Renewable sources—geothermal and hydropower—provide effectively all of Iceland's electricity and around 85% of the nation's total primary energy consumption, with most of the remainder consisting of imported oil products used in transportation and in the fishing fleet. A 2000 report from the University of Iceland suggested that Iceland could potentially convert from oil to hydrogen power by 2040. Iceland's largest geothermal power plants are Hellisheiði and Nesjavellir, while Kárahnjúkar Hydropower Plant is the country's largest hydroelectric power station. When the Kárahnjúkavirkjun started operating, Iceland became the world's largest electricity producer per capita. Iceland is one of the few countries that have filling stations dispensing hydrogen fuel for cars powered by fuel cells. It is also one of a few countries capable of producing hydrogen in adequate quantities at a reasonable cost, because of Iceland's plentiful renewable sources of energy.