The United States has climbed in the rankings of the world’s most energy secure countries, according to a ranking compiled by the U.S. Chamber of Commerce Institute for 21st Century Energy.

In the new edition of the institute’s “International Index of Energy Security Risk,” Norway takes the top spot, while the United States ranks sixth and Ukraine receives the lowest scores among the top 25 energy users ranked on 29 metrics covering the years 1980-2012.

“The United States showed improvement in our rankings as a result of greater energy self reliance propelled by increased unconventional oil and gas output,” said institute CEO Karen Harbert. “Combined with growing energy production from Canada and a reformed hydrocarbon sector in Mexico, it’s possible we’ll soon see the world’s energy center of gravity shifting away from the Middle East and towards North America, bringing with it even greater economic and geopolitical advantages.”

This year’s index is the latest in the institute’s series that provides a qualitative analysis of energy security. The institute also produces the “Index of U.S. Energy Security Risk,” which in 2013 also showed improvement for the United States as a result of unconventional oil and gas production.

Norway’s first place finish is driven by a strong natural resource base, which makes it a net exporter of fossil fuels. Norway is one of the world’s largest natural gas exporters and also exports oil and coal. Rounding out the top five are Mexico, New Zealand, United Kingdom and Canada.

At the other end of the spectrum, Ukraine has consistently ranked last among the top 25 energy users. Ukraine must import virtually all forms of energy and is especially reliant on Russia for natural gas. Its economy is also very energy inefficient, the institute said. While the rankings do not reflect the latest unrest in Ukraine, concerns about supply disruption contributed to its low ranking.

“The 2013 International Index notes that Ukraine has realized its energy vulnerability and has been taking steps to become more self-reliant by investing in expanded oil and gas exploration and production, diversifying supply sources, and privatizing its coal-mining sector,” said Steve Eule, institute vice president. “Unfortunately, these investments are still years away from producing results, which leaves Ukraine especially vulnerable during a crisis.”

In 2013, the United States ranked sixth, up one spot from last year. While all nations in the index saw a decrease in risk from much lower price volatility in 2012, the United States benefited from an 835,000 b/d increase in production, most of which was from unconventional sources of energy. Electricity source diversity is also a relative strength for the United States. Affordable energy is another key U.S. advantage, especially in comparison to countries in Western Europe, which have some of the highest energy prices in the world.