Although the percentage of energy-use attributed to buildings seems to vary depending on the news source, NREL released the 2013 edition of its annual Renewable Energy Data Book, which reports that US buildings represent 40 percent of total energy usage.
Other key findings from the report include:
Renewable electricity, including hydropower and biopower, grew to nearly 15 percent of total installed capacity and 13 percent of total electricity generation in the United States in 2013.
In 2013, renewable electricity accounted for more than 61 percent of all new electricity capacity installations in the United States.
In 2013 in the United States, solar electricity was the fastest growing electricity generation technology, with cumulative installed capacity increasing by nearly 66 percent from the previous year.
Renewable sources accounted for 23 percent of all electricity generation worldwide in 2013.