One of my force-multipliers is the Inmotion V5F monowheel [1]
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)
I recently purchased a V10 (25mph max speed) for NYC. It is indeed amazing, but I don't think its accessible to most. You have to have protection gear which can be a nuisance, perhaps after you get confident you can wear less while being conservative in riding. But in general it's not nearly as safe as a bicycle.
Why would you get stuck, though? I'd assume that you can jump off. The high speeds part is risky, but if you don't go fast (15-20km) I assume you should be ok?
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%