Nuclear Fusion one step closer...

[Wombat]

Originally posted by az
Efty, how warm does it get where you live? is AC really required?

AZ

Hell yes, AC is required. New York is hot and humid, and the urban heat keeps you up over 100F.

I've lived in New Jersey and St. Louis, Missouri. Both of these places have about 4 months of the year where the temperature/humidity exceed the maximum operating conditions of every piece of sophisticated electronics. So, "Do you need AC?" is pretty much asking, "Do you need a computer?"

[az]

Oh, and Herzlichen Glückwunsch zum Geburtstag

AZ

[az]

Wombat, I mean no offense, it just seems to me that most houses built in the USA are of a quite cheap quality (ours are horribly expensive, though), and many people have AC not because they need it, but because it is convenient, much like almost nobody needs a SUV or even a pickup.

EDIT: Of course there might be places where nobody would want to live without AC - that's why I was asking

AZ

[K6-III]

Very humid in Minnesota with our lakes. AC is a must.


I'll have to agree that houses in the USA are build not for qaulity or efficiency, but for maximum size...

[K6-III]

Originally posted by K6-III
How about the energy that can be developed by pumping cold water to the surface near the equator and using the Delta T to spin a turbine???

Didn't remember what it was called initially. I was thinking of an OTEC.

[efty]

When I asked Brian about his study i was refering to Cyprus not NY. I never stayed in NY during the summer.

I can talk about Cyprus. Costal areas get their fair ammount of humidity but not to the NY levels. Temperatures can reach 45 cel.
I think AC is a must during the summer in Cyprus. This was not the case a few years ago. It gets worse and worse every year. I used to drive for 45 min to go to work and my car has no AC. It feels like you are being cooked alive. Open the window and more hot air gets blown in your face. I had to struggle every morning to find a shaded parking spot so that when I left at 4pm the car was at a bearable temperature.

I think in the house tou can get through without an AC depending where you are and how well insulated it is. If you keep the house locked after you leave in the morning, when tou come back it is prety cool. If you have people comign in and out then your house is going to be a furnace.

[KvHagedorn]

Originally posted by Brian Ellis
Farnsworth's ideas round the Fusor have not been suppressed. There is no intellectual property involved in them, now, as the patents fell into the public domain many years ago. His patents and designs are still available and, if they were viable, they could be exploited by anyone. The problem is that they are not viable, i.e., IF they produced free neutrons, they would require more energy to do so than would be produced (as in most other fusion systems). However, the real problem seems to be that other experimenters have not been able to duplicate his supposed findings.

BTW "safe energy" is really an oxymoron. Energy, in any reasonable form of power, can never be safe. One of the potentially most dangerous is the hydroelectric dam. Since the 39-45 war, it is estimated that over 2,000 persons per year, on an average, are killed by water accidentally escaping from HE dams in some way or another. This makes Chernobyl look like child's play, regrettable though it was. I have always said that I'd much rather live next door to a nuke power station than downstream from a major dam.

You know, the genius of Farnsworth originated in his attitude that there was nothing that could not be done. How many people have been discouraged by those who say his ideas are not viable? If we went on the assumption that he did in fact, as reported, achieve a sustained reaction, it might be much more productive to try a bit harder to find out how he did it. The man is not without his credentials, you know.

The solution to the hydroelectric problem is to NOT live downstream of a dam. Hydroelectric is probably the best all-around energy source. It is absolutely clean, relatively infinite, and after the original capital investment, very cheap to produce. Dams are also necessary to reduce flooding in some areas and to provide a consistent water supply. It's nice to have lakes for recreational purposes as well.

[az]

Sorry, there aren't enough dams that would be needed for anything else than producing electricity, and those big dam projects do bring a lot of problems with them (social and environmental, apart from the danger of breaking).

AZ

[Dr Mordrid]

Brian;

FYI the US Livermore and Los Alamos labs have been and still are involved in inertial electrostatic confinement fusion research and has come up with some practical uses. One is as a neutron source for such things as land mine detection. Its advantage over isotopic Californium neutron sources is one of safety: it can be turned OFF and there is no danger of an accidental release/spill. It also has low power requirements compared to some other electronic neutron generators.

Alternative confinement systems to the (IMHO failed) magnetic schemes aren't limited to IEC. There is also the work being done on PFX-I: Penning Fusion Experiment-Ions, based on traps using space charge confinement. This avoids the internal electodes that can limit the power levels in Fansworths IEC.

http://www.lanl.gov/projects/pfxi/

PFX-I is funded through at least 2004.

Dr. Mordrid

[Brian Ellis]

OK, guys: a lot of answering, from the end backwards.

I cannot agree with KvH about hydroelectricity without a lot of ifs and buts. There are 4 kinds of HE installations. The least harmful is the type where there are no dams (e.g., Niagara), using natural differences of level or where there is a large river water volume with a weir to channel it (using different turbine designs, of course). Correctly designed systems of this type are generally OK. Pumped HE systems between two natural lakes at different altitudes are a very useful way of storing energy (e.g., pump up at night, when there is surplus electricity and generate during the peak day periods). The third type is the high Alpine dam, such as the Grande Dixence, several hundred meters high, jammed in a narroe valley. This is dangerous, as has been shown umpteen times, although satellite monitoring has reduced the risk of collapse due to seismic effects. (The Rawyl dam was rapidly but safely emptied a few years ago to avoid such a catastrophe: one of its anchors had moved a few cm; a few more and it would have given way). The worst type is typified by the 3 Gorges in China. 180 m high, it will create a retention lake 600 km long. It is built in a seismic area with unstable limestone gorges in the lake area (when I visited the site, during a UN mission, I actually witnessed a small landslide into the Yangtze and I have a photo, as proof). 2 million people, mostly farmers, have had to be evacuated from some of the most fertile land in China and have been rehoused in towns, where they have no skills. China's largest city, Chongqing, will discharge the raw sewage from 27 million people directly into the still lake where there will be no aerobic decomposition, like now. Eventually, this will silt up the dam which will become useless. Countless unique biotopes will be destroyed and millions of wader birds will have their habitats equally destroyed. Geologists predict that the weight of the water in the lake could cause chunks of limestone mountain to fall into the lake causing a tidal wave which will overflow the dam, causing a catastrophe in Yichang, a city of 2 m inhabitants on the banks of the river, just 20 km downstream. Let's hope this never happens but the risk is high., quite apart from the certain environmental catastrophe (many fish species will disappear because a river fish can never survive in a stagnant, polluted lake; the population is partially dependent on the fish for animal protein). To cap it all, two large river dams, constructed using modern engineering techniques in the 1970s were built, under similar conditions a few 100 km N of the site, on a smaller river. Both have given way because of natural phenomena causing a total death toll variously estimated between 75,000 (the official figure) and 250,000 (the popular figure given by regional inhabitants), probably the worst death toll from bursting dams. Other examples of environmental problem dams have been found on the Columbia River, Aswan, Kariba. Other examples of human catastrophes have been Fréjus (arch dam collapse), Mattmark (glacier falling in lake while still under construction) and one very bad one in Italy whose name escapes me for the moment (half a mountain fell into the lake) etc. No, there is always a large risk associated with HE schemes.

Efty: the proposed system does not include batteries. It's all done with intelligent electronics. The DC from the solar cells is converted to AC using an inverter, at 240 V 50 Hz, synchronised to the incoming mains. When the household demand exceeds the capacity, the extra is taken from the mains and I pay the normal rate. When the demand is less than the capacity, I sell the surplus electricity back to the EAC at a subsidised rate, higher than I pay. So, I can have all the AC units running that I want. In fact, a running 9 kBTU AC unit is not very greedy, only ~800 W. It is the start-up period that needs lots of juice, so I could run 3 at any one time, provided that I didn't start them simultaneously. In fact, we rarely run more than two ACs at any one time.

I agree that with modern housing, AC is essential here. We had 47.3 deg C with low RH a few years ago, but 45 C is every year. Typically, the RH is about 25 - 30% (we are away from the coast, where it rises to over 50%, which is hell at over 40 C). Traditional mud brick housing with tiny windows is actually better than modern houses with large windows, despite reflective double-glazing. Aluminium window and door frames don't help, either. However, the real thermal catastrophe in modern housing is the massive steel reinforced anti-seismic skeleton. On a hot day, you can feel the difference in temperature between the skeleton (even interior elements that never see the sun) and the insulated brickwork. It's the price we pay to ensure our safety in an earthquake-prone country.

[GNEP]

Oh yeah, to add another possible part to our future energy portfolio: the solar chimney. I'm not sure on this, but I think that there is a pilot being built in Australia somewhere.

Basically, you lay a massive "floor" of black material or maybe glass about a metre off the ground, with just support struts underneath, in a solid circle about a kilometre across. In the centre you have a really (and I mean really really) tall hollow tower with a turbine near the bottom and open to the atmosphere at the top.

The sun will heat up the air under the "floor" and so it will want to rise and be displaced by the cooler air surrounding the "floor". The only place it can go is up the tower, which it does, driving the turbine.

Apparently quite effective in theory, but requires massive dimensions to work well (and use the really large temperature differential with the air high up). Also needs a sunny country with lots of space. So Australia then...

Here's a nice link:

http://www.sbp.de/de/html/projects/solar/aufwind/pages_auf/techno.htm

EDIT: having thought about it, I think the pilot is in Spain.

[Brian Ellis]

GNEP

Yup! The pilot is in Spain. The Australian one is a project that I think has received planning permission. Effectively, if I remember correctly, it is a 27 km2 circular greenhouse which is open around the periphery and has a 1 km high steel chimney in the centre. On the floor is a black alu honeycomb to absorb as much short wavelength solar IR as possible and use it to heat the air, creating convecting conditions up the chimney in the form of a really howling hot gale, with turbines mounted in the chimney. I'm not sure of the figures, but I think they are hoping to get 5 MW (~20% thermal efficiency). There are also water tanks involved and I think they hope to store some of the heat so that it works 24/24.

I also seem to recollect that the Israelis are experimenting with tall chimneys that are cooled by spraying with water, creating a downdraught to achieve the same end.

The Oz project requires as much ground as many a medium-sized town, so it wouldn't work very well in Monaco or the Vatican!!!!!

[GNEP]

Indeed - the sheer size of these things limits their usefulness in e.g. western europe.

I am sure the US has probably got space for some though.#

And yes, the water in some of the designs is to produce 24-hour electricity.

[az]

Isn't wind a risk with such tall structures?

AZ

[GNEP]

Yes, but nothing insurmountable - you have plenty of room around them to tether with wires you see