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You can have geothermal power everywhere if you drill deep enough

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Re: You can have geothermal power everywhere if you drill deep enough

#211

Post by ravi-delia »

ComradePhil wrote: post #27
anonporridge wrote: post #9

Something I've always wondered. Wouldn't massive scale geothermal end up pumping more heat into the atmosphere that otherwise wouldn't be there? In contrast, the energy collected by solar and wind generators is from the energy added to Earth by the sun and would be energy in our atmosphere regardless of whether or not we collect it. But it seems like the heat inside the Earth's core should be fairly well insulated by…

Solar is also trapping more energy than what would never be there. If the sun's rays just hit the ground, a portion of it would be reflected back. We're using dark material to aborb most of what would be reflected back and we end up trapping more energy than we should... Solar panels are around 15% efficient, which means 85% of this trapped energy is immediately converted to heat, heating the local environment... and…

Except, you know, 100% of the energy obtained by fossil fuels also eventually becomes waste heat. All of our electricity consumption and production is a rounding error to the earth. Global warming only works because the Sun can do most of the work.

Re: You can have geothermal power everywhere if you drill deep enough

#212

Post by 3pt14159 »

oceanplexian wrote: post #167
Joeri wrote: post #80

Earlier quoted context omitted.

Alright, I’ll try to pitch the counter argument. The current green movement narrative is the same it has always been: living within our means. The current fossil fuel driven economy is objectively unsustainable. Yes, you can geo-engineer your way out of the heat problem, but that doesn’t solve all the other problems resulting from unsustainable growth, and who knows what fresh problems this will create. What the gree…

There is no such thing as sustainable growth. Eventually, one day, sooner or later a very unsustainable chunk of high speed space rock will hit the planet and wipe us out, or some other completely natural and “green” disaster, like a supervolcanic eruption, as has happened repeatedly in history. The only thing that will matter is if we advance our technology to a point to divert the problem or make ourselves sufficie…

> The only thing that will matter is if we advance our technology

This is your objective to meet your end which is survival. I don't agree with it, but I'll respond as if I took it for a given.

> As far as I know, the best way for humanity to advance technology is with growth.

What you mean by growth here matters. More people with a higher standard of living is two types of growth. One is economic the other is population. But there are other dimensions to grow across.

For example, peacefulness has produced just outstanding yields in many valuable areas such as productivity, research, and ecological protection. But peacefulness did not arise out of nothing. It took lives to create our world which is peaceful for most people. Real people working on arms control agreements and diplomacy.

Improving education is similar. You could argue that education requires resources, and that is true to a point, but we are well, well past that point. North Korea is capable of nuclear weapons and rocketry. Most elementary school programs can get by on $100 worth of reusable books a year and some paper and pens.

Now the green model has some fatal flaws, and there is a reason I'm a Canadian Liberal not a Green, but the core thrust of Green thinking is a good thing in my opinion because I've found that, in general, prevention is more efficient than cure because it's easier to align incentives with prevention.

One of the problems with incentive alignment is that the international system is anarchistic and individual choices are unpredictable and given over to passions that are often unethical. This leads to unavoidable arms races (literal and figurative) across multiple aspects of society and politics.

So, for example, China builds new coal power plants because they're in a power competition with the West and to build wind turbines instead would cost a non-trivial portion of their GDP and institutional focus.

Anyway, in summary, yes with what you outlined as your objective economic growth matters, but so do other forms of growth. I would even include spiritual growth (or decline) matter too. People are acting incredibly sanctimonious and paranoid right now and it isn't helping their more charitable instincts.

Re: You can have geothermal power everywhere if you drill deep enough

#214

Post by unfocussed_mike »

raducu wrote: post #166
kragen wrote: post #97

Earlier quoted context omitted.

Conventional “mechanical” drilling isn’t very heat tolerant because heat softens metal. For oil and even gas drilling it doesn’t need to be; they’re located in cooler rock. For supercritical steam EGS heat tolerance is a sine qua non. Conventional approaches might still work best, but it’s also plausible that what’s best for gas isn’t best for EGS.

But if we get to temperatures that destory metals, isn't it enough? Why don't we drill to whatever is the termal limit, make a big cavity there, install radiators there and just heat the watter to that temperature and take it out to surface where we can heat homes. I know this is done in Bucharest for a water park (to much lesser depths because apparently we have hot springs near Bucharest). Do we need to reach magma…

> Do we need to reach magma?

Nooo --- don't dig the Well to Hell!

https://en.wikipedia.org/wiki/Well_to_Hell_hoax

Re: You can have geothermal power everywhere if you drill deep enough

#215

Post by yissp »

hedora wrote: post #200
sidewndr46 wrote: post #175

Earlier quoted context omitted.

I've heard of launching some large mirrors into orbit, or a bunch of small mirrors that can link together in orbit. Then you use them to reflect some sunlight off into space. I have no idea how practical this is. The bigger concern would be if something goes wrong, you need to make the mirrors deorbit quickly.

You could set it so that some of the mirrors formed a parabolic collector and heated a molten salt column, etc on the surface. That'd have the same net effect as the giant heat sink (energy production from a heat engine, net negative flow of energy to the surface). Wasn't there a city builder that'd let you build such a thing, where it would sometimes lose calibration and burn a swath of the city to the ground?

Futurama had a similar joke (with a reflecting mirror, not a heat collector) https://gfycat.com/hatefulvariablekakapo

Re: You can have geothermal power everywhere if you drill deep enough

#216

Post by charles_f »

Somewhat related, I used to think that residential geothermal heating was basically harvesting the steaming heat from the soil to your house. I figured that would require seating on a volcano.

In fact it's using a heat pump, and liquid circulating in pipes burried a few feet underground to act as a thermal sink, to either heat or cool down a house. This works well because the temperature in the ground doesn't fluctuate much past 3ft. Pretty neat, and does not require to go down miles (though it's moving energy to/from ground rather than harvesting it and you still need an energy source for the pump)

Re: You can have geothermal power everywhere if you drill deep enough

#218

Post by philipswood »

anonporridge wrote: post #23
tinco wrote: post #20

Earlier quoted context omitted.

You are correct in that the earth core is really well insulated from the surface. So well that the light of the sun delivers an order of magnitude more energy per M2 to the Earth's surface. That information also answers your question, our problem isn't with the amount heat we produce, it's with how much of that solar radiation we trap in our atmosphere due to the green house effect of CO2 and similar gases. So yeah w…

I've had the thought for a while now that it might be a good idea to start changing the climate change narrative to a problem of planetary heat engineering, not simply a problem of GHG reduction. The current narrative is largely defeatist and regressive. It's largely about rolling back growth and the amount of energy civilization has harnessed. But if the narrative was altered to be a heat engineering problem, then i…

I personally like the idea of a satellite swarm that can tweak (in a controlled manner) 2% of incoming solar radiation.

An artificial ring system for earth made out of reflective satellites.

Re: You can have geothermal power everywhere if you drill deep enough

#219

Post by aaronblohowiak »

kragen wrote: post #192
raducu wrote: post #166

Earlier quoted context omitted.

But if we get to temperatures that destory metals, isn't it enough? Why don't we drill to whatever is the termal limit, make a big cavity there, install radiators there and just heat the watter to that temperature and take it out to surface where we can heat homes. I know this is done in Bucharest for a water park (to much lesser depths because apparently we have hot springs near Bucharest). Do we need to reach magma…

This is about running your air conditioner, charging your Tesla, and molding your kitchen sink, not heating homes. Think Carnot efficiency, power density, supercritical steam, and shutting down gas pipelines. And the temperature to destroy steel under the immense mechanical stress of a drill string is surprisingly modest. Jet fuel can’t melt steel beams, but softening them is enough.

In a fire, A wooden ladder remains viable king after an aluminum one! Soft happens WAY before melt

Re: You can have geothermal power everywhere if you drill deep enough

#220

Post by RugnirViking »

pharke wrote: post #162

If we converted all energy production to geothermal, would it be possible to significantly increase the cooling of the Earth's core? The flow from the Earth's core to the surface is estimated at 47±2 terawatts[0] The total energy supply for 2017 was 162,494 TWh[1] World energy demand is expected to grow 27% by 2040 Currently, heat escaping from the Earth accounts for only 0.03% of Earth's total energy budget at the s…

surely there must be some numbers wrong here? How can the total energy supply be only just barely less than the entire amount of energy applied to the planet by solar radiation?

Is it suggesting that covering the entire surface of earth with 100% efficient solar panels would just barely cover 2017's power supply?

Edit: ah I see, world energy is in terawatt hours for an entire year, wheras planetary solar energy is terawatts in a single hour

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