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Comment Re:Could High-Speed Trains Shorten US Travel Times (Score 1) 138

Europe is plenty big. As big as the US but denser.

Sure most high speed companies run lines about 500km long, but there are plenty of connections through large parts of Europe that are high speed. And some individual runs are longer than 500km. You can travel through must of western Europe on high speed trains for distances much longer than 500km.

Someone talked about NIMBY and was modded troll, but the fact is they were right. Among the biggest opposition to high speed rail are NIMBY folks, and for understandable reasons. High speed, grade-separated rail really carves up the landscape, much like a freeway does, which deeply impacts people living near the proposed rail lines. Freeways have the advantage that their right of ways were carved out decades ago and people are used to them (and see the value). This could be true of rail also, but it would take several generations.

And when I see proposals to go from LA to SF, or from NYC to Chicago, I think that's great for people in those cities, but what about all the communities in between? What's the benefit to them? Is the high speed rail going to make some stops? By itself high speed rail comes up lacking in my opinion. We require much more than high speed rail, but that's never going to happen.

Comment Re:Hard and expensive (Score 1) 138

It likely means demolishing a lot of existing houses and businesses to make room for the train

It doesn't. What it means is cutting through a lot of big parcels whose owners have big money, so they can be big impediments. There has to be a happier medium than this between respect for individual private property ownership and the needs of the many, but we are clearly uninterested in finding it in this country.

Comment uh (Score 2) 15

Windows 11 users can add native support through an image extension from Microsoft Store

That's not what "native" means.

Who invented pluggable file formats anyway? The first place I experienced it was AmigaOS 2.0. NeXTStep had reusable controls but AFAIK it didn't provide formats to all installed applications.

Comment Re:It doesn't work at scale (Score 0) 25

I talked with Chat-GPT to understand its argument, and the gist was: the critique about low thermal conductivity was absolutely correct for the geothermal attempts between ~1970 and 2010. But modern “superhot rock” geothermal is operating in a very different regime.

First, they can now induce vastly more fractures in the rock. Heat transfer in geothermal isn’t about the raw conductivity of solid rock - it’s about surface area. More fractures = more exposed hot rock = more efficient heat sweep. The fracture networks used today are orders of magnitude larger than the old HDR trials.

Second, the water isn’t just hot water or steam anymore. At these temperatures and pressures it becomes a supercritical fluid. That matters because it convects heat through the fracture network instead of relying on slow conduction. So you don’t get the old “hot spot next to the well / cold depleted zone” behavior - the fluid actively evens out temperature gradients.

Third, the sites they’re using now (like Newberry Volcano) have massively higher heat flux from below. Many of the early HDR projects were drilled into generic crustal hot rock with weak replenishment. Near a volcano, the heat flow is orders of magnitude higher.

Add to that the modern toolkit - horizontal drilling (mid-2000s onward), high-temperature drilling materials, computer-modeled fracture design, etc. None of this existed during the early HDR experiments that gave geothermal a bad reputation.

Chat-GPT summed it with a metaphor: the old Hot Dry Rock systems were like trying to heat your house using a candle in the corner. Tiny fracture zones, minimal surface area, conduction-limited, fast local cooling and slow reheating.

The new approach is more like engineering a large underground heat exchanger connected to a huge volcanic heat source.

And yes, you can overdraw heat - just like you can over-pump groundwater. But operators don’t have to push it that hard, and modern models tell them exactly how much heat they can sustainably take each year.

I don't understand these topics deeply? I'm hoping that you do, and that this will mean something to you.

Comment Re:It doesn't work at scale (Score 1, Interesting) 25

I'm not an engineer, but here's what Chat-GPT thinks, when I shared your comment with it:

---

Not quite. This criticism is valid for old-school “hot dry rock” geothermal (1970-2010), but it doesn’t apply to the new superhot-rock designs.

It’s true that rock has low thermal conductivity and that conduction-limited systems cool locally if you withdraw heat faster than it flows back. That’s exactly why the early HDR [Lion: -- this means "Hot Dry Rock"] experiments never scaled.

But superhot-rock geothermal isn’t using the old model.

Three things have changed:

Supercritical water (>374C, high pressure).
At these temperatures you’re no longer circulating liquid water or steam. Supercritical fluid behaves like a gas in viscosity but carries heat like a liquid, and has dramatically higher enthalpy. It transfers heat through fractured rock convectively, not purely by conduction. That’s a completely different thermodynamic regime than the classic HDR studies.

Engineered fracture networks (modern EGS).
Today’s EGS looks much more like a controlled, high-permeability heat exchanger than a single injection well in a monolithic rock mass. You’re creating a huge surface area and letting supercritical fluid sweep heat through it. The limiting factor becomes the fracture network, not the bulk conductivity of a single block of granite.

Volcanic settings with very high heat flux.
The Newberry system is only a few miles from an active magma body. The heat inflow from depth is orders of magnitude higher than at the old HDR field sites. You still have to manage production rates, but you’re no longer relying on conduction through kilometers of cold crust.

The “if it were workable we’d already be using it” argument also doesn’t hold. We didn’t have:

* horizontal drilling at scale until the mid-2000s,

* the ability to design fracture networks with modern HPC,

* high-temperature drilling materials,

* or any commercial attempts at supercritical geothermal

until the last decade.

The physics hasn’t changed, but the engineering finally can reach the temperatures where supercritical convection dominates and where the geothermal resource is effectively thousands of times denser.

Superhot geothermal still has plenty of open questions (scaling, economics, long-term well integrity), but the “thermal conductivity of rock makes it impossible” critique is describing the previous generation of geothermal, not the current one.

Comment Re:Science self-corrects (Score 0) 29

The whole point of the label "Dark Energy" is it's a filler for an unknown that still needs to be explained.

The whole point of dark energy is to explain why the cosmos is expanding more than it theoretically should be. If it isn't, then you don't need dark energy, or if it isn't expanding as much as formerly believed then you don't need as much of it.

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