Drag a towing generator to make electricity as you sail. Use this to run a watermaker to get fresh water. Run the fresh water through a -tiny- electrolysis plant. Using the same power from the towing generator, break the fresh water down to hydrogen & oxygen. Store the O2 to sell later and store the Hydrogen to run your engine when you need it.
Most likely the math will work out that you'll need to cross the Pacific down wind to get enough Hydrogen to get to your dock at the end of the passage though..