The global transition from carbon-intensive fossil fuels to cleaner, more reliable renewables like wind and solar is well underway. But the big question — for the 2020s and beyond — is how fast it will happen.

A slow transition would mean that energy-sector incumbents continue to flourish and we would all but certainly miss the emissions reduction targets enshrined in the 2015 Paris climate agreement. But if the transition is rapid, incumbents will experience varying degrees of disruption — the price of keeping the Paris targets well within reach. As matters stand, both scenarios are possible, representing two paths that lie before us.

In a new report for the World Economic Forum's Global Future Council on Energy, we and our co-authors identify four key areas that will determine which path we take. The "Speed of the Energy Transition" offers compelling evidence that the transition is coming fast and that all stakeholders in the global energy system — which is to say, everyone — must start preparing.