Energy Information Administration, the analytical arm of the energy department, said domestic oil production continued to set records.
EIA Administrator Adam Sieminski said crude oil imports have declined steadily since U.S. oil production passed the 12 million barrel per day mark in 2005.
"U.S. crude oil production increased to 7.5 million barrels per day in July, the highest output for any month since 1991," he said in a statement Tuesday. "EIA expects that U.S. monthly crude oil production will exceed U.S. crude oil imports as early as this October, the first time this will have happened since February 1995."
New drilling technologies means energy companies have better access to oil and natural gas reserves previously out of reach. EIA said it observed similar production gains in natural gas.
In terms of renewable energy, Sieminski said wind energy generation increased this year and is on pace to grow even further in 2014. Last week, the Energy Department awarded maritime acreage that would support the first large-scale offshore wind farm in the country.
The EIA said it expects "robust growth" in solar power generation, though it accounts for a small share of total U.S. power generation.