Transformers and Short circuit
It's not like a solar panel being shorted i.e. the sun stays the same brightness despite the short. A transformer converts electrical energy to magnetic energy and then back to electrical energy. It does it with pretty good efficiency (90%+ on most transformers). If you short the secondary, the primary takes a lot of current. It's the same with an electric motor - if you lock the armature, you take a lot of current/power/energy.