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Comment by legulere | Hacker News Reader

Meanwhile we use can use gamma radiation only by converting first to heat.

Really

Most of our "energy generation" is still based on 19th century physics

Sure heating stuff and turning water into steam is easy, but it might not be the most efficient way of turning some sources into energy

I know nothing about this but just did a little reading. It seems some direct nuclear to electricity methods are 90% efficient.

https://www.quora.com/Is-it-possible-to-convert-nuclear-ener...

PIDEC sounds like it works well with conventional IV gen reactors, achieving an extra 40% efficiency. ICC (a kind of DEC) seems suited to fusion and can exceed 90% efficiency.

I suspect the problem is that we've been building steam engines for a very long time, and have become very good at it. We'd be starting at zero, from an engineering standpoint, for PIDEC and ICC. It's a worthwhile task, but it would be billions laid down for something that has never been done at scale before (read: the government would have to fund the experimental reactor).

This has always bothered me. To think that we can induce nuclear fission, but then can't actually use the generated energy without boiling water and using it to turn a turbine!

Sometimes we just stumble onto a near ideal solution early. A chain on a cog for a bike drive for instance. People keep trying other things but they are all less efficient.

This is more efficient:

https://www.digitaltrends.com/outdoors/ceramicspeed-chainles...

It's a shaft with a weird gear at the end. The gear teeth spin on ball bearings.

According to whom? The manufacturer?

This company is known for selling snake oil products to amateur cyclists.

When I see this on Tour de France I’ll believe it.

competitive cycling doesn't let racers use whatever setup they want for their bikes.

if something is too good, like the really aerodynamic handlebars, they won't be allowed

Aero is quite regulated. So you can't play with wheel size, or various non-traditional bike designs. But other things seem like fair game, tweaks to geometry, different bearing technologies, new bearing races, electric shifting, disc brakes, etc.

The spirit of racing is that the race should be won largely by the best bicyclist, not the best bicycle. I'd expect a more efficient transmission would certainly be considered.

Disc brakes were also banned for pretty long.

Right, but aren't now. Progress is being made, fortunately mountain bikers (and their organizations) are much more open to progress.

Or at least tested by a well known 3rd party. There's been quite a bit of research on bicycle efficiency, if this worked I'd expect it to be big news in various bike research related circles.

For now I'm quite dubious, especially the claim that it gets more efficient the faster you go.

for pedalling speeds, my understanding is that a belt drive is more efficient than a chain

Not sure exactly what you mean. But every test I've seen shows the traditional chain is more efficient than a belt. The belt justifications I've seen are less maintenance, cleaner (no oil on clothes), and quieter. Never seen anyone claim it's more efficient.

Thus almost all bikes and nearly all motorcycles use chains, the higher the performance the more likely they are to use chains. However electric bikes (where efficiency isn't as important) or harley motorcycles sometimes use belts. As do folding bikes where you might come in contact with the belt.

But racing bikes or motorcycles are pretty much always chains.

Yea, but fission is just a fancy way to generate heat. Rest is basically the same. Turn it into mechanical energy, and then into electric by moving magnets vs coils.

The only other ways of generating electricity we use are different way of getting mechanical power, like wind or water, and solar cells. The latter is the only one on top of my head that's not mechanical.

Maybe making electrons move sensibly isn't that easy. Heat seems easy.

batteries and fuel cells, arguably the same thing. not mechanical or a heat engine.

Ultimately, we have only improved upon our two earliest tools: fire and pointy sticks.

I’m amazed by it. Using a low cost molecule’s phase change, electromagnetic material stimulates electrons in high temperature conductive material.

Actually in a lot of cases turning heat into steam is MORE efficient than alternatives. Direct thermoelectric conversion has an efficiency of 5% to 10%, whereas multistage steam turbines are 36% - 42% efficient.

This is also the reason why kilopower (a replacement for RTGs) is looking to replace thermoelectric conversion with sterling engines that are 30% to 34% efficient.

Unless you avoid producing heat (in the thermodynamic sense), the Carnot efficiency is a hard upper limit. A fancy steampunk apparatus to harness heat near the Carnot limit is still optimal.

Improvements come from running hotter or from avoiding producing heat in the first place. Some newer nuclear reactor designs output their heat at very high temperature, and devices like fuel cells and direct capture of beta particles can, in principle, exceed the Carnot efficiency available from using the fuel to heat something.

There isn't any other reasonable way.

Direct thermoelectric conversion usually peaks in at about 10% effiency on the top end.

Steam Turbines can hammer down 40% and more easily.

Well, that’s how these organisms do it as well.

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