With the signing of the Paris climate accord on Friday, Earth Day 2016 marks another moment of unusual political alignment. One hundred and ninety-five sovereign nations, each with their own deep dependencies on fossil fuels, are committing to carbon cuts so ambitious they could ward off the catastrophe that scientists have warned is all but inevitable...But an agreement is only that. Once the ink dries on the world’s first global climate pact, we’ll have the harder part ahead of us: heeding the call to action, as businesses and citizens and members of government, just like another generation did nearly half a century ago...How can we turn the Paris accord into reality? As the number one source of greenhouse gas emissions, electricity and heat production is the biggest, best lever available. Driving a clean energy future will require fast, coordinated action across the entire energy supply chain...The most critical players are the businesses at the nexus of it all: utilities...The big picture is business model transition. Utilities are pivoting away from selling electrons, and toward connecting homes and businesses to a clean, distributed energy system. With new technology, power companies are getting ready to give billions of people the tools to advance the agenda set by the Paris climate agreement. That kind of change looks a lot different than what unfolded on Earth Day, 1970. But the fundamentals are the same. Progress is happening because of surprising alignments — between nations, in government, in industry, and among people. We’ll need to strengthen those bonds going forward. But with smart regulatory policy and ambitious reforms, the world might remember this Earth Day as the one where we finally started pushing in the right direction.