If the boat is set up properly it could work. My buddy's 47 Fountain has 2 transom pickups that feed the Genset and the AC system, since both are well fed you could run them at speed. He never has, but we may give it a try just to see how it works . In most performance boats a built in AC system will cool the cabin in 10-15 minutes as cold as you want it, since there isn't that much air space and no windows the AC works VERY well.

You can run the built-in AC units on battery power with an invertor. I've done it in a 26' cruiser using a small 5000btu unit, a 2500 amp invertor and 2 batteries. The small units are more than enough for a cabin of a sport boat up to the size of a 35 Cig.

I have a carry on cruise air for sale 350 sounds fair let me know

Jim

There is always the dreaded fan! low weight, no spills ,no drips, no cooling!!! A little sticky down there