In answer to Bob Austin's post: Bob has some valid points for operating in the real world but not as valid for operating in make believe world on the computer as many of us do. Yaaah you people KNOW who you are! To quote>>The alternator probably will not be putting out 130 amps all of the time. If it is, you probably need to rethink the charging system and power utilization. << I put the need for alternator in at 5hp for 6 hours figuring a battery depletion of 280amp hours and high use of electrical during the run. 5hp is less than 130 amps. >>I am a bit puzzled by your statement that you want to run Air Conditioning during the day. If you are going cruising in a small boat you should design in good ventilation so that AC is not necessary. << AC is one of the elements of life. >>How often will you deploy paravanes on a 26 foot boat? << This boat will be operated nearly 100% of the time in the open waters of Lake Erie and the great lakes. I would estimate 80% of the time. >>Other than "bragging rights" ie: my boat gets better fuel mileage than...... If your boat gets 10 mpg or 1 mpg, the fuel cost and range is really not important in the over all cost of owning and running a boat for over 95% of boaters. << On the computer and in one's dreams, range and bragging rites are extremely important. A 26' boat cannot be expected to cross the Atlantic on a mear 80 gallons. In real life- ehhhh- I am considering removing a 20 gallon tank, thereby reducing down to 60 gallons to increase room, reduce weight and reduce complexity. One thing from my calculations is interesting. A range reduction with a corresponding gain in speed is not anywhere near as big a penalty because of the high accessory loss. S/L 1.16 or 5.5 Kts hp 6.87 + 7.8hp* loss = 14.67hp Range = 524NM S/L 1.37 or 6.5 Kts hp 11.35hp + 8.2hp* = 19.55hp Range = 465NM *The increase in hp of accessory loss is a WAG on increased power required by the paravanes. The reduction in range when going from a S/L of 1.16, well under hull speed to an S/L of 1.37, slightly over hull speed is only 11% because of the high accessory losses on a boat this size. The moral of this? Throttle up baby, the range is there, the engine is operating is a better power range and the fuel increases are acceptable. Acceptable? I guess so, 6 hours at 5.5 Kts is 33NM. I can do the same distance at 6.5Kts in 5 hours. The fuel I would save by slowing down would be 0.56 gallons or about $0.78. Ahhhhhh, yahhh, no brainier, I guess an hour is worth $0.78 too me. With all of these calculations we can sure lose the forest for the trees eh. One thing about dreams, they don't cost a thing, your are never scared out of you're wits, there are never problems that you are not dealing with in a super hero fashion and they provide hours of entertainment. Just my 2 cents worth. Kurt Reno 69 GlassCraft 26' trawler