A look inside the fusion energy device under construction in Mass.

Workers in Devens, Massachusetts, are building a fusion reactor that will operate at temperatures hotter than the core of the sun. If it works,  Commonwealth Fusion Systems' device will provide a new source of clean power.

Scientists have been trying to solve the riddle of fusion energy for decades. Scott Kirsner, a columnist with our editorial partner MassLive, joins WBUR's Morning Edition to report on Commonwealth Fusion Systems' progress.