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Steam Networks

worksinprogress.co

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Re: Steam Networks

#121

Post by glenstein »

immibis wrote: post #117
wrsh07 wrote: post #112

Earlier quoted context omitted.

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, whil…

Right. And the same with electrical energy transmission for the purpose of delivering heat compared vs steam infrastructure.

Re: Steam Networks

#122

Post by cship2 »

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?

Steam is Carrington event resistant not electric system.

Re: Steam Networks

#123

Post by smadge »

perihelions wrote: post #42
someuser2345 wrote: post #33

Earlier quoted context omitted.

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.

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

“Fifth generation” district heating uses heat pumps to extract heat from a network of lukewarm water.

Re: Steam Networks

#124

Post by calaphos »

nine_k wrote: post #81
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?

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…

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.

Re: Steam Networks

#125

Post by tracker1 »

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?

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.

Re: Steam Networks

#126

Post by realityking »

strgrd wrote: post #78

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

Incredibly common in continental Europe. Wikipedia has an overview: https://en.m.wikipedia.org/wiki/District_heating

Re: Steam Networks

#127

Post by MattGrommes »

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.

Re: Steam Networks

#128

Post by AceJohnny2 »

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.

Re: Steam Networks

#129

Post by m4rtink »

vkazanov wrote: post #105
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…

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.

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.

Re: Steam Networks

#130

Post by dylan604 »

"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.

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