Originally Posted by sailingdog
Some of the boats I'm talking about burn 20-30 gallons or more an hour. With fuel at $4+ per gallon... it wouldn't take too many hours for them to pay for my sails in fuel costs.
Some sailing boats have bigger sails too, so you ought to compare like-with-like in some way.
So take a motor boat with the same tonnage and average speed as your tri for comparison. Include all your sails and the life that they actually have. Or put another way. Take off your mast and sails. Work out their value, how much fuel does that buy for your engine?
In my case, my engine drives my monohull at the same hull limited speed as my sails (about 8 knots). I actually calculate an average speed of 5 knots when cruising to allow for low or head winds. My engine drives my boat at 5 knots using about 3 litres/hour.
Just approximately, if I had to replace all my sails, boom, mast and rigging, it would cost maybe 40-50k euros. At your fuel prices, of about 0.73 euro/litre, that should take me about 100k nm or some 20k propulsive hours. I would not expect my sails (or my engine) to last that long. But replacing my engine is cheaper than replacing the wind propulsion system.