IIRC basic thermodynamics shows that ordinary steam engines can't be very efficient. So, don't get good MPG or miles per bucket of coal, or whatever fuel. IIRC the main reason for diesel-electric locomotives for trains and large ships was that it was significantly more efficient than just steam, at least steam with just a boiler and pistons. Of course, really large ships generate steam and then run it through a steam…
Stream engines are no longer used on large ships (except for nuclear powered warships). Merchant ships now use large 2-stroke diesel engines for maximum fuel efficiency.
Yup, the nuke ships are what I was thinking about -- wasn't sure if there were any other examples of pushing steam through a turbine.
> If electrics had been chosen and had 100 years of continual minor incremental improvements... Battery technology is still basically just ordinary chemistry and, thus, hasn't made much progress in 100 years. E.g., we use a lead acid battery in cars now, and they had lead acid batteries back then. Just look at the periodic table, pick some elements, and make a battery. They did that 100 years ago also. If we do somet…
Sure, but lead-acid and zinc-carbon, both 19th century technologies, were the main - essentially only - types of batteries until the age of the Walkman in the 80s. Then we got Duracell alkalines and cute adverts. Until then there wasn't a lot of pressure to get better, so they mostly didn't and they wouldn't have sold anyway. Around the same time rechargeables got some development pressure in the form of mobile phone…
Be careful: For the improvements, are close against some quite fundamental chemistry and physics. E.g., for fast charging, the battery has internal resistance, that is, gets hot when charging. Likely the amount of internal resistance varies, but charging as fast as filling a 20 gallon tank of gasoline might encounter something impossible due to the chemistry/physics. Fast charging is one of the reasons for the pursuit of capacitors instead of batteries, e.g., the EEStore effort with barium and titanium. The capacitors also typically are able to discharge much faster than batteries. IIRC, battery charging is a chemical reaction where have to move atoms around. A capacitor, first cut, just moves electrons around. But for research time, EEStore has been at it for some years now.
In many cities bikes are faster than cars. In central London for example average speeds are around eight miles per hour (and falling). During rushhour it's even worse. Rushhour traffic in Berlin averages around five miles per hour. Even untrained cyclists are faster than that.
But would you like to be in rush hour traffic on a bike?
In many ways, it's actually better cycling in dense urban traffic moving at a snail's pace than say, a 5 lane road (2 in each direction, shared center turn) of the sort that are arterials in suburbs or might find near your local mall when traffic is moving at 35mph.
Source: I've put about 14,000 miles on a bicycle, half touring, half commuting in Cleveland and Boston. for context, that'll seem absurdly large to non-cyclists, and quite small to serious cyclists.
Some of the reasons why petrol won: There was no electric grid to speak of - even now there is concern the grid can't support all EV's, once you were outside the cities (and there weren't many back then) the grid was spotty. The miracle of being able to pour some cheap liquid in an engine and drive for miles is a considerable achievement. Lead acid batteries weren't very good and were expensive (and still are) and do…
Power control is also a massive consideration - doing more than on-off basically requires semiconductors or wasting a lot of energy in variable resistors. Some old systems had two-speed control by swapping batteries between series and parallel. One of Tesla's less obvious innovations is going beyond silicon to silicon carbide for high-power control: https://www.systemplus.fr/wp-content/uploads/2018/06/SP18413... Milk…
We already got them back around here, since a few years ago, mostly used by mailmen.
Battery technology has been, and to a certain degree still is the limiting factor for electric cars...and the fact is that gasoline is still a denser form of energy storage than batteries by volume, weight etc.. I'm saying this as a someone who prefers electrics over ICE...
I think that if, then only in terms of cost. Every quarter or so I do a 1500km(935 mile) trip and back. Nowadays it takes me two days, because I realized that spending around 20h behind the wheel without rest is simply dangerous. My car's highway range is about 440 miles - but I rarely drive that far without refueling because the longest distance between my usual stops is 350 miles. And once stopped I don't just fill…
I've done a roadtrip from Montreal to Atlanta in a Model S, back in 2015. I've found that by the time the battery runs low, you're due for a break anyway, so it doesn't really change the way you travel that much.
So I started reading popular mechanics 1905-2005 last weekend, in the first issue of 1905 they actually show a little blurb about electric mail trucks, I knew EVs went way back but found it pretty neat.
The 2019 Tesla model S has a range of 370 miles, and I assume that as time passes, more EVs will have a range approaching that figure. That range is considerably longer than the range of my bladder, so once charging increases in speed, this "problem" simply vanishes. We're already on our way there, the first 250kW charger opened this week, and will add 180 miles of range in 15 minutes. In fact, it's better than an IC…
How long does it take to charge? Granted 350 miles is a long trip, but some 9f us drive from Seattle to San Francisco and we can't do that in 350 burst waiting overnight for the car to charge. Personally I think a hybrid that plugs into 120, with a commuting range 50 miles and a back up gas engine will be the sweet spot
Lithium-ion batteries can be fully charged safely in about an hour, give or take, regardless of their capacity. 80% charge is about half that, IIRC.
The reason it takes a while to recharge EVs is because of the enormous size of their batteries. Tesla Superchargers inject more power into the car than what comes into a regular home.
Quick math: A 100KWh is going to take a bit more than 100KW of power to charge in an hour. For comparison, an oven uses about 3KW...
In many cities bikes are faster than cars. In central London for example average speeds are around eight miles per hour (and falling). During rushhour it's even worse. Rushhour traffic in Berlin averages around five miles per hour. Even untrained cyclists are faster than that.
But would you like to be in rush hour traffic on a bike?
You end up going faster than the cars trapped in the gridlock because you can filter to the front of the intersection easily on a bike.
adding mass increase the costs of tires (ongoing) wheels, shocks and other suspension bits that have to be stronger and bigger to support the mass, and it increases wear on roads too. so energy density does affect upfront costs and lifetime costs.
Sure, but if you're going to go that direction with your argument you need to account for the environmental damage caused by burning fossil fuels inefficiently in motor vehicles.
Tires are the largest maintenance cost for cars, so that's absolutely a valid consideration. The rest of the argument is junk though.
For trains diesel electric lets you really simplify the power-train. Imagine powering all those wheels mechanically, yeah, not happening.
The most common diesel-electric locomotive today has 6 drive axles. The big steam locomotives designed at their twilight sported 6-10 drive axles, and the most famous and successful of them (the 4-8-8-4 Big Boy) ran 8 drive axles. Mechanical linkage of drive axles isn't what killed the steam locomotive.
Mechanical linkage for multiple direct drive external combustion engines that can operate at 0 rpm is far simpler (the drive axles are basically the crankshaft) than for a single internal combustion engine that must maintain a minimum engine rpm and has to be geared down to axles that are riding on a bogie that pivots separate from the deck of the engine.
To take advantage of the increased efficient of an internal combustion engine you'd need a lot of mechanical complexity unless you go hydraulic (solidly defeating most efficiency improvements) or electric.