Gensets vs Inverters
WS, I think you need to give yourself and us some more info. What will your AC needs be on the boat? Powering a tool or occasionally running a microwave? An inverter (and a properly matched DC electrical system) is the easy answer. Air conditioning, running an AC frig or heating the shower water are at the opposite end of the spectrum.
How will you be using the boat? If an occasional vacation cruise, you can purchase a lot of slip comforts enroute for the price of either one. Long term cruising? Then you may find it inviting to have a secondary power generation source (genset) or worry about being dependent on something that will possibly fail.
What about the budget? How important to you are things you will live & sail without if you buy the much higher cost genset? (Notice that''s "higher cost", not "higher price", since with gensets you keep on giving).
How easily can your Irwin swallow the genset? Where will you put it and what effect will that have on trim? On sailing in a lumpy sea or a steep chop? Do you have adequate fuel tankage? Will extra room need to be found for fuel jugs or an extra tank?What storage do you give up, and how will you feel about access for servicing if you install the genset. (The inverter is usually an ''install & forget'' item provided you give it adequate ventilation). And when thinking storage, don''t overlook the fuel & oil filters, impeller kits, special tools and the other items a genset will expect of you eventually.
And finally, what ''emergencies'' do you hope to cope with better by using the genset? Perhaps that''s where I should have started, since I can''t think of any and would worry about a genset being considered ''emergency equipment''.
In my limited experience, a boat, her crew and her budget all experience heavy compromises when bringing a genset aboard. Which doesn''t mean it''s a bad thing for some boats & crews.