Guardian: The former vice-president credited with rejuvenating America’s environmental movement today issued a challenge to its people: End the use of fossil fuels for electricity within 10 years. Al Gore’s call to end the burning of carbon for power, delivered before an adoring audience in Washington, was clearly aimed at vaulting renewable energy to the top of the presidential candidates’ agenda. “Our dangerous reliance on carbon-based fuels is at the core of all these problems – …