" For the entire EU, natural gas comprises about 25 percent of energy consumption. That means that Russian gas, at about 35 percent of total gas consumption, provides 9 percent of Europe’s overall energy. After Russia, the next largest source of gas is “indigenous” or “domestic supplies,” largely from the Groningen field in the Netherlands and the British sector of the North Sea. Norway, though not a member of the EU, is highly integrated with it economically, and supplies 24 percent of the EU’s gas; about 9 percent comes from North Africa, mainly Algeria. "
― Daniel Yergin , The New Map: Energy, Climate, and the Clash of Nations