I've not looked at the spreadsheet yet but my own approach as a liveaboard sounds similar based on comments I've read so far. I know how much fuel the HR2 burns when I'm on the move so will keep a log of my travelling time then use these bits of information to calculate how much needs to be paid at the higher rate. Anything else I put in at each fill will be at the lower rate. I know this means I lose out slightly as the alternator is running when I'm on the move but this seems a bit pedantic especially as I'm expecting already 80-90% of the fuel to be lower rate in the winter months.
The fringe benefit is that I can easily use it as a log to show that I'm continuously cruising haha! Steve NB Bream
