Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Steam Networks

worksinprogress.co

Post reply on HN
Print view View original

111–120 of 161 posts

Re: Steam Networks

#111

Post by shagie »

coryk135 wrote: post #25

This part really caught my attention: > in 1962, the anthracite seam under Centralia, PA – 25 miles to the west of Lehigh County – caught on fire and is still burning today.) That’s crazy to think that for over 60 years there’s been an underground coal mine on fire. I wonder how long the mines will burn for. The pictures on Google are quite interesting.

When you're driving through North Dakota and see the red clinker in the cliffs along the highway...

https://www.dmr.nd.gov/ndgs/ndnotes/ndn13_h.htm and https://www.dmr.nd.gov/ndgs/documents/newsletter/2013Winter/...

> Several early explorers reported coal fires in the northern Great Plains region. Over the years, range fires have ignited lignite beds many times. In two places in western North Dakota, in Theodore Roosevelt National Park and near Amidon, lignite seams were recently burning for many years. A seam of lignite at Buck Hill in the park burned from 1951-1977.

And that's the modern history.

> Years ago, during fieldwork on the major buttes of western North Dakota, John Hoganson and I discovered clinker pebbles in the Arikaree Formation indicating that coals had been burning prior to when these rocks were deposited some 25 million years ago. Probably as far back as 40 million years ago, when grasslands were first established, fires have swept across the plains of North Dakota igniting coal seams.

Re: Steam Networks

#112

Post by wrsh07 »

glenstein wrote: post #88
imglorp wrote: post #30

The article cites end-to-end efficiency as 60%. Plus the costs of maintaining steam generators and the pipe network. Electrical transmission systems are roughly 85% efficient to the consumer; together with boring old resistive electric radiators which are 100% efficient. So is there any reason to subscribe to the steam system for new construction?

>Electrical transmission systems are roughly 85% efficient to the consumer; together with boring old resistive electric radiators which are 100% efficient. I'm wary of attempting comparisons of end to end efficiency, just because these aren't apple to apple comparisons. Solar panels are 20% efficient. Nuclear power can be anywhere between 60 and 90% efficient. Coal plants can be between 35 and 50% efficient. Each of…

Maybe this just makes your point, but solar panels being 20% efficient is about "how efficiently it converts energy from the sun into usable electricity"

All that matters is the actual power generation since there's no marginal utility of "what else we would use that space for" (unless you're consuming farmland etc for the solar panels)

Re: Steam Networks

#113

Post by wafflemaker »

abeppu wrote: post #85
dietr1ch wrote: post #45

Earlier quoted context omitted.

It also means that at the local scale it might be better to distribute steam. Think about future residential nuclear plants. It might not be worth investing into steam distribution on top of electrical as electrical is more flexible, but there might be steam that's residue otherwise that could be used on heating.

> future residential nuclear plants What does this mean? Are you imagining a future where individual houses have their own nuclear plants? Or where nuclear plant workers live on-site? I'm get the argument that we should have more nuclear power, and that some future reactors may be small, but I don't understand the expectation that they would be close enough to residences to pipe steam.

In many places in the world people don't live on ranches or in 1000 m² houses, but in 80-150 m² twin houses or even flats.

In such tighter conditions, you can easily have enough inhabitants per km² that it would justify building small mobile nuclear reactors.

Who would like to live next to a reactor if it can melt down? Well, you have reactors using fuel pellets locked in marbles that due to their diameter can never meltdown.

Re: Steam Networks

#114

Post by mschuster91 »

Fun fact: it's not just small grids that run on steam - Munich's steam heating dates back to 1908 and since 2022 it's being reworked at massive expense to hot water to better accommodate geothermal and other renewable forms of heatpump based generation because these sources cannot get hot enough to produce supercritical steam [1].

[1] https://www.swm.de/dam/doc/geschaeftskunden/fernwaerme/flyer...

Re: Steam Networks

#115

Post by dietr1ch »

abeppu wrote: post #85
dietr1ch wrote: post #45

Earlier quoted context omitted.

It also means that at the local scale it might be better to distribute steam. Think about future residential nuclear plants. It might not be worth investing into steam distribution on top of electrical as electrical is more flexible, but there might be steam that's residue otherwise that could be used on heating.

> future residential nuclear plants What does this mean? Are you imagining a future where individual houses have their own nuclear plants? Or where nuclear plant workers live on-site? I'm get the argument that we should have more nuclear power, and that some future reactors may be small, but I don't understand the expectation that they would be close enough to residences to pipe steam.

There has been a couple small scale nuclear power projects for a while now,

- https://newatlas.com/energy/oklo-aurora-nuclear-microreactor... - https://www.popularmechanics.com/science/a33896110/tiny-nucl... - https://www.nuscalepower.com/products/nuscale-power-module

They target from home to residential scale. I hope they are eventually a thing.

Re: Steam Networks

#116

Post by immibis »

riggsdk wrote: post #90
LeifCarrotson wrote: post #71

Earlier quoted context omitted.

Those electrical systems are about 85% efficient once the chemical energy in the coal has been converted to kinetic energy in the turbine. Losses in the generators themselves and in voltage loss through transformers and wires add up to about 15%. But they're only about 33% (old tech) to 45% (best-case new tech) efficient when it comes to thermal potential. Burning coal or natural gas produces lots of heat, and while…

Random thought: could you insulate high voltage wires in pipes and blow cold air through those? Any loss would become “free” heating for homes nearby.

The wire needs to be at least as hot as the desired temperature in the home.

Re: Steam Networks

#117

Post by immibis »

wrsh07 wrote: post #112
glenstein wrote: post #88

Earlier quoted context omitted.

>Electrical transmission systems are roughly 85% efficient to the consumer; together with boring old resistive electric radiators which are 100% efficient. I'm wary of attempting comparisons of end to end efficiency, just because these aren't apple to apple comparisons. Solar panels are 20% efficient. Nuclear power can be anywhere between 60 and 90% efficient. Coal plants can be between 35 and 50% efficient. Each of…

Maybe this just makes your point, but solar panels being 20% efficient is about "how efficiently it converts energy from the sun into usable electricity" All that matters is the actual power generation since there's no marginal utility of "what else we would use that space for" (unless you're consuming farmland etc for the solar panels)

Ah, but a thermal solar panel is more like 60% efficient, and it's built of glass, black spray paint and a garden hose. If the ultimate goal is to heat something with sunlight, you know which approach is the best. Several times as much area coated in special silicon stuff, or.... garden hose spray-painted black.

If the purposes are mixed, of course a photovoltaic panel can generate electricity for many purposes, while sunlight shining on a garden hose can only heat water. So it might be a more useful system, even more cost-effective, despite being much less thermally efficient.

It's the same with burning things to make heat, versus burning them for electricity and then using electric heaters.

Re: Steam Networks

#118

Post by tallanvor »

metadat wrote: post #15

How is mildew and mold avoided in the pipeline and interior spaces being heated by steam?

Mold doesn't grow well outside of around 60-80F (15-26C), and it needs food. Steam and hot water systems also use treated water to help reduce corrosion in pipes. That said, radiators themselves still do corrode and create nasty looking water even if it's generally sterile.

You should be more worried about Legionella, but proper steam and hot water systems will stay above 140F (60C) as that temperature not only prevents the bacteria from multiplying but will kill 90% of them within 2 minutes.

Re: Steam Networks

#119

Post by lxgr »

UltraSane wrote: post #102
lxgr wrote: post #29

My favorite fact about steam distribution systems is that they can be used for cooling, using either a steam-powered compressor or using adsorption refrigeration. At least the former seems to actually have been employed or at least studied as an option by ConEd in NYC: https://web.archive.org/web/20071008014254/http://www.coned....

adsorption refrigeration has a really bad coefficient of performance, typically 0.3 to 0.7, while vapor compression systems get 3-5

Ah, I was always wondering why they weren't more commonly used, but that's a pretty horrible coefficient of performance. I guess it's really only worth it if you want no moving parts for quiet or maintenance-free operation?

Re: Steam Networks

#120

Post by coryk135 »

jdwithit wrote: post #59
coryk135 wrote: post #25

This part really caught my attention: > in 1962, the anthracite seam under Centralia, PA – 25 miles to the west of Lehigh County – caught on fire and is still burning today.) That’s crazy to think that for over 60 years there’s been an underground coal mine on fire. I wonder how long the mines will burn for. The pictures on Google are quite interesting.

Yeah the Centralia story is wild. Who knows when the fire might ever go out? It's caught the imagination of many writers over the years, who have either been inspired by it or used it directly as a setting. Mostly in horror/paranormal content. As the Wikipedia entry notes "Centralia has been used as a model for many different fictional ghost towns and manifestations of Hell. Prominent examples include Dean Koontz's S…

I was thinking about that. It sounds like a great setting for a story but I felt like I’d seen it before and I guess this is why.
Post reply on HN