Man on a bicycle can go three or four times faster than the pedestrian, but uses five times less energy in the process. He carries one gram of his weight over a kilometer of flat road at an expense of only 0.15 calories. The bicycle is the perfect transducer to match man’s metabolic energy to the impedance of locomotion. Equipped with this tool, man outstrips the efficiency of not only all machines but all other animals as well."
This is among my favorite devices of all time. It is quick, nimble, and lightweight. It has completely replaced walking, a car or a bicycle for my local trips. While there is a learning curve, unlike a bicycle, it has required almost [2] no maintenance in ~4000 miles of riding, and both hands are free to hold things so I can carry much more than I ever could on a bike. I've transported a desk, groceries, a 50 lb box of firewood, gardening tools, and so on. Plus, riding one is just plain FUN: it feels like skiing or flying. You really have to try it to know.
A pessimistic estimate of the V5F monowheel's efficiency:
* Battery = 320 Wh = 275335 calories
* Weight = 12 kg for the device, so with a rider around 95kg
* Range = 20 km on the low end (25-30 km is typical, manufacturer claims 38±3 km)
Efficiency = 275335 calories / 95000g / 20km = 0.14 calories/g/km
An optimistic estimate given my actual riding experience:
Efficiency = 275335 calories / 91175g / 30km = 0.10 calories/g/km
[1] https://www.myinmotion.com/products/solowheel-glide-2
[2] It still works just fine despite me beating the hell out of it, but the battery has worn down to ~70%
So, that seems low to me. I would expect you to burn more than 10 kcal, but it seems the right order of magnitude at least.
I wonder whether this will still hold true when the costs of building and maintaining
1. a bike
2. a flat road to ride the bike on
Take all the transportation conveniences a regular bike can without getting sweaty.