I see the appeal of tank to tank miles as part of the game. 800 miles on a tank is a benchmark I may try to achieve someday, and I do enjoy gaming the vehicle and gravity for excellent, no, incredible MPG. But other than adding an additional trophy to your collection, why do it? The only true benefit is lowered weight as the tank empties as I understand it. When I see cheap gas (like today at Costco $178.9) I jump on it, even though I had over a third of a tank and 240 miles until empty. And then there's full-tank-syndrome, from which I suffer. Let's say the internet goes up in flames or the electrical grid is compromised and you need to travel now (don't say it can't happen). Having 700+ mile range in your tank is comforting. Or use your Prius as an emergency generator. Yes, a small part of the appeal of the Prius is its usefulness when and if a crises occurs. I'm no hard-core prepper, not even close, but it just makes sense to keep your ride locked and loaded (and no, I do not carry, but would if conditions required).
No need for hypotheticals when you can draw from actual experience right here in the U.S.: Alternate day gas rationing during an energy crisis / OPEC Oil Embargo. Does anyone else remember 1973 and 1979? News reports of that era included stories about people with strong reason to make specific trips on days when they couldn't legally refuel. They had to do some serious juggling, including pre-staging another family vehicle along the route. I have a frequent trip that exceeded the single tank range of the cars I used in that era, and was a stretch (but possible with a well understood tank and careful driving) for some subsequent vehicles. Then, sometimes, the known good cheap gas (e.g. the Costco you mention) happens to be a long way away along the route. Better knowledge of how far the car really goes, is helpful with that fuel planning. But I still harvest those opportunities even when the tank is over half full.
I usually fill up when the gauge gets down to the last bar. But with the way things are going in the U.S. lately, I may just start refueling when it hits the 1/2 tank point. (Possibly add a few more items to my emergency kit in the trunk, too.) And did you see the latest news from France? I guess the "800 mile challenge" is fun once or twice; just to see if you can do it. (I have not.) And it's nice to learn the capabilities of our Prius. God forbid, if we had some kind of terrible natural disaster out here, there would be so much panic and traffic, people wouldn't be able to get out of town... but it's nice to know I have a vehicle that gets 60 mpg in case I have to relocate.
Answer: Efficient driving for a 1,000 mile tank | PriusChat I simply applied lessons learned from 10 mile benchmarks over a three week interval in my driving stunt. Whether or not anyone else tries, the cook book is well documented and can be repeated by anyone. Bob Wilson
