| 2000 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Total Single Detached Heating System Stock (thousands) | 2,521.4 | 2,930.1 | 2,950.3 | 2,970.2 | 2,987.5 | 3,008.1 | 3,033.5 | 3,073.6 | 3,121.4 | 3,172.9 | 3,224.4 | |
Heating System Stock by Heating System Type (thousands) | ||||||||||||
| Heating Oil – Normal Efficiency | 58.8 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
| Heating Oil – Medium Efficiency | 113.4 | 123.8 | 120.0 | 113.7 | 106.9 | 99.5 | 91.6 | 83.3 | 74.7 | 65.8 | 57.3 | |
| Heating Oil – High Efficiency | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
| Natural Gas – Normal Efficiency | 735.2 | 42.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
| Natural Gas – Medium Efficiency | 482.5 | 651.9 | 633.3 | 602.5 | 568.2 | 531.2 | 492.0 | 452.0 | 413.4 | 376.0 | 340.2 | |
| Natural Gas – High Efficiency | 391.4 | 1,149.9 | 1,212.8 | 1,258.3 | 1,303.6 | 1,351.1 | 1,403.1 | 1,464.5 | 1,533.1 | 1,603.0 | 1,670.1 | |
| Electric | 337.2 | 389.1 | 396.5 | 398.9 | 401.9 | 406.3 | 410.9 | 417.0 | 423.6 | 430.5 | 436.9 | |
| Heat Pump | 160.3 | 265.4 | 273.0 | 277.5 | 282.2 | 288.4 | 295.5 | 305.2 | 316.6 | 328.6 | 341.3 | |
| Other1 | 31.7 | 54.2 | 59.0 | 63.5 | 68.4 | 74.1 | 81.0 | 89.5 | 94.3 | 99.6 | 105.4 | |
| Wood | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
Dual Systems | ||||||||||||
| Wood/Electric | 97.2 | 114.1 | 115.2 | 115.0 | 115.1 | 115.5 | 116.2 | 117.3 | 118.7 | 120.2 | 121.8 | |
| Wood/Heating Oil | 87.0 | 102.4 | 103.4 | 103.3 | 103.3 | 103.7 | 104.4 | 105.4 | 106.7 | 108.1 | 109.5 | |
| Natural Gas/Electric | 16.4 | 22.5 | 22.9 | 23.1 | 23.3 | 23.6 | 24.0 | 24.4 | 24.9 | 25.4 | 25.9 | |
| Heating Oil/Electric | 10.3 | 14.0 | 14.2 | 14.3 | 14.5 | 14.6 | 14.9 | 15.1 | 15.4 | 15.7 | 16.0 | |
Shares (%) | ||||||||||||
| Heating Oil – Normal Efficiency | 2.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
| Heating Oil – Medium Efficiency | 4.5 | 4.2 | 4.1 | 3.8 | 3.6 | 3.3 | 3.0 | 2.7 | 2.4 | 2.1 | 1.8 | |
| Heating Oil – High Efficiency | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
| Natural Gas – Normal Efficiency | 29.2 | 1.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
| Natural Gas – Medium Efficiency | 19.1 | 22.2 | 21.5 | 20.3 | 19.0 | 17.7 | 16.2 | 14.7 | 13.2 | 11.9 | 10.5 | |
| Natural Gas – High Efficiency | 15.5 | 39.2 | 41.1 | 42.4 | 43.6 | 44.9 | 46.3 | 47.6 | 49.1 | 50.5 | 51.8 | |
| Electric | 13.4 | 13.3 | 13.4 | 13.4 | 13.5 | 13.5 | 13.5 | 13.6 | 13.6 | 13.6 | 13.6 | |
| Heat Pump | 6.4 | 9.1 | 9.3 | 9.3 | 9.4 | 9.6 | 9.7 | 9.9 | 10.1 | 10.4 | 10.6 | |
| Other1 | 1.3 | 1.8 | 2.0 | 2.1 | 2.3 | 2.5 | 2.7 | 2.9 | 3.0 | 3.1 | 3.3 | |
| Wood | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
Dual Systems | ||||||||||||
| Wood/Electric | 3.9 | 3.9 | 3.9 | 3.9 | 3.9 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | |
| Wood/Heating Oil | 3.4 | 3.5 | 3.5 | 3.5 | 3.5 | 3.4 | 3.4 | 3.4 | 3.4 | 3.4 | 3.4 | |
| Natural Gas/Electric | 0.6 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | |
| Heating Oil/Electric | 0.4 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | |