Zero-emission Power Plants Proposed

ckbreckenridge writes "Supercompact, superfast, superpowerful turbines called ZEPPS (zero-emission power plants), designed to combat global warming, could help produce the electrical power needed to keep up with 21st century demand. They would consume methane and oxygen and produce liquid carbon dioxide, which could be sequestered underground. The current electricity grid would need to be replaced by a 'supergrid' across the USA, says Jesse H. Ausubel in The Industrial Physicist. Work on such a system should start as soon as possible, since CO2 levels leaped up 2 ppm in the past two years as global warming becomes more of a reality."

Comments

Carbon sequestration

[GangstaLean]

IGCC (integrated gas combined cycle) coal plants basically can be retrofitted to do this, at a lower cost than CH3, but the stable long-term options for carbon sequestration seem to be:

1. CaO +CO2 -> CaCO3, conversion to limestone using lime. Problem, most people get lime from baking limestone.
   
2. Capped oil well or deep aquifer storage in gaseous form.
   
3. liquid "bubbles" that are thermodynamically unstable, sink them to the bottom of the ocean or other.
   

The problem with all of these is you have to worry about the re-emergence of the CO2. Limestone seems like a good option because you just have to keep it dry. The downside is that limestone is heavy and even though the production is exothermic, producing lime has not been worked out. Pressurizing CO2 and storing it underground works, unless it leaks out. Then you have the same problem. Liquid bubbles are good if you have a very high pressure place to store them (the ocean), but the long term effect is acidification of the ocean and exhaustion of the carrying capacity (estimated to be around 1000-1500Gtons, we produce around 3Gtons/year).

There aren't any easy answers. However long term, since coal is about 57% of current electricity in the U.S., it's not going away. What carbon sequestration will do is allow us to bridge the gap economically and technologically between high and low carbon fuel sources.

I'm a big fan of wind, but there are still lots of hurdles.

Zero Emission Power Plants Using Solid Oxide Fuel

[Mstrgeek]

This is a well written PDF that was very educational dealing with Zero Emission Power Plants Using Solid Oxide Fuel Cells and Oxygen Transport Membranes

http://www.netl.doe.gov/publications/proceedings /01/vision21/v211-5.PDF

Re:.... Duh?

[TAGmclaren]

I know this isn't a popular option, but there is only one way left to combat CO2 emissions without winding the planet back to the stone age.

It's nuclear power. There is no other technology available that has sufficient output, whilst not outputting CO2 that will put the Florida Quays any further underwater.

The common argument in return is saving CO2 isn't much use if you make the planet uninhabitable due to reactors melting down. Well, the Chinese, with some help from the Germans, have very kindly solved this problem for us. Go check the link out - it's to wired.com - they have developed a nuclear reactor that doesn't go critical when the coolant system is switched off.

We can save the planet, if we're willing to get over the Cold War era stereotypes.

Glad you asked...

[ackthpt]

How is this diffrent then toxic waste from nuclear plants being stored under ground.... if we continue storring all this wouldn't eventually run out of place to put it?

A friend who worked in the Hazardous Waste disposal industry lamented the ignorance of many protesters who came out to his site and harrassed the workers. They didn't know the difference between Hazardous and Toxic waste. CO2 is not toxic. In high concentrations it can be harmful (depending on the lifeform), but that is the definition of Hazardous. Toxic means it does harm even in small concentrations.

Example:

1,000 gallons of horse urine if dumped on a field would probably kill the grass, but if dilluted and spread over time it would not.

1 milligram of plutonium spread on a field would kill the grass, no matter how you dilluted it and grass wouldn't grow again for a long time.

I'm sure I didn't explain this as well as he could have, but I hope you get the gist of it.

Re:Glad you asked...

[multiplexo]

The radioactivity is not the point. Plutonium is exeptional toxic (ie. poison).

BZZZZZZZT! Nuclear bullshit warning! Nuclear bullshit warning! Nuclear bullshit warning! The previous post may have contained bullshit that could be hazardous to your health!

Sorry, to bum your high, but while plutonium is a bad thing it is by no means as toxic as everyone seems to think it is. If you read the encyclopedia entry on plutonium you find that the toxicity has been much exaggerated. The section on oral toxicity in the excerpt below is especially informative.

All isotopes and compounds of plutonium are toxic and radioactive. While plutonium is sometimes described in media reports as "the most toxic substance known to man", there is general agreement among experts in the field that this is incorrect. As of 2003, there has yet to be a single human death officially attributed to plutonium exposure. Naturally-occurring radium is about 200 times more radiotoxic than plutonium, and some organic toxins like botulism toxin are still more toxic. Botulism toxin, in particular, has a lethal dose in the hundreds of pg per kg, far less than the quantity of plutonium that poses a significant cancer risk. In addition, beta and gamma emitters (including the C-14 and K-40 in nearly all food) can cause cancer on casual contact, which alpha emitters cannot.

Orally, plutonium is less toxic than several common substances, including caffeine, acetominopnen, some vitamins, (pseudo)ephedrine, all narcotic pain killers (including codeine) and any number of plants and fungi. It is perhaps somewhat more toxic than absolute alcohol, but less so than tobacco and most illegal drugs (some such as LSD and marijuana are not or barely toxic). As such, it is debatable whether plutonium should even be classified as a poison. (emphasis mine)

That said, there is no doubt that plutonium may be extremely dangerous when handled incorrectly. The alpha radiation it emits does not penetrate the skin, but can irradiate internal organs when plutonium is inhaled or ingested; particularly at risk are the skeleton, which it is liable to be absorbed onto the surface of, and the liver, where it will collect and become concentrated. Extremely small particles of plutonium on the order of micrograms have a (small) chance to cause lung cancer if inhaled into the lungs.

Other substances including ricin, botulinum toxin and tetanus toxin are fatal in doses of (sometimes far) under one milligram, and others (the nerve agents, nutmeg by injection, the amanita toxin, the fugu toxin) are in the range of a few milligrams. As such, plutonium is not unusual in terms of toxicity, even by inhalation. In addition, those substances are fatal in hours to days, whereas plutonium (and other cancer-causing radioactives) give an increased chance of illness decades in the future. Considerably larger amounts may cause acute radiation poisoning and death if ingested or inhaled; however, so far, no human is known to have died because of inhaling or ingesting plutonium and many people have measurable amounts of plutonium in their bodies.

The chemical and radiological toxicity of plutonium should be distinguished from eachother and further, from the potential danger of a runaway fission reaction or "criticality". Many, both in the anti-nuclear movement and in the continuing green politics movement, refer to plutonium as the most dangerous substance known to man because of its use in nuclear power plants which are seen as inherently dangerous and its potential as a catalyst for nuclear weapons proliferation.

Possibly it is the confusion of these two issues that has led to sensational exaggerations of plutonium toxicity. A 1989 paper by Bernard L. Cohen states: Pu hazards are far better understood than [those from insecticides or food additives], and the one fatality per 300 years they may someday cause is truly trivial by comparis

Re:.... Duh?

[Beryllium Sphere(tm)]

>I thought carbon dioxide sublimates, as in goes from solid to gas with no liquid step. Or, if it has a liquid stage, its only under very specific conditions of temperature and pressure.

It's pressure that makes the difference. At atmospheric pressure CO2 doesn't have a liquid phase. At higher pressures it does. In fact, the way you make dry ice (at least used to be) taking the pressure off some liquid CO2, letting some evaporate to chill the rest into a solid.

The proposed power plants operate at high pressure including the exhaust stream. So all you need to do is cool the exhaust and you have liquid CO2.

Lake Nyos in Cameroon

[SeanDuggan]

For sake of reference, the suffocation incident was at Lake Nyos in Cameroon and is documented at http://www.snopes.com/horrors/freakish/smother.asp . 1,746 people killed in a matter of minutes... evidence of how scary Mother Nature can be. Although, to be fair, death was apparently very swift and likely painless.

No, global warming is real

[lothar97]

Even the Bush administration finally snapped out of their denial:

the Bush administration has acknowledged that Earth is warming, and that the most likely cause is burning fossil fuels. The "U.S. Climate Action Report" acknowledged that global warming would "most likely" destroy alpine meadows, barrier islands and coral reefs. It may also cause the disintegration of southern forests. In the West, a decline in snow cover is expected to worsen water problems.

http://whyfiles.org/updates/080global_warm/

What a rosy view of the future!

Re:unless you know...

[pclminion]

Well this would be a problem if humans produced any real quantity of co2....the thing is 300 gigtons of co2 is produced a year from natural causes and humans only produce 6 gigtons

NO. 300 gigatons of CO2 cycle through the environment every year. In a closed cycle.

But every year, humans add an extra 6 gigatons to that cycle that was not there the previous year. We do this by taking carbon from deep underground (in the form of oil) and burning it to release that CO2 to the atmosphere.

Natural processes do not change the global CO2 balance, at least not on the short time scales that humans are capable of changing it.

Much more hazardous on an immediate basis.

[Ungrounded Lightning]

How is this diffrent then toxic waste from nuclear plants being stored under ground....

Much more hazardous, especially on an immediate basis.

Liquid CO2, pushed down injection wells under pressure, occasionally springs a leak. When this happens you suddenly get a giant bubble of CO2 on (and in) the ground, displacing the oxygen and killing everybody and everything (even plants if it persists in the soil long enough) for miles around.

This has happened when CO2 injection was used to pressurize oil wells to squeeze more oil out of the gound.

A similar phenomenon happens naturally (though fortunately VERY rarely) when largely CO2 volcanic gasses vent into a deep still lake (such as in a volcanic crater). The gasses disolve, carbonating the lower waters. Then suddenly something disturbs the water and some of the carbonated water comes up and starts to bubble - rapidly "turning over" and boiling out the CO2 in the rest of the lake in a matter of minutes and releasing a similar ground-hugging toxic bubble.

Think of a shaken soda can the size of Lake Tahoe.

if we continue storring all this wouldn't eventually run out of place to put it?

Nuclear, at least, takes up very little space and decays over years/centuries/millenia (depending on the isotope - generally the hotter the faster). Some of its components are also useful and can be separated out and put to work. Others can be "burned" in nuclear reactions into less hazardous and/or more useful material.

That's not to say it's safe or good stuff. Some of it is horrid. But "running out of room" isn't the problem. (Keeping it in its room until it promises to be a good little kid and MEANS it is the problem.)

Re:Methanol Power Plants?

[TheFlyingGoat]

No politician? Granted, $7.2 million isn't a huge amount of money, but it was enough for Bush to bring it up during the debates. I think the fact that it would increase agriculture jobs is just as important as helping the environment.