National Public Radio: President Obama and his counterparts from Canada and Mexico are preparing to unveil an ambitious new goal for generating carbon-free power when they meet this week in Ottawa.
The three leaders are expected to set a target for North America to get 50 percent of its electricity from nonpolluting sources by 2025. That's up from about 37 percent last year.
Aides acknowledge that's a "stretch goal," requiring commitments over and above what the three countries agreed to as part of the Paris climate...