The British government has been slow to make the major policy changes necessary to meet its stated goals of increasing renewable energy generation and combating global warming, a Parliamentary select committee said yesterday. The committee made a number of proposals to help move the country toward its target of producing 10 percent of its electricity from renewables by 2010, including a tax of about $4.70 on the average domestic electric bill to help fund a renewable energy program. Across the Atlantic, a government-appointed Canadian blue-ribbon panel is considering a number of measures to combat climate change, including a national fuel tax that would double the price of gasoline.