Driving in Winter.

You are correct on dynamic braking except for one point. Heat is still created. When you drop the magnet down the copper tube, electrical current is generated in the copper. When stopping heavy loads, this eddy current can be substantial and creates heat from I²R losses in the copper. In fact, it would be exactly the same amount of heat you would get from friction breaking.

Yes but not in the same place.

Large copper "fin" is in its self a heatsink, and the heat is not on the surface of a friction pad that resists heat transfer, and in that friction, wears down at the same time, so is easier to dissipate than a heavy brake drum and friction pad set, or even disk.
From what I can find, the heat is dissipated a hell of a lot easier, yes they have to find a way of creating a heatsink that can cool, but because of the lack of friction, the brakes last longer under heavy braking than traditional brakes, and you dont get brake fade.
This is why the interest from heavy haul...

I would love to find a way to incorporate this technology into long downgrades on either railroads or freeways. build a system that generates power as it prevents vehicles from running away on the downgrade. it would take a lot of engineering to make it work, but it is an interesting thought.

never noticed an electric locomotive going down donner pass on the freeway or on the rails... and not many cable cars around there, either. haven't noticed any going over the hill by Butte, either. lot of trucks riding the jake, though.

not every trucker drives a Tesla.

And judging by the price he will be charging, no trucker will be driving a Tesla at that point either?.

The idea around back-EMF braking, which in truth, I have already on a Monster truck radio Control vehicle, is bloody good, except its expensive, and it weighs a few tons.
The problem now is that the full load can weigh no more than combined 44 tons.
Either they combine an extra axle and go for an axle weight limit, or, the full load on a "semi-" or Artic, will be compromised by heavy battery configuration.

Dont get me wrong at all, I am no longer a doom-sayer in Electric vehicle and will never be saying this will never happen, because I can see it happening soon, its just, not that soon, because they aint finished twiddling with it yet.

When, not if, but when, when they can replace a 900 horsepower diesel and tank full of fuel, with a 900 horse electrical engine with 500 mile battery that has a 45min recharge time to 80%, and can do that 500mile in Winter with the Heating up full retaining a 20degC inside in a Minus 5 outside, and then repeat with a 20degC inside in a 40degree outside during summer, whilst towing a "refer" van, refrigerated, and also plan on at least 100 mile of those 500 mile in maximum walking pace traffic, do all that, be able to keep a refer refrigerated overnight on a long haul run if there is no hookup, between charges, and bring all that in at an affordable price or price plan over say 5 yrs that matches an average running cost of a diesel, than we have progress.

900 horse diesel, it has to be that option, because thats whats expected of todays heavy haul.
45min recharge, thats the legal requirement on a lunch break, plug the tractor in and go get lunch, full charge when you finish, is a good plan to attract Truck drivers to your Truck stop during the day.
5 yr payment plan, to make it affordable, if you price out what it costs in Diesel to run a HGV for 5 yrs, and do a lease plan that rents out or Hire purchases a vehicle that makes it economical to do that over a 5 yr plan, you may have a gold mine, if it works out cheaper to run Electric than it does to run a diesel over that period.

But at the moment, the difference between a Diesel truck and a Tesla for initial purchase.... aint nobody got the brass to take that risk?.

Just for consideration.
In Winter, sudden road closures, whilst you are on them, may be of concern, especially f you are stuck for several hours.
Keep that in mind when thinking "I have enough fuel for today"....
Do you really?.
How many hours will half-a-tank of fuel keep you warm for if stranded in the snow.

Hmmm... now there is a thing... is this worth putting as a myth to be tested to see how much fuel is used per hour keeping a stranded car warm enough to survive in?.. how would you propose that idea to the MB's?..

Diesel electric locomotives use dynamic breaking heavily. Normally the power generated by dynamic breaking is sent to a large bank of resistors and dumped off as waste heat. I actually don't think it would be that hard to setup a switching system that would send it to an outside connection. My first thought would be sort of an inverse of the electric rail supply lines that trains currently use. Instead of feeding power to the train, the train would feed power to the local grid.

If you have a area where you commonly run the dynamic breaking on a down grade, you could setup the power lines and let the engine and physics do its thing. There are plenty of grades through the Rocky Mountains that would be ideal.

Two challenges I could see.
1. Equipping your fleet. time and money, bit not very challenging from a technical stand point.
2. What will the grid do with that power? If you have a train that takes 3x3,500 HP engines to control it on a down grate, that is 10,500 HP worth of power or 7.8MW of electricity generated. That is a lot of power for a grid to be able to absorb and react to in a short period of time. You either have to have some way to store that influx of power and then release it as needed, or a grid designed with enough capacity that can be shut down quickly enough to allow for the new source of energy.

I wuoldn't expect it to be a fast dump, so the grid control systems would be able to throttle back combustion fueled power plants as the power came into the system.