 47,530 |
| 4. | 1.0% | Madison School District / 18,264 |
| 5. | 0.9% | Regional High School District 04 / 15,408 |
| 6. | 0.8% | Portland School District / 9,500 |
| 7. | 0.8% | Andover School District / 3,185 |
| 8. | 0.8% | Cromwell School District / 14,059 |
| 9. | 0.7% | Regional School District 13 / 11,794 |
| 10. | 0.7% | Hartford School District / 124,879 |
| 11. | 0.6% | Clinton School District / 13,259 |
| 12. | 0.6% | Litchfield School District / 8,454 |
| 12. | 0.6% | Regional School District 18 / 9,959 |
| 12. | 0.6% | Voluntown School District / 2,599 |
| 15. | 0.6% | New Haven School District / 129,898 |
| 15. | 0.6% | Westbrook School District / 6,928 |
| 17. | 0.5% | Norwich School District / 40,322 |
| 18. | 0.5% | East Hartford School District / 51,171 |
| 18. | 0.5% | Lebanon School District / 7,289 |
| 20. | 0.5% | Hartland School District / 2,198 |
| 21. | 0.5% | Hebron School District / 9,649 |
| 22. | 0.5% | Columbia School District / 5,464 |
| 22. | 0.5% | Rocky Hill School District / 19,631 |
| 22. | 0.5% | Deep River School District / 4,636 |
| 25. | 0.5% | Ridgefield School District / 24,648 |
| 26. | 0.4% | Killingly School District / 17,345 |
| 27. | 0.4% | Granby School District / 11,243 |
| 28. | 0.4% | East Hampton School District / 12,953 |
| 29. | 0.4% | Regional High School District 08 / 19,216 |
| 30. | 0.4% | Old Saybrook School District / 10,268 |
| 30. | 0.4% | West Hartford School District / 63,157 |
| 32. | 0.4% | Derby School District / 12,858 |
| 33. | 0.3% | Weston School District / 10,203 |
| 34. | 0.3% | Hamden School District / 60,735 |
| 34. | 0.3% | Seymour School District / 16,487 |
| 36. | 0.3% | Putnam School District / 9,562 |
| 37. | 0.3% | Winchester School District / 11,189 |
| 38. | 0.3% | Pomfret School District / 4,231 |
| 38. | 0.3% | Bridgeport School District / 144,446 |
| 38. | 0.3% | Waterbury School District / 110,074 |
| 41. | 0.2% | Groton School District / 40,079 |
| 42. | 0.2% | Meriden School District / 60,674 |
| 43. | 0.2% | Manchester School District / 58,078 |
| 44. | 0.2% | East Haven School District / 29,188 |
| 44. | 0.2% | Stamford School District / 122,878 |
| 46. | 0.2% | Wilton School District / 18,201 |
| 47. | 0.2% | West Haven School District / 55,386 |
| 48. | 0.2% | East Lyme School District / 19,168 |
| 49. | 0.2% | Name N/A / 217,821 |
| 49. | 0.2% | Torrington School District / 36,239 |
| 49. | 0.2% | Enfield School District / 44,699 |
| 49. | 0.2% | Shelton School District / 39,641 |
| 53. | 0.1% | Farmington School District / 25,329 |
| 54. | 0.1% | Wethersfield School District / 26,670 |
| 54. | 0.1% | Cheshire School District / 29,253 |
| 54. | 0.1% | Norwalk School District / 85,853 |
| 57. | 0.1% | Regional School District 16 / 15,465 |
| 58. | 0.1% | Westport School District / 26,516 |
| 58. | 0.1% | Danbury School District / 81,057 |
| 58. | 0.1% | Bristol School District / 60,502 |
| 61. | 0.1% | Regional School District 12 / 7,600 |
| 61. | 0.1% | Greenwich School District / 61,428 |
| 63. | 0.1% | Stonington School District / 18,528 |
| 64. | 0.1% | Wallingford School District / 45,047 |
| 64. | 0.1% | Trumbull School District / 36,008 |
| 66. | 0.1% | Stratford School District / 51,440 |
| 66. | 0.1% | New Milford School District / 28,067 |
| 66. | 0.1% | Branford School District / 28,062 |
| 69. | 0.1% | Newington School District / 30,520 |
| 70. | 0.0% | New Britain School District / 73,122 |
Please note that we only rank locations with 'No Fuel Used Heating House Percentage' data. The rank above might not be a complete list. Locations without 'No Fuel Used Heating House Percentage' data are not listed.
*ACS stands for U.S. Census American Community Survey. According to the U.S. Census, if the date is a range, you can interpret the data as an average of the period of time.
