question for someone who knows more about Nuke power than me.

[Charles_Main]

As the Problems in Japan have shown. One of the dangers of Nuclear power is the need for power to keep them cool. Lose that power and uh oh.

So I had an idea, would this work?

Most plants are built near large bodies of water or the ocean. What if you dug down and so that the cores were well below the lake or Sea level they are next to, then built a damn. In the event of a serious problem the dam is opened and the plant flooded with water which will continue to be replaced by the lake or ocean with out the need for pump.

Practical?

 

[konradv]

As the Problems in Japan have shown. One of the dangers of Nuclear power is the need for power to keep them cool. Lose that power and uh oh.

So I had an idea, would this work?

Most plants are built near large bodies of water or the ocean. What if you dug down and so that the cores were well below the lake or Sea level they are next to, then built a damn. In the event of a serious problem the dam is opened and the plant flooded with water which will continue to be replaced by the lake or ocean with out the need for pump.

Practical?

The main problem would be containment. You'd have to ensure that radioactivity couldn't contaninate an open body of water. In a meltdown scenario, that might be exactly what you'd be doing.

 

[martybegan]

As the Problems in Japan have shown. One of the dangers of Nuclear power is the need for power to keep them cool. Lose that power and uh oh.

So I had an idea, would this work?

Most plants are built near large bodies of water or the ocean. What if you dug down and so that the cores were well below the lake or Sea level they are next to, then built a damn. In the event of a serious problem the dam is opened and the plant flooded with water which will continue to be replaced by the lake or ocean with out the need for pump.

Practical?

The main problem would be containment. You'd have to ensure that radioactivity couldn't contaninate an open body of water. In a meltdown scenario, that might be exactly what you'd be doing.

Some plants use a modification of this, with a large tank directly over the vessel. The water is often laced with boron, which is a neutron absorber.

The problem with all quench strategies is that the water that leaves the vessel after cooling it, as either hot water or steam, is radioactive. This is not a huge concern as the isotopes created are often very short lived, redndering the fluid safe quickly, but it still cannot be immediately released for fear of contamination. So basically you need a way to store the liquid used for a time before release. This is hard if the water turns to steam while cooling.

This is usually why you try to use a closed loop in the primary containment, as you keep the radiation inside.

 

[Midnight Marauder]

You are going to need pumps anyway. For the turbine water. I'll explain.

People don't understand the purpose of the nuclear pile. It is simply to generate massive amounts of heat, to turn water into superheated steam used to turn turbine generators. It is essentially a super boiler, it doesn't magically make electricity out of radiation. Problem is, once the reaction begins you cannot readily stop the heating until the fuel rods expire. Not like let's say, a gas or coal fired boiler, which you can just shut off.

People keep saying the pumping of sea water into the core in Japan is a "hail mary pass" when most likely it is simply because due to the earthquake, the utility is no longer able to supply the plant enough water to do the job. One thing the sea water assures: plants who have to use it will never be operational again.

By the way, had the Japan nuclear power plants had their backup generators installed 20 feet above ground level, the tsunami wouldn't have gotten to them and affected them, and they would never have had a problem at the plant. This is IF the utility water supply wasn't also affected. It was just a confluence of issues causing their problems there. No one foresaw such a huge tsunami.

 

[Two Thumbs]

As the Problems in Japan have shown. One of the dangers of Nuclear power is the need for power to keep them cool. Lose that power and uh oh.

So I had an idea, would this work?

Most plants are built near large bodies of water or the ocean. What if you dug down and so that the cores were well below the lake or Sea level they are next to, then built a damn. In the event of a serious problem the dam is opened and the plant flooded with water which will continue to be replaced by the lake or ocean with out the need for pump.

Practical?

The basics of that is fairly sound.

the idea that radiation will poison the water is nominal compared to letting it blow and dealing with it airborn. The reason is that if you submerge the plant, which is what I think you are going with, would cause a lot of rapid cooling with little steam, since it's submerged, the hot water would cool.


the plants on Nuke subs was designed to melt through the hull if it got to hot.

 

[Midnight Marauder]

Also, if the pressure got too great (wouldn't take much), water would not just flow in by gravity. You would still need to pump it in.

Toshiba however, DOES have nuclear reactors about the size of a school bus, that are designed to be buried in the ground 90-some feet deep. The Toshiba 4S. also called the "Nuclear Battery." Right now they have a 10MW version, with a 50MW version to come later. Meltdowns and the like aren't a problem, 90 feet underground.

These are the answer to future nuclear power IMO. They don't rely on water for cooling of the pile.

 

[martybegan]

Also, if the pressure got too great (wouldn't take much), water would not just flow in by gravity. You would still need to pump it in.

Toshiba however, DOES have nuclear reactors about the size of a school bus, that are designed to be buried in the ground 90-some feet deep. The Toshiba 4S. also called the "Nuclear Battery." Right now they have a 10MW version, with a 50MW version to come later. Meltdowns and the like aren't a problem, 90 feet underground.

These are the answer to future nuclear power IMO. They don't rely on water for cooling of the pile.

I assume that the plants would use a modular approach, so the units can be so small that in the event of a SCRAM the residual heat could be removed using natural convection, or even use the earth as a heat sink in case of a catastrophic shutdown.

 

[Midnight Marauder]

Also, if the pressure got too great (wouldn't take much), water would not just flow in by gravity. You would still need to pump it in.

Toshiba however, DOES have nuclear reactors about the size of a school bus, that are designed to be buried in the ground 90-some feet deep. The Toshiba 4S. also called the "Nuclear Battery." Right now they have a 10MW version, with a 50MW version to come later. Meltdowns and the like aren't a problem, 90 feet underground.

These are the answer to future nuclear power IMO. They don't rely on water for cooling of the pile.

I assume that the plants would use a modular approach, so the units can be so small that in the event of a SCRAM the residual heat could be removed using natural convection, or even use the earth as a heat sink in case of a catastrophic shutdown.

I think that's the idea. That and underground containment of any radiation.

The steam turbines with their attached generators are located above ground in a small building, their super-heated steam and condensate return is also a closed system, using heat exchangers to capture the heat from the pile and transferring this heat to the water inside the heat exchangers. This system is standard also, for conventional nuclear power plants. We're just making lots of super-heated steam people, to turn generators to produce power.

By the way, when the fuel is expired after 50 years or so, we simply leave them buried and sealed, and install another one on the property and hook it up! Waste storage taken care of!

 

[dilloduck]

Where is Homer Simpson when we need him ?

 

[Skull Pilot]

Mini nuclear plants to power 20,000 homes | Environment | The Observer

Nuclear power plants smaller than a garden shed and able to power 20,000 homes will be on sale within five years, say scientists at Los Alamos, the US government laboratory which developed the first atomic bomb.

The miniature reactors will be factory-sealed, contain no weapons-grade material, have no moving parts and will be nearly impossible to steal because they will be encased in concrete and buried underground.

The US government has licensed the technology to Hyperion, a New Mexico-based company which said last week that it has taken its first firm orders and plans to start mass production within five years. 'Our goal is to generate electricity for 10 cents a kilowatt hour anywhere in the world,' said John Deal, chief executive of Hyperion. 'They will cost approximately $25m [£16m] each. For a community with 10,000 households, that is a very affordable $2,500 per home.'

Deal claims to have more than 100 firm orders, largely from the oil and electricity industries, but says the company is also targeting developing countries and isolated communities. 'It's leapfrog technology,' he said.

The company plans to set up three factories to produce 4,000 plants between 2013 and 2023. 'We already have a pipeline for 100 reactors, and we are taking our time to tool up to mass-produce this reactor.'

The first confirmed order came from TES, a Czech infrastructure company specialising in water plants and power plants. 'They ordered six units and optioned a further 12. We are very sure of their capability to purchase,' said Deal. The first one, he said, would be installed in Romania. 'We now have a six-year waiting list. We are in talks with developers in the Cayman Islands, Panama and the Bahamas.'

The reactors, only a few metres in diameter, will be delivered on the back of a lorry to be buried underground. They must be refuelled every 7 to 10 years. Because the reactor is based on a 50-year-old design that has proved safe for students to use, few countries are expected to object to plants on their territory. An application to build the plants will be submitted to the Nuclear Regulatory Commission next year.

'You could never have a Chernobyl-type event - there are no moving parts,' said Deal. 'You would need nation-state resources in order to enrich our uranium. Temperature-wise it's too hot to handle. It would be like stealing a barbecue with your bare hands.'

Other companies are known to be designing micro-reactors. Toshiba has been testing 200KW reactors measuring roughly six metres by two metres. Designed to fuel smaller numbers of homes for longer, they could power a single building for up to 40 years.

 

[Skull Pilot]

The Big Idea - Small Town Nukes - National Geographic Magazine

They'd be carbon free, relatively cheap, and according to the industry, inherently safe. An underground mini-nuke could power a village.

Most nuclear power plants are behemoths, big enough to power a medium-size city. They are also behemoth investments, costing upwards of several billion dollars each to construct. Small wonder then that dozens of small-reactor prototypes are vying for attention in an industry newly energized by nuclear power's advantages as a low-emission alternative to fossil fuels.

"Small reactors can't address all the problems standing in the way of more nuclear investment, but they can address the biggest barriers—the economic ones," says Richard Lester, head of nuclear science and engineering at MIT. Building giant reactors, he points out, isn't the only way to achieve economies of scale; another way is to mass produce inexpensive mini-nukes. If they're designed as modules, a single unit might power a remote town or mine, while a dozen used in tandem could match the output of a traditional nuclear plant. In the developing world, small reactors would place less strain on fragile electrical grids. And the ability to start small and gradually add power modules could appeal to cash-strapped utilities everywhere.
None of the new small reactors have been deployed yet. Some, like the one designed by NuScale Power, are light-water reactors that resemble ones long used on warships. Others are more novel. Toshiba and the Japanese Central Research Institute of Electric Power Industry are working on a liquid-sodium-cooled "nuclear battery." Delivered partially assembled and installed underground, the reactor would generate ten megawatts for 30 years until it needed refueling. The isolated Alaska village of Galena is in discussions with Toshiba to become its first customer.

Besides costing less to build, some small reactors could be inherently safer, says Vladimir Kuznetsov of the International Atomic Energy Agency. NuScale's design requires no reactor cooling pumps, while Toshiba's pumps are electromagnetic, without moving parts; either approach diminishes the possibility of a disastrous failure. Chinese researchers, meanwhile, are developing a small reactor in which the nuclear reaction itself is self-limiting. In a dramatic 2004 demonstration, they turned off the cooling system; the reaction just burned itself out. With any of the new reactors, of course, there will still be radioactive waste to contend with.

There are 56 reactors under construction in the world today, 19 in China alone. But with energy demand soaring—and the threat of climate change looming—even that much construction will not greatly increase nuclear's share of the global electricity supply. Small reactors could help, Lester says. "The point is to scale up low-carbon energy sources rapidly. Nuclear has great potential to do this." If regulators go along, that is. In the U.S., officials say some designs may win certification within five years. More innovative ones may take longer.

 

[Charles_Main]

You are going to need pumps anyway. For the turbine water. I'll explain.

People don't understand the purpose of the nuclear pile. It is simply to generate massive amounts of heat, to turn water into superheated steam used to turn turbine generators. It is essentially a super boiler, it doesn't magically make electricity out of radiation. Problem is, once the reaction begins you cannot readily stop the heating until the fuel rods expire. Not like let's say, a gas or coal fired boiler, which you can just shut off.

People keep saying the pumping of sea water into the core in Japan is a "hail mary pass" when most likely it is simply because due to the earthquake, the utility is no longer able to supply the plant enough water to do the job. One thing the sea water assures: plants who have to use it will never be operational again.

By the way, had the Japan nuclear power plants had their backup generators installed 20 feet above ground level, the tsunami wouldn't have gotten to them and affected them, and they would never have had a problem at the plant. This is IF the utility water supply wasn't also affected. It was just a confluence of issues causing their problems there. No one foresaw such a huge tsunami.

No I understand the need for pumps and turbines. My senerio is one in which the plant in question has a serious problem, and is never going to be operational again anyways. The point was to try and come up with a way to keep the core, and spent rods covered in water. In the event that people are not around any longer to keep up with it.

For example, say there is some horrible epidemic and a end days like senerio where 90% of the people on earth die. The way we currently are set up. Even if as society was falling apart. We scrammed all the reactors. As soon as the power goes out you still would have exposed Fuel Rods, and some melting down Reactors for the 10% of live to deal with. I was simply trying to think of a simple Solution that could be used to at least make sure the shit is not sitting completely exposed to the air to fuck everything up for the ones who make it.

 

[Midnight Marauder]

You are going to need pumps anyway. For the turbine water. I'll explain.

People don't understand the purpose of the nuclear pile. It is simply to generate massive amounts of heat, to turn water into superheated steam used to turn turbine generators. It is essentially a super boiler, it doesn't magically make electricity out of radiation. Problem is, once the reaction begins you cannot readily stop the heating until the fuel rods expire. Not like let's say, a gas or coal fired boiler, which you can just shut off.

People keep saying the pumping of sea water into the core in Japan is a "hail mary pass" when most likely it is simply because due to the earthquake, the utility is no longer able to supply the plant enough water to do the job. One thing the sea water assures: plants who have to use it will never be operational again.

By the way, had the Japan nuclear power plants had their backup generators installed 20 feet above ground level, the tsunami wouldn't have gotten to them and affected them, and they would never have had a problem at the plant. This is IF the utility water supply wasn't also affected. It was just a confluence of issues causing their problems there. No one foresaw such a huge tsunami.

No I understand the need for pumps and turbines. My senerio is one in which the plant in question has a serious problem, and is never going to be operational again anyways. The point was to try and come up with a way to keep the core, and spent rods covered in water. In the event that people are not around any longer to keep up with it.

For example, say there is some horrible epidemic and a end days like senerio where 90% of the people on earth die. The way we currently are set up. Even if as society was falling apart. We scrammed all the reactors. As soon as the power goes out you still would have exposed Fuel Rods, and some melting down Reactors for the 10% of live to deal with. I was simply trying to think of a simple Solution that could be used to at least make sure the shit is not sitting completely exposed to the air to fuck everything up for the ones who make it.

Gravity fed water won't work. If it would, that's what the designs would incorporate already.