At its heart, the Fusion Energi has always been a gas-powered car converted to become a plug-in hybrid. On account of that, it comes with inherent flaws and limitations that cars designed from the outset as plug-in hybrids – like the aforementioned Volt and Clarity Plug-In Hybrid, and others like the Prius Plug-in Prime – don’t have. The aforementioned tiny trunk is one. Another is the fact its body is not as aerodynamic as it could be. Yet another is weight, which wasn’t as significant a consideration for Fusion engineers when this generation of the car was being developed.