A lot more Americans are staying cool during hot summer days than just 16 years ago. In 1993 68% of USA households had air conditioning. By 2009, 100 million homes or 87% did, according to the Energy Information Administration.
With air conditioning growth has often come a bigger home too. A bigger, air conditioned home over the last 50 years has been part of what rising incomes bought.
The last 10 years, however, have not seen rising real incomes for many Americans so the trend to bigger, air conditioned houses has likely run its course. In fact the real median national income has fallen since the credit crisis and near total economic collapse triggered by the Lehmann bankruptcy on September 15, 2008.
The increase in air conditioning usage from 1993 to 2009 is one reason why the nation's electricity usage during that period normally increased close to 2% every year. Rising temperatures, population growth, growing GDP, more work being done with electricity are still other explanations.
Air conditioning efficiency standards were also raised during this time and that moderated air conditioning demand and electricity bills.