By Jeremy Deaton
At the start of 2017, just 22 cities had committed to sourcing all of their power from clean energy by 2050. As of this week, that number is 72. Since President Trump moved into the Oval Office and started ripping up federal climate policy, dozens of cities in conservative states have set ambitious goals for clean power, including Salt Lake City, St. Louis and Atlanta. Now for the hard part. These cities must chart a course to reaching their goal.