[HN Gopher] Steam Networks
___________________________________________________________________
Steam Networks
Author : herbertl
Score : 273 points
Date : 2025-03-13 14:37 UTC (8 hours ago)
(HTM) web link (worksinprogress.co)
(TXT) w3m dump (worksinprogress.co)
| 6stringmerc wrote:
| One of my three favorite books growing up is relevant to this
| article. It's also a great allegory about the passage of time and
| technology. Maybe worth picking up a copy...I still own mine:
|
| https://en.m.wikipedia.org/wiki/Mike_Mulligan_and_His_Steam_...
| pbronez wrote:
| Fantastic book, great recommendation.
| SirFatty wrote:
| It was read to me as a child, and I read it to both of my sons.
| It's one of the few things I have from my childhood.
| static_int wrote:
| Saas - Steam as a service
| ge96 wrote:
| Pocket steam
|
| (carries a nuclear pellet around) just add water
| jasonthorsness wrote:
| Even Seattle has one of these! And the University of Washington
| as well. It's amazing that the economics holds up even today.
|
| https://en.m.wikipedia.org/wiki/Seattle_Steam_Company
| walrus01 wrote:
| Vancouver as well:
|
| https://en.wikipedia.org/wiki/Creative_Energy
| kridsdale1 wrote:
| And UBC
| jihadjihad wrote:
| Indianapolis, too [0, 1]:
|
| > the second largest district steam system in the United
| States. The plant provides steam for heat and hot water to more
| than 200 commercial buildings and industries across downtown.
| Perry K's steam also helps power chilled water facilities which
| cool more than 60 large facilities around downtown. [1]
|
| I grew up going to downtown Indianapolis as a kid and was
| always freaked out by the steam emanating from the manholes and
| grates on the street. It turned out not to be an unfounded fear
| --they have occasionally exploded [2].
|
| 0: https://en.wikipedia.org/wiki/Perry_K._Generating_Station
|
| 1: https://info.citizensenergygroup.com/thermal/history
|
| 2: https://www.wfyi.org/news/articles/locking-covers-
| installed-...
| organsnyder wrote:
| Grand Rapids, MI, too: https://www.vicinityenergy.us/blog/our-
| history-vicinity-ener...
| taurath wrote:
| You can see the steam plant from pike place market and the
| steam stacks look like there's some sort of industrial thing
| going on which now looks very out of place. It was interesting
| to figure out what the building was for! The biggest customers
| are the hospitals up on the hill, and the steam is used to
| sterilize instruments alongside heating.
| 2OEH8eoCRo0 wrote:
| A lot of military bases have steam pipes all over the place. I
| think they recently demolished the Camp Lejeune steam plant
| strgrd wrote:
| Montpelier, Vermont as well: https://www.montpelier-
| vt.org/427/Project-Background
| UltraSane wrote:
| A LOT of universities have a central heat plant that pumps hot
| water to all the other buildings. I think steam has been phases
| out because it is so much more dangerous and electric pumps
| make it unnecessary.
| quickthrowman wrote:
| Yeah, a lot of institutions are removing steam for heating
| and replacing it with glycol loops.
| pbronez wrote:
| TIL that steam distribution was invented in the USA around 1880,
| and is still used in NYC. Never occurred to me that "Steam
| Plants" literally produce steam for distribution. I thought that
| was a glib reference to the white smoke they produce!
| martindbp wrote:
| Valve's "Steam" platform naming makes more sense from this
| perspective. Literally the pipes transporting games to
| customers.
| kraftman wrote:
| I was hoping this article would be about some crazy new
| networking inovation from Valve!
| T-zex wrote:
| I always thought watching films that steam in the dark streets
| was some cool 80s aesthetics. As in 'You are in this dark corner
| of the city where nobody can hear you' scary or edgy.
| triceratops wrote:
| It would be a shitty steam network that allowed steam to just
| leak.
| lxgr wrote:
| Steam rising out of manholes is definitely commonplace in
| NYC: [1]
|
| There's a stretch of sidewalk in the Financial District that
| gets so hot that you can feel it walking past on some days.
| And apparently, sometimes these things explode... [2]
|
| As far as I've heard it's not (all) actual leaks, though, but
| rather water dripping on the exterior of the hot pipes
| carrying the steam itself being evaporated.
|
| [1] https://en.wikipedia.org/wiki/New_York_City_steam_system
|
| [2] https://en.wikipedia.org/wiki/2007_New_York_City_steam_ex
| plo...
| vel0city wrote:
| It's often not the steam pipes leaking. The sewers are very
| humid and warmer than the air above. As the air convects up
| it hits the cold air and the humidity condenses. The same
| thing happens in lots of other cities when the weather is
| right.
|
| Maybe the steam pipes keeps the sewers warmer in places
| with steam but they should be well insulated in the end.
| harrison_clarke wrote:
| you can see it pretty often in NYC, coming up from
| vents/pipes in the road
|
| i don't think it's steam leaking. it's drainage/sewer water
| being heated by the steam system (and other heat sources down
| there) enough that it evaporates and rises up to the street,
| and then condenses into vapor/fog because the street level is
| cooler
| triceratops wrote:
| That's what I figured.
| LightHugger wrote:
| Then every city with a steam network is shitty! They bleed
| them with steamstacks all over the place.
|
| Apparently it's to regulate pressure.
| petee wrote:
| I grew up in a city without steam and the sewers would still
| smoke like that when it got cool out, like early morning; its
| still fairly warm down there
| wrenky wrote:
| I thought that too (but more New York Christmas Eve movie
| impressions) until I saw steam coming from manholes in Denver.
| Blew my mind that it was a real thing haha.
|
| In addition to the heating/cooling uses, the mint in Denver
| uses it to clean coins!
| maxwell wrote:
| Marsh Island, Maine as well:
|
| https://umaine.edu/umec
| pfdietz wrote:
| The temperature of this is such that industrial heat pumps are
| available to produce the steam. I don't imagine these are used in
| NY City, but they could be.
| metadat wrote:
| How is mildew and mold avoided in the pipeline and interior
| spaces being heated by steam?
| darknavi wrote:
| Pretty sure the steam is ran through radiators and not just
| dumped directly into the air.
| lxgr wrote:
| Part of it is definitely dumped directly into the air through
| an over-pressure valve on each radiator. At least that's been
| the case in all steam-heated NYC apartments I've ever visited
| or lived in.
|
| But what counteracts this is a loss in humidity caused by the
| heating of cold air from the radiator itself (cold air warmed
| up reduces relative humidity), and in my experience, this
| more than counteracts the little bit of steam hissing out of
| the radiator valve.
|
| As a side note, I've always wondered if the steam being
| vented that way is actually coming from the steam plant, or
| whether there's a heat exchanger somewhere in between that
| isolates a building's steam network from the distribution one
| (which is the case for liquid water heating, as far as I
| understand).
| mindslight wrote:
| nit: The valve is a thermostat that vents the air/steam in
| the radiator when it's not hot enough, letting new steam
| come in and replace it. This gets heat to the radiator
| quicker (over pure diffusion), and provides a mechanism of
| controlling its individual heat output. Of course, these
| valves are often broken.
| lxgr wrote:
| Interesting, that explains why it's going off so
| consistently and makes a lot more sense than just
| avoiding overpressurization. Thank you!
| dangerlibrary wrote:
| Super heated water is a pretty effective disinfectant within
| the pipes. For interior spaces ventilation is a legitimate
| problem in non-forced-air systems.
|
| Historically, you open a window.
| harrison_clarke wrote:
| if steam leaks out and gets trapped somewhere, presumably
| that's a breeding ground for mildew and mold
|
| inside the pipe, can much life survive? is there anything to
| eat in there? has anything evolved specifically to live in NYC
| steam pipes?
| tallanvor wrote:
| 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.
| fulafel wrote:
| Today's ConEd seems to lag environmentally on the generation
| side: still runs on fossil fuels, and only half of the steam is
| by cogeneration of heat and power. (Going by
| https://en.wikipedia.org/wiki/New_York_City_steam_system)
| MiscIdeaMaker99 wrote:
| Indianapolis also has a large steam network, with a prominent
| steam plant located in the southwest corner of downtown proper --
| just down the street from Lucas Oil Stadium.
|
| https://en.wikipedia.org/wiki/Perry_K._Generating_Station
| coryk135 wrote:
| 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.
| Peanuts99 wrote:
| There's Burning Mountain in Australia which has been burning
| for thousands of years.
| arrosenberg wrote:
| And a burning crater in Turkmenistan that's been going since
| the 70s.
| 725686 wrote:
| 6,000 years, according to Wikipeda. That is wild.
| jdwithit wrote:
| 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 Strange Highways and David
| Wellington's Vampire Zero."
| coryk135 wrote:
| 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.
| subpixel wrote:
| I've been there. It's where my ancestors are from, and an area
| of PA where all the jobs and civic like burned up long ago as
| well. Not a fun region.
| themaninthedark wrote:
| There is also Yanar Dagh in Azerbaijan.
|
| Wiki says the fire started in the 1950's but CNN says 4
| thousand years.
|
| https://en.wikipedia.org/wiki/Yanar_Dagh
| https://www.cnn.com/travel/article/yanar-dag-azerbaijan-land...
| toenail wrote:
| There's also one in Germany that's been burning since the 17th
| century, Goethe even visited and wrote about it,
| https://en.wikipedia.org/wiki/Brennender_Berg
| shagie wrote:
| 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.
| lxgr wrote:
| 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....
| Brian_K_White wrote:
| Similarly propane powered refridgerators.
| UltraSane wrote:
| adsorption refrigeration has a really bad coefficient of
| performance, typically 0.3 to 0.7, while vapor compression
| systems get 3-5
| lxgr wrote:
| 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?
| imglorp wrote:
| 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?
| exar0815 wrote:
| At least where I live, the Steam is either reused from thermal
| power plant waste heat which would be evaporated off anyways,
| or its the heat directly produced from specialised combined
| electric/thermal gas plants (Blockheizkraftwerk). Also, general
| industrial waste heat is sometimes used (glass plants e.g).
| someuser2345 wrote:
| Most electricity is generated by using steam to turn turbines,
| right? So it definitely seems more efficient to just use the
| steam directly, instead of converting it to electrical energy
| and then converting it back to heat.
| proee wrote:
| Except you can ONLY use steam for heating and transporting it
| over distance is not efficient. If you turn steam into
| electricity you can use it for ANYTHING and transport it over
| long distances efficiently.
| dietr1ch wrote:
| 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.
| abeppu wrote:
| > 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.
| wafflemaker wrote:
| 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.
| dietr1ch wrote:
| 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.
| vdnkh wrote:
| Steam in NYC is also used for cooling
| https://en.wikipedia.org/wiki/New_York_City_steam_system
| perihelions wrote:
| That reasoning isn't enough on its own, because on the
| clients' end, electric heat pumps can be more efficient than
| direct steam heating. Actually their "efficiency" is far
| above 100%,
|
| https://en.wikipedia.org/wiki/Coefficient_of_performance
| virtue3 wrote:
| And their efficiency plummets starting at 40F and below.
| nebolo wrote:
| The efficiency of modern cold-climate heat pumps plummets
| to 200-300% at 40F and perhaps 175% at 5F.
| Brian_K_White wrote:
| But 5f is still high.
|
| This is actually terrible and supports their point. Heat
| pumps are not sized as if they were running at a mere
| 100% or less, they are sized for the btus they normally
| produce, and aim to run close to 100% of the time,
| meaning they will be too small and not be able to do the
| job when they drop below 200-300% efficiency, unless they
| are grossly oversized. That leads to short cycles which
| makes condensation and moisture in the summer and wear
| and tear all year and less electrical efficiency because
| starting a pump and blower costs more than running it.
|
| Current inverter types that can run slow do allow them to
| be oversized but it's still not great. Those are more
| expensive and have more failure points in electronics
| too.
| whatevaa wrote:
| So at -20 and below they are basically very, very
| expensive resistive heaters. Good for medium climates,
| bad further north.
|
| Also either need very expensive oversizing or backup heat
| sources to compensate reduced heat output, even if you
| get occasional cold spikes.
|
| Unfortunately nothing in life is as simple as it first
| seems.
| jacobaul wrote:
| Here is a great Technology Connections video which lays
| out why the sizing issue might not be as bad as you're
| thinking. The gist is that many people are steered away
| from heat pumps (or sold very expensive oversized units)
| by outdated industry thinking which vastly overestimates
| load calculations.
|
| I won't try to make his case here, but he is pretty
| convincing that a reasonably sized heat pump system can
| be sufficient even in very cold climates (by US
| standards).
|
| https://youtu.be/DTsQjiPlksA
| whatevaa wrote:
| It's all theoretical. In real life, retrofitting heat
| pumps into exisinting homes is a bit different, as those
| homes are neither made for air heat sources (at least in
| my region), nor they are insullated well. You might say,
| dough, insulate it, but it is easier said than done, as a
| lot of those old homes relied on their leakage for
| ventilation, not to mention that is very expensive
| investment (much more expensive than the heat pump
| itself).
|
| I would reccommend keeping backup heat source when
| installing heat pumps into older homes. A simple wood
| stove, used during cold spikes, could be enough.
|
| My country has subsidies for heat pump installations into
| older homes and it had requirement to get rid of chimneys
| to get that. After the whole europe energy crisis thing,
| this requirement is gone now. Turns out having
| alternatives is a good thing :)
| eldaisfish wrote:
| I live in Canada in an older home with terrible
| insulation.
|
| Out two tonne heat pump works just fine even at -25C this
| past winter.
|
| We still have a natural gas furnace but our gas usage is
| down 65% despite this winter being colder than last
| year's.
|
| Tell me again how heat pumps don't work in colder
| climates?
| bluGill wrote:
| This is why I opposed historical designations. Most old
| buildings are obsolete and need to be destroyed. There
| are only a tiny number of buildings that are really
| historic, sure save them, but the vast majority are just
| old and need to be knocked down for something better. If
| it isn't taught in history class then it isn't historic.
|
| It is easy to see the loss of something old. However the
| opportunity cost from not building new is something that
| is very hard to get people to understand.
| HelloMcFly wrote:
| This is not theoretical: my heat pump purchased in 2021
| worked well for four straight days of below 0F. Kept our
| temp at 68 inside. We live in an old home from 1917 with
| poor insulation between the brick exterior walls and
| drywall.
| nightpool wrote:
| How often does it get to -20f in New York City?
| whatevaa wrote:
| Ahh damn, I forgot unit, I meant -20C, so -4F
| Loudergood wrote:
| You have to go quite far north for -20F to become
| frequent.
| bluGill wrote:
| If it EVER gets to -20 that is what matters. You need to
| prepare for the worst case weather, not the common ones.
| brnt wrote:
| 1990s called, they want their efficiency back ;)
|
| Sure, you can still find good weather heat pump that crap
| their pants near or under freezing. However, the majority
| sold here in Europe still stay well of 200% down to -15C,
| some even -25C.
| smadge wrote:
| "Fifth generation" district heating uses heat pumps to
| extract heat from a network of lukewarm water.
| m4rtink wrote:
| Yep and IIRC you can even dump waste heat back to the
| loop at what would normally be just consumers - eq. to
| cool a hockey stadium or for a big building AC system.
| a1371 wrote:
| That's not true. Except for nuclear and solar collectors, all
| renewables, especially hydro, have nothing to do with steam.
| outworlder wrote:
| What isn't true?
|
| > Most electricity is generated by using steam to turn
| turbines
|
| That is true. It is also true that renewables usually do
| not use steam. But they don't answer for "most
| electricity". That's natural gas, coal and other types of
| thermal plants, including nuclear.
| bluGill wrote:
| Renewable power is 30% of the world grid.
|
| Gas combined cycle power plants get part of their power
| from gas in the turbine directly, and part of it from
| steam cycles. I can't figure out what % over of power
| comes from which part, and not all gas power plants are
| combined cycled.
|
| It seems reasonable to say that most electricity is not
| generated by steam turbines. However I'm not sure how to
| find the real data to verify this. (and pedantically the
| gas in a gas turbine is mostly steam)
| kibwen wrote:
| Geothermal plants also use steam (not to be confused with
| geothermal heating/cooling, which is just a heat pump with
| the heat exchanger underground rather than in the air).
| bluGill wrote:
| Where I live most electricity is generated from wind. Solar
| also has a large share of some grids. Your location may be
| different but it should have a significant renewable share by
| now.
| paxys wrote:
| There's no single efficienty number for "steam". Steam
| turbines in large power plants for example are >90% efficient
| when considering just the thermodynamics. There are a hundred
| other variables involved.
| m4rtink wrote:
| I'll note that powerplant steam turbines are often pretty
| cutting edge & supported by essentially a special plant to
| achieve this levels of efficiency and reliability. Stuff
| like _hydrogen cooling_ the generator bit:
|
| https://en.wikipedia.org/wiki/Hydrogen-
| cooled_turbo_generato...
| mikepurvis wrote:
| I believe in the NYC case, the steam is also not right off
| the reactor-- it's waste steam that has already been through
| a turbine and so is still hot and under some amount of
| pressure, but is no longer economically valuable in a power
| plant context. So it's run into the city as an alternative to
| just venting it into the atmosphere.
| walrus01 wrote:
| In terms of thermodynamics, a electric resistive heater is 100%
| efficient, but if the measurement is how many BTU of heating
| you can put into a room in a day with a certain amount of watt
| hours, a modern heat pump will always beat it. Also of course
| 100% electric.
| graemep wrote:
| A heat pump is more than 100% efficient on that measure.
|
| I am not sure about "always". Does it not depend on the
| temperature difference?
|
| The use cases for steam seem to be where you need more than
| room heating though: the first paragraph mentions sterilising
| medical equipment, humidity control, and washing.
| walrus01 wrote:
| My understanding is that it varies by temperature
| difference, but there's specialized series of heat pumps
| which work "okay" with very cold outside temperatures, even
| down to -25C, which are becoming popular to replace oil
| tank heating systems in Atlantic Canada. Apparently even
| when operating at -20C outside air they're still more
| efficient than electric baseboard heating.
|
| I don't know of any of the customers of the steam system in
| downtown Vancouver that use it for sterilization purposes,
| it connects almost exclusively large office towers. There's
| no hospital or medical facilities connected to it.
| bng8 wrote:
| Most energy is generated from steam that has a terrible
| efficiency of 40%
| jsiepkes wrote:
| > Electrical transmission systems are roughly 85% efficient to
| the consumer;
|
| Electrical generation itself isn't a 100% efficient. For
| example a gas powered electricity plant is about 60% efficient
| for generating electricity. Generating heat from gas is far
| more efficient.
|
| Then again if you use the electricity not for direct heating
| but for example to power a heatpump on the other end (i.e. you
| use the electricity to extract heat from the air) then it could
| be more efficient.
| perihelions wrote:
| Yes: very low temperature steam is useless from a thermodynamic
| perspective, cannot be used to perform (meaningful amounts of)
| work or generate electricity. When sourced a waste byproduct of
| an electric power plant, it's essentially free--it has no other
| economic value.
|
| There's zero opportunity cost of "you could use it for some
| other purpose instead".
| pjc50 wrote:
| Sadly this article doesn't make it clear whether it's waste
| steam from electricity generation or steam made explicitly
| for this purpose. It also doesn't specify what the fuel is
| now - it used to be coal, is that still the case?
|
| Wikipedia says "Approximately 30% of the ConEd steam system's
| installed capacity and 50% of the annual steam generated
| comes from cogeneration" i.e waste steam, which is .. half
| good, I suppose.
|
| It also gives https://web.archive.org/web/20101207021857/http
| ://coned.com/... which I guess has the rest of the details
| in.
| bluGill wrote:
| There is cost though - the pipes needed to get steam
| someplace are not free. Those pipes can explode when things
| go wrong so people can die. How you add those costs up is a
| debatable question, but it isn't free.
| bob1029 wrote:
| https://en.wikipedia.org/wiki/Cogeneration
| jszymborski wrote:
| Not my expertise, but my understanding is that district heating
| is a very very efficient way to store electricity, such that
| the inefficiencies in transmission are mitigated in part by the
| storage efficiency. This allows you to more reliably depend on
| energy sources that don't have 100% uptime.
|
| That said, I think most of this applies to heated water, not
| steam.
| LeifCarrotson wrote:
| 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 some of
| that heat turns the turbine, there's still a lot left that gets
| lost to the condenser or to the exhaust flue and atmosphere.
|
| However, that's where steam distribution is awesome: It enables
| cogeneration, where some of the waste heat from electricity
| production can be efficiently used by heating industries. The
| electrical plant requires supercritical steam at 1000F and 1000
| PSI, but the steam network only needs steam at ~150 PSI and
| 350F, which still has a lot of energy in it from the burners
| but is of comparatively little use to the turbine.
| riggsdk wrote:
| 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.
| z2 wrote:
| I feel like this could be a nice high school physics test
| question. Realistically, I don't think HV lines have much
| energy loss, owing to the use of high voltage in the first
| place as a means of minimizing loss. Then there are
| considerations for air resistance in the tubes, an almost
| 100% effective insulator, and all those real world issues
| of gnarly general maintenance.
|
| Almost all electricity run through computers are basically
| resistance losses at the end of the day, so data centers
| and crypto miners on the other hand...
| lucb1e wrote:
| Could not find the answer, kept getting general pages
| about how much current a wire can pass (without the
| result even containing the keyword I looked for, like
| temperature or heat or warm). To still have _some_
| indication of whether this is an interesting thing to
| keep looking into, ChatGPT says:
|
| > Typically, high-voltage transmission lines are designed
| to operate at temperatures of around 75 to 100degC (167
| to 212degF). However, under heavy loads, they can
| sometimes reach up to 150degC (302degF), but this is
| usually the upper limit for safe operation.
|
| If that's a core temperature then the insulation might
| not make it significant, but if the outside leaks this
| much... I might not mind paying myself for a plastic tube
| and a fan to use around the line if I lived near one.
| Okay okay, it'll be more complicated than that, but
| still: free energy? And you're doing the power company a
| favor by decreasing the resistance in the case of most
| metals (https://www.engineeringtoolbox.com/resistivity-
| conductivity-...) including copper which
| https://en.wikipedia.org/wiki/High-voltage_cable says
| they're made of
| immibis wrote:
| The wire needs to be at least as hot as the desired
| temperature in the home.
| vkazanov wrote:
| There's also a hybrid approach: generate electricity and also
| reuse heat for centralised heating. This can reach 60%
| efficiency as far as I remember but might require building
| plants closer to heat consumers.
| vkazanov wrote:
| Just noticed that this is what you suggested :-)
| 8ig8 wrote:
| Cogeneration
|
| https://en.wikipedia.org/wiki/Cogeneration
| m4rtink wrote:
| Isn't it actually like (100% - tranfer loses) efficiency ?
|
| In modern co-generation you can for example burn gas in a
| gas turbine & produce electricity. Then heat water to steam
| with the gas turbine exhaust & power a steam turbine to get
| more electricity. And then the steam is condensed by the
| district heating water loop.
|
| So in theory you will get more electricity & almost all the
| "waste" heat is used to heat houses.
| nine_k wrote:
| In most places with district heating, the heat that goes to the
| heating system is waste heat which turbines of a nearby power
| plant cannot use. This applies to fuel-fired and nuclear power
| plants alike. (Keywords: Carnot cycle efficiency.)
|
| So using electricity for heating would be just throwing free
| heat away. Heat distribution networks are of course not free
| though.
|
| Electric heating would be an economical win if the electricity
| could be harvested by solar and wind generators, and stored.
| Storing solar heat directly is much trickier.
| calaphos wrote:
| It's not quite waste heat because the cold side of thermal
| power plants wants to be colder than district heating
| temperatures for best efficiency. There is some loss in
| electrical efficiency compared to non cogeneration plants,
| but the combined efficiency is a lot higher.
| hwillis wrote:
| > Usage fees are then added on top, paying anywhere from $11.35
| per megapound in the summer to $35.013 during peak season.
|
| Steam with <1112 BTUs per pound vs room temperature will
| condense, so the heat value of a megapound of steam is at least
| 325,895 kWh. That's a marginal cost of 1 cent to 3 cents per
| MMBtu or 3.5 cents to 11 cents per MWh. The hookup cost
| ($3,555) is much smaller than the cost of the steam ($13k-$44k
| per the article).
|
| For comparison natural gas costs a couple dollars per MMBtu and
| wholesale electricity costs $40-$60 per MWh. *The steam is
| orders of magnitude cheaper.*
|
| If the article's quoted prices are accurate (note: Lincoln
| Towers seems to pay $2.43 per megapound, significantly less
| than the $11.35 usage fee the article gives immediately before.
| Not sure what's up.) then steam is practically free. I'm not
| really sure how that's possible; maybe there are subsidies or
| regulations enforcing production. A significant amount of the
| steam is from cogeneration, where steam is a byproduct of
| pollution-reducing processes- it makes sense that would reduce
| the cost, almost all steam would need to be a byproduct to
| explain the price.
| glenstein wrote:
| >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 these can have an economic rationale despite
| these differences in efficiency.. A Dyson sphere with 0.001%
| efficiency could be a winning value proposition. Granted, these
| are energy sources rather than transmission infrastructure, but
| the point is the same.
|
| I would want to know about the efficiency loss from whatever
| primary source of energy was generated before it gets
| transmitted across the electrical transmission infrastructure,
| and I would want to know how it compares to a steam source,
| which could plausibly be such a thing as waste heat. If your
| steam is cheap or potentially even free it could conceivably
| win out in the final assessment, even if it has higher relative
| transmission losses.
| wrsh07 wrote:
| 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)
| immibis wrote:
| 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.
| glenstein wrote:
| Right. And the same with electrical energy transmission
| for the purpose of delivering heat compared vs steam
| infrastructure.
| cship2 wrote:
| Steam is Carrington event resistant not electric system.
| tracker1 wrote:
| Where/how is the electricity sourced in a given case is
| probably worth consideration. If you have alternative sources
| for generation of steam vs generation of electricity, the
| methods/approach may vary. Not to mention the impact of the
| equipment necessary, the build process, availability and
| dependency on supply lines should all be considered.
| MisterTea wrote:
| Pratt university in Brooklyn used to have a gentleman working
| there named Conrad Milster. He is a steam head and machinist who
| maintaining Pratts secret "working museum", a turn of the century
| steam generating plant for the campus. The plant also features
| two boilers, the original boiler which originally provided both
| heat and power and an additional boiler was added in the 30's to
| add capacity as the campus expanded. Milster also lived on campus
| in the old row houses. His was special, a full set of gauges and
| meters in his living room was plumbed to the plant so he could
| keep an eye on the boilers from he comfort of his home. He also
| said that steam from the plant not only heated the campus but a
| few buildings off campus that surrounded it. I never got to ask
| which buildings though. So there very well might be a little
| steam network in Brooklyn around Pratt.
|
| This is located in the basement of one of the buildings on
| campus. The power plant consists of three Ames Iron works single
| piston steam generators producing 120V DC fed to a marble switch
| board. Another piece is an early non-functioning steam turbine DC
| generator, WW2 era diesel generator from a battle ship. A 30HP
| motor-generator set used to provide 120V DC to the two service
| elevators in the building. And in the boiler room are numerous
| antique yet still functioning feed water pumps (the original
| steam driven feed water pumps actually do most of the work with
| newer electric pumps kept for standby) On the wall of the boiler
| room is a functional steam driven Ingersoll Rand air compressor.
| Amazing place. When I first visited in the 90's the MG set was
| still running providing power to the service elevators though
| they were replaced in the 00's leaving the MG set idle. There is
| also an old giant wood and brass Master clock in the office that
| was wired to every other clock on campus so whatever time you set
| on the master, the other clocks would then run super fact until
| they come around to the set time. It was running up to the 80's I
| think but Milster said a renovation crew hacked up all the wiring
| and no one ever bothered to fix it.
|
| Milster was fired a few years ago supposedly after he refused to
| remove the resident stray cats who lived in the plant (they even
| had their own little decorated doorway.) The reason being a union
| employee was allergic to the cats and kept complaining until they
| fired him. Shame because anyone who works with antique steam
| equipment knows Milster and hes full of ancient knowledge no one
| will ever regain.
|
| Edit: If you are into steam then look up Conrad Milster. I had
| the pleasure of talking to him a few times and he's such a nice
| and knowledgeable individual. He even started one of the 120V
| generators just for me after I said "Wish I could see it run" and
| he was like "sure" then opens a valve and slowly opens another to
| get it up to speed. Scary as the inertial lever arm bangs around
| loudly in the flywheel but then its goes near silent and hums
| away. Steam engines are very quiet.
| blackeyeblitzar wrote:
| > The last total system failure was in 2007, when an 82-year-old
| pipe at 41st and Lexington exploded, showering Midtown in debris.
| Heavy rainfall had cooled the pipes, producing large amounts of
| condensate quickly, and a clogged steam trap meant that the
| system was unable to expel the water. When this build-up hit a
| critical level, the internal pressure shot up, causing the
| explosion. Almost fifty people were injured, and one woman died
| of a heart attack while fleeing
|
| The photo of this explosion makes it look huge. I wonder how much
| the pent up infrastructure work to avoid these issues would cost.
| Are water or gas pipes also vulnerable to this sort of thing?
| kibwen wrote:
| _> I wonder how much the pent up infrastructure work to avoid
| these issues would cost._
|
| The cost is essentially incalculable. Back in the 1800s people
| kept poor records of what they were stuffing under the streets,
| and the records that were kept were lost, and the ones that
| weren't lost are sitting in a box who knows where. NYC has
| effectively no idea what they're going to find under a street
| every time they tear one up, and the deeper you dig, the more
| you find.
| bluGill wrote:
| Compressed gasses are worse than fluids. I'm not sure if a
| water pipe even can explode - as soon as the pipe shatters
| there is no more energy as the water isn't going to expand.
| Gases will expand in the explosion and drive the pipe parts to
| more energy.
|
| That isn't to say water/fluids are not dangerous. They can
| kill. However for the same pressure gases are much worse.
| jabl wrote:
| The city where I live has a district heating system using
| water, the temp in the mains is up to 130C or thereabouts.
| Occasionally there are failures, but they tend to be fairly
| undramatic. Due to the temperature the water flashes to steam
| when released. It's not recommended to go too close to the
| leak due to the risk of scalding from the hot water and
| steam. But no explosions like can happen with a hydraulic
| block in a steam system.
| strgrd wrote:
| How common are district heating systems? Montpelier in Vermont
| uses wood stoves to deliver steam to a large part of their small
| downtown: https://www.montpelier-vt.org/427/Project-Background
| quickthrowman wrote:
| I live in Minnesota and both Minneapolis and St Paul have
| district heating and cooling systems in their downtown core
| areas. Cordia Energy operates the Mpls network and Evergreen
| Energy operates the St Paul network. I'm unsure what the fuel
| source is for the Mpls network but the St Paul network uses
| wood chips/wood waste and natural gas.
|
| Minneapolis: https://cordiaenergy.com/our-networks/minneapolis/
|
| St Paul: https://www.districtenergy.com/
| xattt wrote:
| Charlottetown, a city of 38,000, has a waste-to-steam plant
| that heats the hospital, downtown and the university.
|
| The 30-year-old steam network springs leaks every so often, so
| you see gurgling hot springs from the ground.
|
| I'd love to know how much cheaper it would be to use this form
| of heating for my home compared to oil heat.
|
| (1) https://www.enwave.com/locations/pei.htm
| realityking wrote:
| Incredibly common in continental Europe. Wikipedia has an
| overview: https://en.m.wikipedia.org/wiki/District_heating
| m4rtink wrote:
| Yep, we have a big distric heating system here in Brno, Czech
| Republic - in operation since 1930, with 110 000 housholds &
| most big public and commercial buildings connected. It
| started as coal fired, but the modern system combines natural
| gas cogeneration (gas turbine -> steam turbine -> district
| heat) and waste incineration (that also includes a steam
| turbine to make some electricity). In the summer the waste
| incinerator provides all the necessary heat for the system
| alone. :)
|
| Eventually the city would like to make the system stop using
| natural gas, so there is a wood waste burning plant comming
| online at the end of this year & hot water pipeline is being
| built from the nearby Dukovany power plant. This two together
| should make the system natural gas indepedent in the future.
| :)
|
| While it started as steam based system & powered most of then
| very important textile industry, steam also has issues. Old
| pipes loose quite a bit of heat on the way (there used to be
| evergreen meadows even in winter in places above the old
| steam pipes), the pipes flex quite a bit when heating
| up/cooling, so they need to be placed on rollers in
| underground channels with U shaped sections to account for
| the pipe stretching/contracting. The steam also condenses &
| you need to get rid of that condensate on the way. And while
| unlikely, it is possible for a steam pipe to burst/explode,
| which is very dangerous for any bystanders.
|
| For these reasons & because the textile industry being much
| less important, the Brno district heating system is being
| converted to hot water distribution, which is quite a bit
| more effcient apparently. Reportedly, with modern insulated
| pipes, the heat loss on the way is negligeable, the pipes can
| be placed directly in the ground & they form a closed loop -
| no more mucking with rollers, condensante or explosions.
|
| So in a few years, the often seen steam ventilation pipes
| (from the various steam related texhnical spaces) around the
| city will be a thing of the past. :)
| UltraSane wrote:
| The Shoreham Nuclear Power Plant was built between 1973 and 1984
| by the Long Island Lighting Company (LILCO) at a cost of
| approximately $6 billion. It was never put into use and was fully
| torn down in 1994. It stands as one of the most expensive
| industrial projects ever completed but never used for its
| intended purpose.
| jabl wrote:
| There's an interesting lecture about the New York city steam
| heating system by Dan Holohan at
| https://m.youtube.com/watch?v=nkgM0qCy5o4
| mschuster91 wrote:
| 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...
| MattGrommes wrote:
| Growing up in Southern California and New Mexico, the first
| exposure I had to systems like this was in Cities Skylines. It
| boggled my mind that this type of thing was still used enough to
| feature in a modern simulator game until I started researching
| them and found them to be a great solution. Very interesting
| article.
| AceJohnny2 wrote:
| Related: "The Lost Art of Steam Heating" by Dan Holohan (2017)
|
| https://news.ycombinator.com/item?id=18430512 (2018)
|
| Holohan argues that we've mostly lost competence at maintaining
| steam heating systems, and it's not that hard. The lack of
| understanding has led to many expensive and ineffective
| refurbishments.
| dylan604 wrote:
| "A recent study found that a fireplace pumps out 58 milligrams of
| particles under 2.5 microns in diameter (PM2.5s) per kilogram of
| firewood burnt. This means that every hour you spend in a room
| with a fireplace burning wood reduces your lifespan by about 18
| minutes, equivalent to smoking 1.5 cigarettes"
|
| These kinds of stats really irritate me. Sure, smoking isn't
| great. Breathing in small particulates also isn't great. However,
| the 18 minutes is such a weird thing. There are so many people
| that have lived longer lives by smoking than people that work out
| all the time. There's just no real evidence this stat is true.
| You can't clone a person and sit one clone in the room with a
| fireplace, and then the other not in the room. Then watch which
| one dies first.
|
| The only test I've seen with evidence of one doing something the
| other doesn't was the twin brother astronauts where one went to
| space and the other did not.
| lucb1e wrote:
| That's why they don't look at 1 person but at aggregates. If
| the world was made of twins and triplets and they lived
| identical lives (nutrition, stress levels, air quality, ...)
| besides the 1 factor you're interested in (fireplace yes/no),
| that would be great for learning from, but of course that's not
| the case, not even for that astronaut
|
| I'd encourage you to open up one of these studies. The language
| in scientific papers is made to sound smart but it's still
| English (most of the time) and you'll see these sorts of things
| are established by looking at many people in many situations
| and then use maths to tease out how much each of the factors
| (living near a major road, for instance) contributes to the
| thing being investigated (such as longevity). Many of the
| factors, also depending on the number of people involved, will
| not turn out to be statistically significant, meaning that the
| error margins are too large to be sure. For smoking and
| woodfire particulates though, we're certain that it's unhealthy
| to within extremely low error margins. Whether that's precisely
| 18 minutes: probably not, but presumably that's our best guess,
| even if it has uncertainty associated with it. The paper is
| linked literally within the quote you gave, if you want to
| check how certain they are about this:
| https://www.sciencedirect.com/science/article/pii/S235271022...
|
| Skimming this one, they didn't establish the relation between
| particulate matter and lifespan themselves but they cite other
| studies that did this:
|
| > correlating average PM2.5 levels during a shorter time
| interval and the average life expectancy during that same time
| period. In Taiwan, this method used data from 17 counties for
| the 2010 to 2017 period and resulted in a DLE factor of 0.798
| years per 10 mg/m3-increase in exposure to PM2.5 [50]. Using
| data from 545 counties in the United States for between 2000
| and 2007 [51] and data from 214 cities in China for between
| 2013 and 2017 [52], resulted in lower DLE factors: 0.14 and
| 0.18 years, respectively, per additional 10 mg/m3 of exposure
| to PM2.5.
|
| If you doubt those methods, you should click through to sources
| 50, 51, and 52. This study just measured the amount of PM2.5 in
| three situations and then multiplied it with that value from
| the other studies (I didn't read far enough to see which one
| they ended up picking, that should be mentioned somewhere if
| you want to know/check it precisely)
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