Residential Sector
Atlantic
Table 27: Cooling System Stock by Type, New Unit Efficiencies, Stock Efficiencies and Unit Capacity Ratio
  1990   2011 2012 2013 2014 2015
Total Cooling System Stock (thousands) 32.6   229.9 256.6 287.1 326.4 371.6

System Stock by Type (thousands)
Room 23.4   160.5 175.9 193.1 216.9 243.7
Central 9.2   69.4 80.7 94.0 109.5 127.9

Shares (%)
Room 71.7   69.8 68.5 67.3 66.4 65.6
Central 28.3   30.2 31.5 32.7 33.6 34.4

New Unit Efficiencies
Room (EER)1 7.1   12.0 12.0 12.0 12.0 12.0
Central (SEER)2 9.1   13.0 13.0 13.0 13.0 13.0

Stock Efficiencies
Room (EER)1 6.8   10.6 10.8 11.0 11.2 11.3
Central (SEER)2 8.6   11.2 11.4 11.6 11.7 11.9

Unit Capacity Ratio (Btu/hour)
Room 10,114   9,103 9,108 9,113 9,120 9,126
Central 32,356   33,271 33,278 33,284 33,290 33,303

Footnotes:

1) Energy Efficiency Ratio.
2) Seasonal Energy Efficiency Ratio.