The shuttle wasn't thrown away, nor were the boosters - only the (rather simple) ET. How did that work out, price-wise?

It's simply not fair to pretend that launch costs are a minor issue. They are the limiting factor, and progress in reducing costs has been lethargic over the past decades. "in orbit operations" are expensive precisely because launch costs are so high. Bargain basement, pay-out-the-nose-for-insurance launch rates are $4-5k a kilogram. More typical Russian rates are about $6-7k, while typical US and European rates run about $10k. And that's for large payloads, for small payloads expect in the (very) rough ballpark of $20k. How do you expect to live affordably in space if launch costs are even within an order of magnitude of that?

That's not to say that rockets fundamentally can't provide cheap access to space. But today's rockets certainly can't.

Presently working or theoretical? If you want "presently working", then that would defeat the point of asking for suggestions, would it not? If you want theoretical, there's tons. I kind of like the Launch Loop concept - sort of like a space elevator except that it doesn't require unobtanium, avoids or reduces the countless other problems with space elevators (micrometeorite damage, oscillation modes, power transfer, lightning and ionospheric discharge, and about 50 other things), and it gives you much more ideal/customizable orbital momentum, plus is 1-2 orders of magnitude more energy efficient at lifting cargo (space elevator climbers have to rely on beamed power, there's no practical way to send it through the cable, and beamed power over great distances where one receiver is only a few square meters at best is very low efficiency) AND offers a far higher launch rate.

Earth-based space elevators, the stuff of sci-fi nerd dreams, really are an awful solution when you start looking at the details. There's far better solutions out there.

Space has resources. They're called asteroids. Often quite valuable resources, actually - although learning to mine in microgravity will be a trial-and-error process.

Let's be honest, the main sellable goods of a Martian colony would be martian minerals for the jewelry / collector industry (which would sell for many times their weight in gold... a fundamental requirement of martian exports, given the cost of return payload deliveries) and tourist trips for the few multi-billionaires obsessed with space. It's hard to envision in even the medium term much more coming from a Mars colony than that which could pay for itself. And these things wouldn't come close to paying for the cost of the colony, in any regard. I certainly don't expect to see, say, industrial minerals exports in the medium term; a "creative economy" means people which means ridiculously high upkeep costs; and the concept of martian manufacturing being competitive with Earth's is just laughable. And science is much more cheaply done with disposable robots. One could probably factory-produce a hundred Curiosity rovers and mass launch/land them in every corner of Mars for the cost of one manned mission (let alone a "colony"). One could probably launch an automated nuclear submersible-drillship into the oceans of Europa for less than the price of one manned Mars mission.

If you thermalize your fission fragments. Sure, that's what all current fission reactors do, but it's not a fundamental requirement. About 80% of a nuclear reaction's energy is in the form of fission fragments - high energy heavy ions - which can be decelerated for power without Carnot losses, without a thermodynamic sink. The key is that you can't use fuel elements with any serious thickness to them (otherwise most fragments will thermalize) - the fuel elements have to be wires, sheets, dust, things of that nature, with magnetic fields to separate the fragments from the fuel.

On the other hand, when it comes to propulsion, nukes are the bees knees. No form of currently-achievable propulsion yields a higher Isp than a fission fragment rocket, with the exception of photonic / magnetic sails, which are impractically low thrust for interplanetary travel. Some day I'd love to run some simulations as to whether you could have a spallation-driven subcritical dusty fission reactor get rid of much if not all of the moderator mass (power to drive the accelerator should be copious from a fission fragment reactor), and whether you could run one in an infrared nuclear lightbulb mode (making use of the electrostatically-contained dust's extreme surface area and low IR absorption spectrum to get high output, rather than using extreme, unmanageable temperatures to get high output as in a traditional nuclear lightbulb concept), thus opening up non-dirty high thrust power modes for surface operation (airbreathing, simple fuel heating, etc, including using electricity from fragment deceleration to run a microwave beam to help ionize the air/fuel and make it more opaque to IR) and a few other space options (such as a nuclear VASIMR-like mode)

People who didn't learn to code by the time they were 7 have never been able to program as adults. It sure is lucky a supply of people taught to code by ancient alien astronauts was supplied to us so we could bootstrap the procedure, because no one in the history of our species has learned new skills past age 7.

That's not true, the mAh levels of batteries keep rising as the batteries themselves shrink. And while there have indeed been some improvements in electronics efficiencies, these have been largely offset by increased demands in various roles.

Li-ion loses a negligible percentage of its energy as heat. A li-ion pack charged over the course of an hour or so is usually around 99% efficient. Surge charging can drop it to 94-97%, depending on the chemistry and rate, but again, li-ion is very efficient. Flywheels are much lossier. They're also more expensive, larger, and have more catastrophic failure modes.

Nope, can't do that.

High power chargers are DC straight into the pack. You don't get to choose the voltage. If you tried to run high voltage in the cable and a converter in the vehicle, one that'd be a massive converter, and two, cooling it would be a huge problem in its own right.

20KW would *melt* domestic feeds even before you get to the meter.

I don't know about you, but my new house is going to have a 100A feed. It's not that unusual. 100A * 240V = 24kW.

Secondly, ulltra-fast home charging rates are irrelevant. Seriously, in what scenario is that necessary? Home charging is for overnight. Fast chargers are only needed on highways.

This is not going to suddenly "change everything". First off, there's so little info here you can't even see through the hype. There's nothing to get an idea of how hard this would be to commercialize, what its energy density would be, or any of tons of other things that make a big difference. And secondly, these are hardly the first lab-scale batteries to have properties like this. Heck, there have even been lithium titanate batteries commercialized before. Crazy charge / discharge times, but they were largely a flop except in niche applications - the cost was way too high and the energy density too low.

There is every week or two some great research breakthrough in battery storage. Most of them you'll never read about. Most of them will never go anywhere. But a few will. And they will slowly, inevitably make their way into the battery technology of tomorrow. Silicon anodes, for example, were once among those crazy lab future battery techs. Now they're in commercial cells. People never stop to think about how little the batteries in their phones have gotten in an area of increasing computing power, larger screens, greater demands on lifespan, etc. Energy density continues its inevitable march.... in the background. But the odds that any one tech that you read about is going to carry the industry is very small. And these things take half a decade to go from the lab to stores.

And of course, the assumption that if your station's maximum output is 10 MW that you have to have a 10 MW feed to the grid is also wrong. It presumes that you can't have a battery buffer in your station. Look at your typical gas station; pumps spend by far most of their time idle. A charging station with a peak output of 10 MW could probably meet all its needs with a 2 MW feed and a 20-minute battery buffer (although a statistical analysis of consumption patterns would be required for specifics)

It's not at all reasonable to reharge the entire pack every 17.5 hours. If your car has a 200 mile range, and you're charging that fully every 17.5 hours, then you're driving 274 miles per day.

In a naive calculation, one can easily determine that the charging cable would be way too heavy and unwieldy for a person to use.

Of course, that's the problem with naive calculations. The solution in practice for very high power charging is very simple, just cool the cable rather than requiring it to be passively air-cooled.

Personally, I think very high-power chargers should also provide coolant for the vehicle, through the charging port. It makes a lot more sense to me to make a small number of chillers (aka, part of the chargers) which can keep a store of coolant than making every single vehicle have to haul around a high power chiller and coolant reservoir. Coolant comes from the charger's reservoir, along its switching electronics, down the cable, into the vehicle, into its pack, and then heated coolant is returned on the cable's return line