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#276 2023-06-17 07:07:34

Terraformer
Member
From: Ceres
Registered: 2007-08-27
Posts: 3,818
Website

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

We had a thing in town today about green energy and suchlike, so I was able to speak to people from the county council and town council about shared loop ground source heating.

Turns out, a village fairly close to us is already doing it -- https://www.chippingcommunityenergy.co. … gy-project

The two town councillors I spoke to are onboard with the idea (as expected), so I think local government support at all levels is there for such a scheme. And with other places already doing it, we wouldn't have to figure everything out ourselves.

We recently had elections too, so both town and city councillors have four years ahead they can focus on projects before having to worry about being replaced. That's enough time to get things done.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#277 2023-06-17 07:56:02

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,910

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Thanks for sharing the community link to the project of stored heat being made use of with heat pumps.

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#278 2023-06-17 09:09:00

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,219

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

For Terraformer re #276

Bravo! to all concerned!

Thanks for this encouraging report!


There is an opportunity for you to take part in the early phases of what would become a major effort by your community.  Please keep us informed as you watch the process.  If you give it a shove here or there, perhaps no one else will notice, but we can follow along if you tell us about it.

(th)

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#279 2023-06-20 17:15:01

tahanson43206
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Registered: 2018-04-27
Posts: 17,219

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Here is a link to a report on geothermal energy ...

https://www.yahoo.com/finance/news/deep … 00415.html

(th)

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#280 2023-06-20 19:26:29

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,910

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

3-mile depth for a company in the drilling business is not a huge expense but to the average person or town its going to be millions to achieve.

update

https://hybridupgrade.wordpress.com/

How to Turn an Air-conditioner Into a Heat Pump

https://highperformancehvac.com/convert … heat-pump/

it appears that with a double throw switch you can reverse the direction of the flow of the compression that makes heat not cold.

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#281 2023-06-20 20:11:37

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,219

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

For SpaceNut re #280

Thanks for noting the link in #279!

A source of energy that costs nothing after the initial investment sounds like a good investment to me.

If you invest millions in 2023, and reap the harvest for thousands of years, then the dividends start coming in immediately, and they increase in value with inflation as time passes.

A wise investor would carefully consider a prospectus like that.

(th)

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#282 2023-06-22 09:12:50

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

This is very good news!

The notion of accumulation applies here, I believe.  As long as you keep the book burners at bay, your accumulation of knowledge of methods should keep expanding.  So your library of references can expand.  But as GW has at times said, perhaps the "Art" may be harder to preserve, the "Art of Technology" that is.

So, we have to be careful who we permit to control the libraries.  Book burners are the worst.  But of course, in order to maintain "Best Practices" suggestions from library need to emphasize the regenerative and not degenerative hypnosis.

Hypnosis is said to only be suggestion.

So, the suggestion of advances in geothermal and geostorage are good things as far as I can see.  We want a prosperous population not an anemic one, which can be misused by psychopaths in positions of social power.

Done.


Done.

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#283 2023-07-31 10:49:45

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

A query such as "Elon Musk, Heat Pumps" brings up some information of value.

https://www.bing.com/search?q=%22Elon+M … 6f9c5d640c

I have seen talk associated with him of heat pumps that might get up as high on output of heat of 500 degrees C.

Also, some mention of seasonal thermal storage in sand and such.

Done.

Last edited by Void (2023-07-31 10:50:45)


Done.

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#284 2023-07-31 11:15:20

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,434

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Void wrote:

A query such as "Elon Musk, Heat Pumps" brings up some information of value.

https://www.bing.com/search?q=%22Elon+M … 6f9c5d640c

I have seen talk associated with him of heat pumps that might get up as high on output of heat of 500 degrees C.

Also, some mention of seasonal thermal storage in sand and such.

Done.

Any mechanical pump has losses due to friction and thermal leakage.  Also, temperature gradients are needed in order for heat exchangers to work.  To achieve high round trip efficiency, high storage energy density and high power density of the prime mover, the temperature difference between hot and cold source should be maximised.  Then again, the COP of a heat pump pumping from 300K to 800K, will not be much greater than unity.  This suggests that an electrical heating element might be a better hot source than a heat pump.


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#285 2023-08-01 06:55:09

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

I see your point on finding the actual limits of the product in the real world.

As for heating homes, that seems to be having some practical results, as you don't need 800 K.

But a factor that many may not look at for home heating is the increased load on the electric grid.  I have read articles that suggest that of each electric cars, and heat pumps for homes, about 22-23% of Carbon might be retired for each, in an ideal world.  But the heat pump achievements are to be for a much lower cost.

The article that excited me about industrial heat going up to 500 C, presumed a higher waste heat source than 300K, so maybe there could be some situations for that.  They presumed that about 1/2 of industrial heat could involve a heat pump, somehow.

And yes, I am aware that many think that there will not be enough materials for the "Green Energy" transition, and I do not dispute that that could be likely.  I don't want to raise blood pressures about that particular argument.

I might suggest that if you had an Eavor geothermal well however, perhaps with a heat pump you might have a practical source of industrial level heat, perhaps up to 500 C or 800K.  https://www.eavor.com/

And yes, all of this is iffy.  Reality bites actually but seeking may occasionally provide something of value to try for.

The aim being a glass partly filled, as only fairytales have a perfect ease to plenty.

Done

Last edited by Void (2023-08-01 07:06:39)


Done.

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#286 2023-08-01 09:48:09

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,431

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Void,

I don't get the sense that any of the people making wildly rosy predictions about what one technology might do versus another, have ever done any serious math to validate the underlying feasibility of their plans.  In fact, I think questions like that are purposefully ignored, because it tends to invalidate their rose-tinted view of their own technology, and probably tempers expectations from investors.

There's a lot to like about Eavor's technology, but they misdirect repeatedly on their own website, which makes no sense if you want more investment dollars.  They claim on their website that they don't use water.  In their video, located on the same page stating they don't use any water, they claim they use a propriety working fluid (without specifying what that working fluid is) in a closed loop system.  In the FAQ section of their website, they then plainly state that their working fluid is water.

Flat-out tell people you're using purified water in a closed loop, no different than any other geared steam turbine on the planet.  This should be a selling point, not something you obfuscate in weird ways.

1. We used oil well directional drilling technology to create a giant geothermal radiator array underground to soak up heat.

2. We use that heat to boil water, same as any other coal or nuclear or fuel oil power plant, and then we use the steam to drive turbo-electric generators to produce electrical power.

3. Since our technology works the same way as those other power plants, but doesn't burn anything, it's operating 100% of the time.  A wind or photovoltaic power plant only operates when it's windy or sunny outside, it requires an enormous land area to collect a lot of power, it consumes an enormous amount of energy-intensive material, and it doesn't last very long.  We don't have any good ways to store electric power at the scale required, so our technology is an alternative that does away with the need to store electrical power.

4. The above-ground power plant footprint is limited to a shack the size of a large house, containing the steam turbine, electric generator, and step-up transformers to dump the power onto the grid.  This means the space required by our power plant is very small, making the power plant unobtrusive and leaving behind very little material which requires eventual recycling, storage, or disposal.

5. We can use this technology to create a long-lived power plant in any of the locations where we can also drill an oil well, which means pretty much anywhere on the planet.  Since there is such a small plant footprint, no plant emissions, no things that might explode and take out buildings a mile or more away, and no danger of a plant melt-down releasing radiation, we can co-locate our power plant where all the people live, so globe-spanning power cables are not required to deal with the fact that it's not always windy or sunny on one specific spot on the Earth.

6. Our power plant can last as long as any traditional coal or nuclear power plant, because it's based upon the exact same boiling water technology to generate electric power, but needs very little infrastructure (no coal trains, coal mines, Uranium mines, reactor cooling water ponds, etc) that those other power plants require.  The only thing we swapped out was the heat source.  No parlor tricks or magic was required.  The interior of the Earth has always been very hot, humans have known this since we've known how to make a fire, and gravity ensures that will remain the case until Earth ceases to exist.  Modern drilling technology allows us to tap into geological heat sources in an economical way.  That's all we did here.  It's a novel use of the Earth and drilling technology to create electrical power or direct thermal power for heating homes or powering industrial processes that require low to moderate temperature heat.

This is the explanation for the engineering that should be present on their website and in their videos:

We need purified water to charge our system, but since our system is a closed loop, after we get this initial charge of water, we never require substantially more water.  Inside our system's giant buried radiator, heat from the Earth causes this water to boil and become steam.  The steam passes through a geared steam turbine, which drives our electric generator, producing electric power.  The water condenses back into liquid water after giving up its heat energy to drive the steam turbine, the water flows back into the giant radiator to be re-heated into steam, and then the cycle repeats.  This method of operation is exactly like the geared steam turbines that powered military ships during WWI and WWII, which were also closed loop systems.  The only difference is that our heat source is provided by the enormous temperatures and pressures found deep within the Earth itself, rather than by burning coal and fuel oil or splitting atoms the way those steam powered ships did.

This concept is not new, nor particularly novel.  It's simple enough to explain to almost any adult in the modern world.  It's a concise explanation of how electric power is being generated, with an explanation of how it compares to similar preexisting technology.  It's also a 100% accurate description of what their technology is actually doing.  Sell people on the idea of simplicity, reliability, longevity, non-toxicity, and reasonably low-cost compared to the alternatives.  Stop trying to sell magic.  Anyone who sells power should be selling engineering and what series of trade-offs are involved, not magic, not futurism, nor any other pseudo-religious fairy tale "green energy" nonsense.

This kind of technology dovetails quite nicely into the concept of using hot water to power short-range vehicles that greatly resemble the giant SUVs that the buying public actually wants, but without burning anything.

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#287 2023-08-01 12:36:08

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Thanks for your expressed concerns.  I do watch Eavor from time to time.  Last time I looked they were having a fluid mix that might include benzine. [THE MENTION OF BENZINE WAS AN ERROR IN THE ORIGINAL POST. Butane IS A MORE LIKELY FLUID USED.]  However, I do believe that they are moving to the west of the USA and that they are learning to drill deeper, so maybe in those cases water may be the fluid to use.  In the west of the USA, geothermal may be more promising and would not requires resort to Hydrocarbon fluids.

But I brought them in using the notion that low grade heat from one of their well systems might be boosted to 800K to provide industrial heat, using a heat pump.  I recently read of the notion that heat pumps are possible to do that.

Calliban pointed out that they would not work well from 300K>800K, but if what comes out of a Eavor well, or it's left over waste heat were used, a heat pump might give ~~~500 C or maybe 800K.

I do understand your dislike of overstatement of capabilities.  However, I have not yet seen the notion of using a heat pump with an Eavor Well to get industrial grade heat, so I felt it would not hurt to speculate for it.

Done.

https://spp.ucalgary.ca/sites/default/f … Hallee.pdf
Quote:

• Eavor-Loop™ is a multi-leg closed-loop advanced geothermal system
capable of producing industrial-scale heat for district heating or
electricity via an Organic Rankine Cycle (ORC) power plant with zero
greenhouse gas (GHG) emissions [1].
• Energy for the University of Calgary main campus is currently supplied by
a 14 MW natural gas turbine producing combined heat and power (CHP)
connected to a district heating system.
• Eavor-Loop™ energy could reduce the carbon intensity of the University
of Calgary’s energy system, integrate into the existing district heating
infrastructure, and support the university’s climate commitment of a
carbon-neutral campus by 2050 [2]

Done

Last edited by Void (2023-08-02 06:48:35)


Done.

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#288 2023-08-01 16:47:17

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,431

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Void,

Now I know why Eavor was so coy about what they're using as a working fluid.  I would have a hard time telling my investors that I wanted to pump millions of gallons of a well known carcinogen into the ground, for some pointless increase in performance.  Hydrazine might be a viable thermal power transfer fluid as well, yet no sane environmental regulator will ever approve this particular use, nor will it pass the smell test applied by rational investors who have technical teams to evaluate the business case for new ideas before they start handing out money.  This idea is a bit like wanting to intentionally manufacture TNT inside the core of a nuclear reactor.  Just because you can, doesn't mean you should.

From the US CDC:

The Department of Health and Human Services (DHHS) has determined that benzene causes cancer in humans. Long-term exposure to high levels of benzene in the air can cause leukemia, cancer of the blood-forming organs.

Enough said.

Whenever someone tells me they're burning wood, making semiconductors, mining Copper / Lithium / Rare Earth metals, or using known carcinogenic chemicals like benzene to create "green energy", I'm forced to stop and ponder over how zealous and irrational the focus on tiny quantities of CO2 in the atmosphere has become.

Simpler and less toxic solutions exist, but nobody seems interested in practical problem solving using what's commonly available.  Everything has to be new and novel, or there's no investment dollars for them.  Decades ago, we focused on solving our problems in more practical ways.  If we knew something didn't work, wouldn't scale, or couldn't function as desired, we moved on to other potential solutions.  Geothermal power has been with us for a very long time, whereas directional drilling is a much more recent technology.

Reinventing the wheel when it comes to thermal power transfer fluids is a waste of time.  We have used water, molten salt, molten metal, CO2, and other refrigerants for many decades, because they're widely available, have known failure modes, and spilling some of it is unlikely to kill a bunch of people.  After we figured out how toxic benzene is, we quit using it for anything outside a lab or chemical processing plant, because it was a mistake.  I feel like nobody at these startups, regardless of how technically brilliant they are, has any clue about the history of technology.

This is probably just crazy talk, but maybe these technology startups require the services of consultants who are technological historians so that nobody there thinks a steam kettle requires any novel aspects of operation to be a good steam kettle.  I bet they have lawyers on speed dial, but nobody to tell them where we've already been, thus where else we could feasibly take energy technology that might be worthwhile.

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#289 2023-08-01 19:35:19

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Very sorry, the fluid seems to be Butane.  I had to check it.  But there may be additives.

I think that the expectation is that they can keep it in the tubes effectively.

Keep in mind that I simply selected Eavor as a potential source of lower temperature heat, which might be boosted up to ~800K to provide industrial heat.  That temperature of about 500 C is supposedly good enough for about 1/2 of industrial processes that need heat.

But my main focus would be the heat pump process, so some other source of lower grade heat may be suitable instead of Eavor.

Done.

Last edited by Void (2023-08-01 19:37:50)


Done.

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#290 2023-08-02 02:02:19

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,434

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Alkanes begin to decompose at temperatures of 400°C.  So you cannot use them as heat transfer fluids above 400°C.  They will coke up the heat transfer surfaces.
https://www.sciencedirect.com/science/a … 7013001009

If you want to pump heat from say 30°C to 500°C, you ideally want a substance with a triple point temperature less than 30°C and a critical point temperature greater than 500°C and will not change chemically as a result of heating.  You want a fluid that will condense at 500°C under pressure, which can be pumped as saturated liquid into a boiler.  I don't think there are any fluids that fit the bill.  You could use an inert gas like argon.  But pumping losses between the condenser and expander will be high, because the fluid will not condense in the condenser.  This will degrade the COP.  Argon has the advantage of at least being chemically stable at high temperatures.  It will not coke heat transfer surfaces or corrode them.  At a temperature of 500°C, low alloy steels lose about 50% of their room temperature strength.  So this is probably the practical limiting temperature for a heat pump.

Last edited by Calliban (2023-08-02 02:14:57)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#291 2023-08-02 06:21:55

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,219

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

For Void re benzine vs butane ....

As a suggestion .... in case someone may read your posts in the future, and this topic in particular....

It appears there might have been an error ? in posting "benzine" instead of "butane"  ... the word "benzine" produced a post that expressed serious concern about use of that material.  You subsequently offered a correction the material might have been butane.

Without changing the original post, it would not be out of order for the creator of the post to add a clarification at the point where the incorrect word was used.

(th)

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#292 2023-08-02 06:50:42

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

(th), I have complied with your request and added mention of the error and correction needed, while not falsifying the original posts error existence.

For Calliban and others, here is the article that got me going again in the last few days for this topic: https://www.bing.com/videos/search?q=El … &FORM=VIRE  Quote:

Elon Musk Just LEAKED A Heat Engine That Will SHOCK Everyone!
YouTube17K views
1 week ago
Elon Musk Evolution
517
Posts
137K
Followers

Here is something about the Cobra Heat Pump: https://www.dlr.de/en/latest/news/2022/ … n-industry  Quote:

Pilot plant in Cottbus reaches temperatures of 300 degrees Celsius – the process heat is sufficient for several industrial sectors.
High-temperature heat pumps are an alternative to fossil fuels.
CoBra works with dry air.
Focus: Energy, digitalisation, technology, heat transition, decarbonisation

I think that the target of 550 C is aspirational, and is seeming to be a top limit of what is possible/practical.  Still 300 C is significant and apparently they use air as the item to draw heat from.

I suspect that an Eavor well or solar storage of some kind might be a substitute, and could provide more heat input, but with an extra cost for the lower stage device itself. 

So, in the case of Eavor geothermal, the working fluid of it would most likely not be used in the heat pump itself.

Then that brings the question of solid heat exchangers between stages.  I presume that 3D printing can make them more economical to produce for such purposes.

So, thanks Calliban for giving warning about the upper limits of Eavor working fluids as ~400 C???  But apparently, they will not use that fluid in the highest temperature heat pumps, if they were to try it.

----------------------

Of course there are desired results and the results that are to be discovered.  It is not yet known what the true limits of practicality and cost will be.

Done.

Last edited by Void (2023-08-02 07:27:25)


Done.

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#293 2023-08-02 10:07:44

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

The title of this topic being " Geothermal and Geo stored Energy", multiple elements could be included.

Solar Photovoltaic, Solar Thermal, Geothermal, Geo Storage, Wind, Tidal, Wave, Nuclear.

Eavor catches my eye as you could do both geothermal and Geo storage with their drilling technology.

Geo Storage might be a rather higher temperature than the geothermal.  For instance, it might originate heat from solar or wind, and serve as a battery for heat.  For this the drilling might not need to be as deep.

Obviously, what you would do in combination would be to service some type of load, and those may not always be the same.

Done.

Last edited by Void (2023-08-02 10:10:33)


Done.

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#294 2023-08-03 11:11:36

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

A good case is made for wind and ground based solar being integrated with geothermal methods.  The two intermittent energy methods being used can be assisted during their down time with geothermal.  During the up time of solar and wind, the Eavor well can accumulate extra heat  into the fluids of the geothermal installation.

For some thinking then this becomes team sports mentality which is actually stone age tribal conflict mentality in my opinion.

If you have several stable energy sources, then you put them in pairs into the Roman Coliseums and have them fight to the death.  Hydro, Geothermal, Nuclear, Space Solar, these can all sort of be considered steady energy sources over long periods of time.

But I consider the binary thinking of the Roman mentality to be the wrong way to go in thinking at this time in this field.

I am guessing that a mentality of co-operative thinking would be more suitable, particularly in this sub compartment of time.

Competition does allow you to stimulate price reductions in some cases for the sources of energy.  But it is also likely to allow one source to kill off the other ones, and then a monopoly allows the "Romans" to gouge the public for the energy.

It has seemed true that more energy is always a better situation, provided you do not cause excessive damage to the world(s) that may be utilized.  Load satisfaction is the complement to the notion of source competition.

I am going to break off for a bit to reset things as my computer is acting very slow.

Thats better for now.

The Roman path can kill the accumulation of skills, as the purpose of the whole system is to appease an emperor, who most likely is quite insulated from understanding the things that the eyes and hands do, and primarily utilizes mouth and ears to project violence to minions to gain control of as much as can be controlled.  This is not particularly useful to us.  We need to accumulate technological skills and abilities; we do not need so much the mouth ear people.  They have their value, but if in excess they will loot the wealth of a society in pursuit of tall dark and handsome men with large penises who can speak treachery and are to be adored by harlot females to be of no account for the benefit of the society.  It is social decay, and we are fighting it off at this time.

Plumbers and Electricians are of much more benefit to society.

As load and the accumulation of eye hand skills are of desires for satisfaction, to favor the multiple sources of energy may satisfy both.

This author may be of interest, I viewed a video of his.  I don't have it, bing is hard to get specific things with for me, but here is something:  https://www.irishtimes.com/culture/book … ars-ahead/

https://peterturchin.com/press/end-time … r-turchin/

I don't intend to suggest that he entertains my notions, but I had a look at his.

Basically too many "Elites" promised too much of a limited pie of money and power for ruling classes, as I interpret it.

Geothermal and some types of geo storage can be in association as in the case of Eavor, drilling "Heat Exchangers" in the rock could facilitate each.

Calliban has been kind enough to post.

Done

Last edited by Void (2023-08-03 12:16:00)


Done.

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#295 2023-08-03 12:10:10

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,434

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

On Mars, huge amounts of low-grade heat will be needed for heating greenhouses and melting ice.  Any source of heat with a temperature greater than the freezing point of water will be useful to us.  This may be the best place to build the first Martian base.
https://en.m.wikipedia.org/wiki/Cerberus_Fossae

Geothermal heat is unlikely to be useful for generating electric power unless we find temperatures high enough to generate high-pressure steam >250°C.  But any heat we can harvest from Mars itself is heat that doesn't have to come from an imported nuclear reactor.  We can optimise those reactors for electric power production if we have low grade heat from other sources.  Ideally, we are looking for warm water brines with a temperature high enough for direct heating (>20°C) or as input to a heat pump (>0°C).  In areas of Mars with recent geological activity, this should be low hanging fruit that we can reach without deep drilling.

Heating and melting ice from Martian ambient temperatures to room temperature, will take about 1MJ of heat for each litre of harvested water.  That would make water expensive on Mars.  If we want abundant water, we need to look for ground water that Mars has already heated to melting point.  This won't be fresh water, but heavily salted brine.  Desalination using ion permeable membranes requires a fraction of energy needed to melt ice.

Solar thermal power will be useful too when ISRU has advanced sufficiently to allow large scale steel production.  Dust storms mean that solar-thermal cannot be entirely relied upon for base life support functions.  But it can contribute to powering industrial activities and waste heat will be useful supporting agriculture.

Last edited by Calliban (2023-08-03 12:21:17)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#296 2023-08-03 12:23:52

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Thanks, Calliban.

I think that that has a good case at this time, as we see some evidence that it can be true.

I myself am very interested in space solar for Mars.  I presume that we are likely to begin developing it for Earth/Moon, so the methods may become established art.  Of course, for Mars we have seasons and dust storms, so we definitely might like the warmth of geothermal and nuclear as well.  I also favor pushing heat into such heat exchangers as a load leveling device.  In that case temperatures suitable to generate electrical power may be possible.  It would be a thermal battery that can push a turbine electric generation process.  Even nuclear reactors may have down times.  But space solar and solar will be intermittent for Mars, similar as for Earth.  Loads may certainly be intermittent.

At this time, my thinking about geothermal for Earth and Mars, is our radioactive materials keep accumulating towards the core of Earth, but for Mars it may be that there are accumulation points higher up, maybe even near the crust?

For Mars, I am inclined to think that Boring Company tubes may be above Eavor type geothermal wells.  So, even in dust storms or winters, indeed you may have quarters to retreat to underground that can be kept warm.  And of course, you would have places for photosynthesis on the surface.  Food is likely easy to be kept in cold and dry conditions on Mars, so intermittency is not a problem for that.

I guess that is enough for now on this coffee session.

Done.

Last edited by Void (2023-08-03 12:37:39)


Done.

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#297 2023-08-04 21:21:52

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

I want to go a bit further with this: AN8LGRS.png

I have not done a picture for a while.  In the above I am supposing an Eavor method, where the black heat exchanger is rock is geothermal, and the red heat exchanger is geostorage.

So, the red would be charged up with heat when convenient, and such a source might be solar of some kind or wind, or even nuclear, or whatever you might have.

Imagine that as desired you may circulate energy sourced from the surface through the red channels and may run the black loop also.  I suppose there would be various methods to switch things out.  In reality the red tube network might run parallel to another black tube network which is not shown but might look like the geothermal one on the bottom.

Charging the red loops could be done with hot water, maybe steam, or just electric currents in a fluid that will conduct reasonably well.

Since you would heat the block loop flow first through the geothermal, and then though the Geo storage, you might reach temperatures suitable to generate electricity, and then a secondary load would be to heat enclosures.

Eavor says that their geothermal is already compatible with wind and solar, but here it might become even more of a battery, both charged by geothermal heat, and also in the red loops by excess intermittent power sources.

Here are some Eavor associated images: https://www.bing.com/images/search?q=ea … 177&ch=488

https://www.bing.com/images/search?view … ajaxserp=0

Where it might make sense to have local heating, maybe industrial heating, I also wonder about batch heating and cooling of homes.

If we were to borrow from our neighbor's concept here: http://newmars.com/forums/viewtopic.php?id=10510, I see a possibility of delivering batches of heat or cold by way of robotics, provided it can be made Full Self Driving also able to hook up to a home system without much human labor.  If you had a local power station, maybe your tesla car could stop into that, and charge up from time to time.

Yes, underground pipes and also power lines make some good sense, but I think batch might work for some situations.

That's enough I guess.

Done.

Last edited by Void (2023-08-05 11:06:45)


Done.

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#298 2023-08-05 10:58:42

Void
Member
Registered: 2011-12-29
Posts: 7,121

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

OK, let's look at this: lKagQp1.png

In my opinion, the Eavor rock drilling technique seems suitable for this.

This would have some characteristics of Electrical and Electronic devices, things I am rather familiar with.

The rock has some of the properties of capacitors or inductors, sort of.  It can store more or less molecular vibrations depending on the input source stimulus and the output load stimulus.

It is a bit like a transformer as you may have 2 or more fluid circuits.

Here I am not focusing on a possible geothermal extraction of heat but working with energy sources from the surface of the Earth more or less.

Another phrase to describe this is a time delayed heat exchanger, with energy storage.

We may or may not involve heat pumps with the Source and/or Load.

We could couple it with this from the previous post: AN8LGRS.png

For the geothermal portion, the Earth's heat from below is the source.

Referring to the Thermal Transformer with Time Delay, we might think to do a lot of strange things.  If you are pulling industrial heat from Air as in the Cobra Heat Pump: https://www.dlr.de/en/latest/news/2022/ … n-industry , you then have a place where you might dump cold.  Not really compatible with heat from geothermal, but a way to store cold for a different use.

On the other hand, if you used the Cobra to cool buildings in Texas for instance in the summer, then you could dump heat into the thermal transformer.  Having multiple loops allows you to use different fluids for heat exchange, and different timings for inputs and outputs, as might be convenient.

I think it is worth considering.

Done.

Last edited by Void (2023-08-05 21:06:35)


Done.

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#299 2023-08-05 14:25:14

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,910

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

I have lots to catch up on for these and many other topics.

Energy-storing concrete could form foundations for solar-powered homes

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#300 2023-08-05 15:07:22

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,431

Re: Geothermal and Geothermal Battery (Changed Title 12/21/23)

Void,

What does the intermittent energy add to the geothermal heat pump design?

Is this some kind of power buffer?

Why not add a separate geothermal power plant and radiator array, or expand / scale-up the existing power plant?

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