Well, in case I haven’t said it before, heat is one of the primary factors that can cause premature failure of electrical devices and replacement of a modern high output alternator is an over $1000 expense. Not exactly pocket change in my book. So, there are several ways to deal with this issue, one is a temperature sensor mounted on the alternator that is keyed to the system voltage regulator and basically turns the alternator off when it gets too hot. Additionally, offering up a more effective cooling system for the alternator than basic engine room ventilation (especially on sailboats) is a great idea. The blue duct work you see in the above photo actually has a directional vent vane much like you see on the dashboard of your car and its aimed right at the alternator above it. Cool idea…………………………..