this is the Economics Report.The political crisis in Ukraine has forced many European nationsto reconsider their dependence on Russia for energy.Some nations are looking at new ways to recover natural gas at home,these methods include a disputed processknown as hydraulic fracturing or fracking.The process involves the use of liquid chemicals to break rock.Experts believe Europe might have trillions of cubic meters of shale gas.Shale is a kind of rock.France, Poland and Ukraine are thoughtto have the largest amounts of shale gas.Large supplies have been found in Romania, Bulgaria and Britain.Lucia Seybert is with the the Wilson Center in Washington.She says the presence of large shale gas reservesand political problems in Ukrainehave increased interest in Europe's shale gas."With energy security it's not just a matter of supply,it's also a question of reliability.And one thing that this may do,it may expedite some of these explorations of shale gaswithin the European Union," Seybert said.But Europe is believed to be years away from major shale gas production.Poland, Britain and Romania are expected to start exploration by 2020.Removing shale gas through hydraulic frackingis the subject of often intense debate.Most drilling areas in Europe are near populated areasand environmental groups have raised concernsabout water and air pollution from fracking.There also are political concerns.Eric Stewart is the president of the Romanian-Americanand Polish-American Business Councils.He says European taxes and rules on the industrymake it difficult for gas removal companies.Energy companies also must battle a strong environmental movementand public opposition.Keith Smith is a former U.S. ambassador to Lithuania.He says the fracking can help Europe meet its energy needsif the plan includes fossil fuelsand renewable sources of energy like solar and wind.Much of Europe's gas flows through a pipelinefrom Russia across Ukraine.But Ukraine has had difficulty paying Russia's Gazprom energy company.And earlier this year,Ukrainian protesters ousted the country's pro-Russia president.The new government signed economic agreementswith the European Union, over Russian objections.Now Russia has signaled it may cut off gas to Ukraine, and to much of Europe.The Wilson Center's Lucia Seybert says shale gas explorationwill not provide Europe complete energy independence from Russian imports,but it will reduce that dependence in the long-term.And that's the Economics Report from VOA Learning English.