Typically bigger does mean higher efficiencies because of required auxiliaries. But big powerplants usually involve combustion.
Becaureful not to expect real knowledge from journalism today.
I know things change rapidly and since I was in school there are a host of new Sciences now That said,When someone tells me they can achieve greater efficiency with a engine driven generator powering a motor, than I can with say a simple Chain and sprocket from the engine. Bells go off and the BS flag flies.