As NASA moves forward with the plan to travel to mars, I believe there are many things that we can learn from them, and maybe even use in a long term bomb shelter.

After reading a Popular Mechanics article where they did a 2 week test with a guy getting all his air supply from....Wheat. If we could sustain power long enough for grow LED's, and had a clean source of water (such as well), and seeds, we could sustain life underground for months or even years. If we could use electric heaters to turn water to steam, we could build
an underground steam engine to produce power, and power lights that'll grow food.

An expense is a major factor in this, but even if you didn't ever use it, it would be a great learning experience.

Your thoughts?

It's an interesting idea but I think part of the point is rendered moot since most retreats are in places not targeted by nukes or hypothetical bio-weapons and that those who are under the "fallout cloud" blanket can do with filtration rather than generation/recycling.

The problem is that you can't keep 100% of the energy in any cycle (especially with steam engines), you would still need an exterior source of renewable energy like wood, solar or otherwise and if the outside is nuked or too dangerous, you'd better hope your diesel or gas storage tank doesn't run dry...

MY POV on this is that it's an interesting option but I'd still rather not live in an attack zone or downwind of one...

more Morlock (sp?) than Eloi, huh?

Quoted: snip.. If we could use electric heaters to turn water to steam, we could build an underground steam engine to produce power, and power lights that'll grow food. ...snip... Your thoughts?

if we use electricity to power a steam genterator to run lights why not just use the electricity to run the lights.

Quoted: Quoted: snip.. If we could use electric heaters to turn water to steam, we could build an underground steam engine to produce power, and power lights that'll grow food. ...snip... Your thoughts? if we use electricity to power a steam genterator to run lights why not just use the electricity to run the lights.

I think he has it backwards, steam can power a generator for electricity.

Electric power to heat steam is a lot like having an electric powered windmill so as to blow air at your other windmill.

Quoted: Quoted: Quoted: snip.. If we could use electric heaters to turn water to steam, we could build an underground steam engine to produce power, and power lights that'll grow food. ...snip... Your thoughts? if we use electricity to power a steam genterator to run lights why not just use the electricity to run the lights. I think he has it backwards, steam can power a generator for electricity. Electric power to heat steam is a lot like having an electric powered windmill.

yes, but he specifically mentioned electric heaters, and if it is as you say where would the energy come from to turn the water to steam?

Quoted: As NASA moves forward with the plan to travel to mars, I believe there are many things that we can learn from them, and maybe even use in a long term bomb shelter. After reading a Popular Mechanics article where they did a 2 week test with a guy getting all his air supply from....Wheat. If we could sustain power long enough for grow LED's, and had a clean source of water (such as well), and seeds, we could sustain life underground for months or even years. If we could use electric heaters to turn water to steam, we could build an underground steam engine to produce power, and power lights that'll grow food. An expense is a major factor in this, but even if you didn't ever use it, it would be a great learning experience. Your thoughts?

You mention going to Mars....

Long duration Space craft depend largely on solar power, this may be difficult in a cave.

Future long duration space craft may depend on nuclear generators.

Comparing a Mars Base sort of operation/habitat to an underground habitation.

On Mars they will utilize solar power, and possibly nuclear.

Mars has water, which will also provide oxygen, later on crops would also provide oxygen

How much wheat is required to provide oxygen for each person?

Underground, you need power first, then everything else becomes possible.

It would need to be a source of continuous power, solar, wind, hydro or nuclear.

Steam requires either burning of fuel or a nuclear reactor.

   

Quoted: Quoted: Quoted: Quoted: snip.. If we could use electric heaters to turn water to steam, we could build an underground steam engine to produce power, and power lights that'll grow food. ...snip... Your thoughts? if we use electricity to power a steam genterator to run lights why not just use the electricity to run the lights. I think he has it backwards, steam can power a generator for electricity. Electric power to heat steam is a lot like having an electric powered windmill. yes, but he specifically mentioned electric heaters, and if it is as you say where would the energy come from to turn the water to steam?

Where it it has always come from, burning fuel, be it wood or coal, unless you have fuel to burn you can forget about steam. Even if you had some source of electricity to heat a boiler, it would be at a considerable net loss, you wont get out what you put in, there is no point to it.

If you have fuel and are able to run a boiler it is possible to use the steam to create electricity as well as run various machines, and of course provide heat. This makes sense in many situations.

So you need fuel and you also need a chimney. Without these forget steam.

So far as I know the only efficient "closed system" steam power plants are on board nuclear submarines.

If one could build such an installation underground, it could supply power and heat on a very long term basis.  




 

It's theoretically possible to build an underground installation (much larger than a 'bunker') that could support a small population (a family or two) for a year. But it would need some expert engineering and plumbing.

First of all, an underground source of water and an underground reservoir that funnels through a pipe with sufficient 'drop' to turn a turbine = electricity.

Geothermal pipes could also produce steam for heating/cooking (boiling water).

You'd need a faily large space for 'air entrapment' and another few spaces for plants, fish tanks, dry food storage, air locks and even a small stable for chicken, rabbits, turtles, and hoof stock. with their feed and hay etc.

All told we're talking 'an ark' or submarine size cave/series of tunnels.

It's definately do-able, but not in most of our income levels. It would cost AT LEAST $10 m to excavate, stock, etc.

A nucleur reactor could make it possible for a whole lot of people to live underground for a very long time. Now if one doesn't have access to that kind of technology what kind of alternatives are there. Mmmmm, there is a few. Easiest would be a  undergound stream. They do exist and if you could find one with a good flow you could just have your own underground hydroelectric plant.
Other idea:
Lets say one used a very large cave system or abandoned mine. Once one starts getting a good distance underground it starts getting warmer. Which is why much electricity gets spend cooling the things. Instead one could just use the temperature differencial between the upper and lower parts of the mine/cave to generate electricity. Solid state technology produces so little electricity its in the category of why bother. Instead I think just seal off the upper and lower parts into two halves. Have something like a steam engine right where the two halfs meet, but running on something that turns to gas at a lower temperature the water would. Then use the electricity to cool and make liveable some small section of the place.

 If the area is volcanic, drill a hole down and do geothermal power.

Very few undergound workings of any depth are dry, so pumping may be an issue.  The geothermal gradient does exist but is highly dependant upon the area.  In central CO a 2000 foot deep mine will be a constant 65 F.  In northern Idaho, 2000 feet down equals mid to high 80's.

Underground work is expensive.  Using a contractor, figure $200-$250 per foot of advance for a 10'X10' drift.  Shafts are even more.

You'll have to consider ground support.  Most excavations are not self supporting.  You'll also need one or more emergency escapeways.  Ventilation is always an issue and you don't want to contaminate your air with products of incomplete combustion.

Power is the key.  One of the most important developments is the small self-contained nuclear powerplants.

Of course, I could be wrong.

SRM

Quoted: So far as I know the only efficient "closed system" steam power plants are on board nuclear submarines.

Submarine plants are not closed systems. They use seawater for cooling. And in a true underground setup, waste heat is going to be an issue. Not to mention humidity control.

What's interesting about space operations is that waste heat must be rejected by thermal radiation, as there's no air or water to remove the waste heat by convection, and at least for orbital objects and spacecraft there's nothing touching them, so no conductive heat rejection either. One method that is used is the heat pipe, which is a neat little thing that has its own little fluid-based cycle for absorbing waste heat from the spacecraft, moving it outside the spacecraft, and radiating the heat away into space. Not terribly practical for we low-budget folks, however.

Quoted: Quoted: So far as I know the only efficient "closed system" steam power plants are on board nuclear submarines. Submarine plants are not closed systems. They use seawater for cooling. And in a true underground setup, waste heat is going to be an issue. Not to mention humidity control. What's interesting about space operations is that waste heat must be rejected by thermal radiation, as there's no air or water to remove the waste heat by convection, and at least for orbital objects and spacecraft there's nothing touching them, so no conductive heat rejection either. One method that is used is the heat pipe, which is a neat little thing that has its own little fluid-based cycle for absorbing waste heat from the spacecraft, moving it outside the spacecraft, and radiating the heat away into space. Not terribly practical for we low-budget folks, however.

I was mostly referring to the means of heating the steam, recirculating most of that steam. As far as reactor cooling goes, I'm assuming there is flowing water available in this cave, lots of it because you don't build a reactor to generate steam without a ready supply of water. Controlling waste heat and humidity would all be design prioritys and would be dealt with by smarter people than I.

All this would cost many millions of dollars and I think if you have sufficient money anything is possible.

Would this help?

link

Quoted: more Morlock (sp?) than Eloi, huh?

Jesus that was phunnie.......and not one laugh? Are you guys really alive?

Quoted: Would this help? link

I'll take four!

Quoted: Quoted: more Morlock (sp?) than Eloi, huh? Jesus that was phunnie.......and not one laugh? Are you guys really alive?

I'm already well down the Morlock road....my sense of humor went ahead of me.

Quoted: Quoted: Would this help? link img.photobucket.com/albums/v668/scott1959/Smith1.jpg I'll take four!

Maybe we can get a group buy..

Drill deep enough and it will get hot enough to produce steam with out burning anything. Look into how deep the old mines were and how hot it got that far underground.
So, drill a shaft deep enough, a bit of plumbing, vent steam back up into a turbine and then into the air. Of course some sort of water supply will be necessary so a nearby river, lake, spring or just a friendly water table is needed.