Solar Power

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BrownTown

Diamond Member
Dec 1, 2005
5,314
1
0
if only fussion worked and we could get all the energy we needed from seawater...

I mean, we got it to work in bomb form 50 years ago, theres gotta be someway to harness it without blowing stuff up. If only we could find someway of containing a reaction the temperature of the sun :p
 

Meuge

Banned
Nov 27, 2005
2,963
0
0
Originally posted by: BrownTown
if only fussion worked and we could get all the energy we needed from seawater...

I mean, we got it to work in bomb form 50 years ago, theres gotta be someway to harness it without blowing stuff up. If only we could find someway of containing a reaction the temperature of the sun :p
We already do. The question is how to sustain the reaction without destroying the container, and how to better harness the energy.
 

MCsommerreid

Member
Jan 3, 2006
98
0
0
Originally posted by: Meuge
Originally posted by: BrownTown
if only fussion worked and we could get all the energy we needed from seawater...

I mean, we got it to work in bomb form 50 years ago, theres gotta be someway to harness it without blowing stuff up. If only we could find someway of containing a reaction the temperature of the sun :p
We already do. The question is how to sustain the reaction without destroying the container, and how to better harness the energy.

Keeping it from destroying the container is easy, and has been done several times. It's the harnessing the energy and creating a continuing chain reaction that's the pain in the butt. Hopefully that will be solved and nuclear fusion reactors can be built all over without too much bitching and moaning. They'd probably solve the hell out of the energy problem, especially if more racey electric cars are developed.
 

Meuge

Banned
Nov 27, 2005
2,963
0
0
Originally posted by: MCsommerreid
Originally posted by: Meuge
Originally posted by: BrownTown
if only fussion worked and we could get all the energy we needed from seawater...

I mean, we got it to work in bomb form 50 years ago, theres gotta be someway to harness it without blowing stuff up. If only we could find someway of containing a reaction the temperature of the sun :p
We already do. The question is how to sustain the reaction without destroying the container, and how to better harness the energy.
Keeping it from destroying the container is easy, and has been done several times.
You're misunderstanding me. Keeping plasma in the tokamak is one thing, but the high eV neutrons that are produced by the reaction cause the breakdown of the physical walls outside the magnetic bottle. Assuming the reaction can be sustained, it'll become a problem relatively quickly.
Originally posted by: MCsommerreidIt's the harnessing the energy and creating a continuing chain reaction that's the pain in the butt.
We really really really really don't want a chain reaction... we want a continuous reaction, but one that's not self-sustaining.
 

K1052

Elite Member
Aug 21, 2003
53,121
47,292
136
Originally posted by: Meuge
Originally posted by: MCsommerreid
Originally posted by: Meuge
Originally posted by: BrownTown
if only fussion worked and we could get all the energy we needed from seawater...

I mean, we got it to work in bomb form 50 years ago, theres gotta be someway to harness it without blowing stuff up. If only we could find someway of containing a reaction the temperature of the sun :p
We already do. The question is how to sustain the reaction without destroying the container, and how to better harness the energy.
Keeping it from destroying the container is easy, and has been done several times.
You're misunderstanding me. Keeping plasma in the tokamak is one thing, but the high eV neutrons that are produced by the reaction cause the breakdown of the physical walls outside the magnetic bottle. Assuming the reaction can be sustained, it'll become a problem relatively quickly.
Originally posted by: MCsommerreidIt's the harnessing the energy and creating a continuing chain reaction that's the pain in the butt.
We really really really really don't want a chain reaction... we want a continuous reaction, but one that's not self-sustaining.

The neutron capturing element of the reactor is what they refer to as the "blanket". Supposedly this will be comprised of lithium-6 which will capture the neutrons and produce tritium.
 

TheSlamma

Diamond Member
Sep 6, 2005
7,625
5
81
Originally posted by: Aimster
If you generate more electricity than you use.

you get money :)

Actually most power companies you can only go to zero bill.

 

chcarnage

Golden Member
May 11, 2005
1,751
0
0
Solar energy if collected in a decentralised way should be used to heat water because that's more efficient than generating electricity, except if the house in question is not connected to the power supply system or if it is at a really warm location.
 

catnap1972

Platinum Member
Aug 10, 2000
2,607
0
76
Originally posted by: TheSlamma
Originally posted by: Aimster
If you generate more electricity than you use.

you get money :)

Actually most power companies you can only go to zero bill.

I'd assume the leftover would end up as a bill credit (though knowing the power company, a "Hey, thanks for generating some free juice for us" response wouldn't surprise me)

 

Meuge

Banned
Nov 27, 2005
2,963
0
0
Originally posted by: catnap1972
Originally posted by: TheSlamma
Originally posted by: Aimster
If you generate more electricity than you use.

you get money :)

Actually most power companies you can only go to zero bill.

I'd assume the leftover would end up as a bill credit (though knowing the power company, a "Hey, thanks for generating some free juice for us" response wouldn't surprise me)
He's wrong. In most places the electrical companies are obligated by law to pay you back at the same rate as they charge you.
 

MadRat

Lifer
Oct 14, 1999
11,999
308
126
Originally posted by: Meuge
Originally posted by: MadRat
I think the wind is the better alternative. When they get useful (1-1.5kW) windmills down to $1500 (just for the windmill not the inverter and batteries) then I'm in.
They are really huge and ugly though. The great thing about roof solar panels is that they're totally unobtrusive.


Those cylindrical fans, if positioned atop a roof ridge, would work excellent. Slim, quiet, the roof forces airflow into them. Its the solution to the tall, ghastly windmills of tradition.
 

MadRat

Lifer
Oct 14, 1999
11,999
308
126
Originally posted by: Meuge
Originally posted by: catnap1972
Originally posted by: TheSlamma
Originally posted by: Aimster
If you generate more electricity than you use.
you get money :)
Actually most power companies you can only go to zero bill.
I'd assume the leftover would end up as a bill credit (though knowing the power company, a "Hey, thanks for generating some free juice for us" response wouldn't surprise me)
He's wrong. In most places the electrical companies are obligated by law to pay you back at the same rate as they charge you.

I'm pretty sure TheSlamma is right, a minority of states mandate payments for surplus energy production.
 

rahvin

Elite Member
Oct 10, 1999
8,475
1
0
Originally posted by: Meuge
He's wrong. In most places the electrical companies are obligated by law to pay you back at the same rate as they charge you.

Most? Why not prove that, last I looked there might have been one or two. The vast majority of states, as I remember it, are on net-metering which only takes the meter to zero at the end of the year plus a nominal line maintence fee per month.
 

MCsommerreid

Member
Jan 3, 2006
98
0
0
Originally posted by: Meuge
Originally posted by: MCsommerreid
Originally posted by: Meuge
Originally posted by: BrownTown
if only fussion worked and we could get all the energy we needed from seawater...

I mean, we got it to work in bomb form 50 years ago, theres gotta be someway to harness it without blowing stuff up. If only we could find someway of containing a reaction the temperature of the sun :p
We already do. The question is how to sustain the reaction without destroying the container, and how to better harness the energy.

Keeping it from destroying the container is easy, and has been done several times.
You're misunderstanding me. Keeping plasma in the tokamak is one thing, but the high eV neutrons that are produced by the reaction cause the breakdown of the physical walls outside the magnetic bottle. Assuming the reaction can be sustained, it'll become a problem relatively quickly.

I coulda sworn there was already a set up of some kind that prevented this, allowing for repeated reactions, though I could be entirely mistaken.
Originally posted by: MCsommerreidIt's the harnessing the energy and creating a continuing chain reaction that's the pain in the butt.
We really really really really don't want a chain reaction... we want a continuous reaction, but one that's not self-sustaining.

You're right. That's what I meant but didn't deliver properly, kind of combining the two. Ignore that "chain" part.
 

rahvin

Elite Member
Oct 10, 1999
8,475
1
0
Neutron build up is real, but the systems are designed to withstand it, they have blanket of high neutron absorbing material on the inside. ITER's reactor core (which should run nearly continously) is slated for about 10 years before the alpha radiation destorys the vessel. The neat thing is you can take it appart and leave it sitting in a parking lot (alpha radiation isn't very dangerous, your skin can block the neutrons) and it will de-energize in a few years.
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
1
0
I wonder how much money goes into developing fusion reactors, probably less then goes into Intel trying to push Itanium processors on us all...
 

silverpig

Lifer
Jul 29, 2001
27,703
12
81
Originally posted by: zephyrprime
Some of the figures being bandied about are way too high. I did a quick search on the web and it seem like solar panels are still at only abouyt 18% efficiency.

http://www.jetro.go.jp/en/market/trend/topic/2004_11_mtv.html
http://www.cnn.com/2003/TECH/biztech/04/14/better.photovoltaics.ap/

18% is an improvment over what it was 10 years about but the technology still has a long way to go before it hit 50%. Nanotech may help but it's just not here yet. I think polymer solar panels hold more promise. They have horrible efficiency but they should be relatively cheap to make.

That's a little more accurate I think.
 

silverpig

Lifer
Jul 29, 2001
27,703
12
81
Originally posted by: rahvin
Noone even questioned your first post so I will. Meuge, Show me a single solar panel available for residential installation that gets better than 25% efficiency. That 50% efficiency was just a bullsh!t number.

You MIGHT be able to get a solar equipment for the prices you have been quoted but if you want it installed properly then you need a professional install (you don't want to fvck around when putting stuff on the roof of your home) and there is no way you can legally tie a solar installation into your electrical system without a qualified electrition doing it. Keep in mind that if you do this without a building permit and proper inspection you will void your insurance. And I haven't seen a professional install quote for less than $15,000 for a decently sized system and you really need $25K to get a system size that's worthwile. Until panel prices come down it's not worth bothering with it.

Whoa, take it easy on the guy. It's been said in this thread that research on 50% efficient solar cells is on the way. Yeah they don't exist now, but he openly admitted in a previous post that he only found 20-30% solar cells and that someone told him about 40-50%.

Secondly, I'm quite certain you can tie whatever you want into the power grid without being a qualified electrician. You just can't physically connect it before an inspection. How do I know? My dad built my parents' house, and did all the electrical work himself. He's not an electrician. He got it inspected, passed, and my parents are currently enjoying the electricity.
 

silverpig

Lifer
Jul 29, 2001
27,703
12
81
Originally posted by: rahvin
Neutron build up is real, but the systems are designed to withstand it, they have blanket of high neutron absorbing material on the inside. ITER's reactor core (which should run nearly continously) is slated for about 10 years before the alpha radiation destorys the vessel. The neat thing is you can take it appart and leave it sitting in a parking lot (alpha radiation isn't very dangerous, your skin can block the neutrons) and it will de-energize in a few years.

Except alpha radiation is not neutrons. Your skin will not block neutron radiation, and it is extremely dangrous.
 

rahvin

Elite Member
Oct 10, 1999
8,475
1
0
Originally posted by: silverpig
Secondly, I'm quite certain you can tie whatever you want into the power grid without being a qualified electrician. You just can't physically connect it before an inspection. How do I know? My dad built my parents' house, and did all the electrical work himself. He's not an electrician. He got it inspected, passed, and my parents are currently enjoying the electricity.

You do understand the difference between hooking up power draining devices and hooking up power generating devices to the grid? Apparently not, let me be the first to inform you that if it isn't done absolutely correctly you run the risk of killing a lineman by pushing juice into what a lineman could believe is disconnected lines. Get my drift?
 

Meuge

Banned
Nov 27, 2005
2,963
0
0
Originally posted by: silverpig
Originally posted by: rahvin
Neutron build up is real, but the systems are designed to withstand it, they have blanket of high neutron absorbing material on the inside. ITER's reactor core (which should run nearly continously) is slated for about 10 years before the alpha radiation destorys the vessel. The neat thing is you can take it appart and leave it sitting in a parking lot (alpha radiation isn't very dangerous, your skin can block the neutrons) and it will de-energize in a few years.

Except alpha radiation is not neutrons. Your skin will not block neutron radiation, and it is extremely dangrous.
Alpha radiation = helium nuclei. There are no natural powerful alpha emitters, so the energy value of alpha decay is usually low enough to be stopped by skin.

Beta radiation = free electrons. It can range from weak to quite strong. Trust me, you don't want any P32 around you. The upside of beta emitters is that they usually have pretty short halflives.

Gamma = electromagnetic = photons... can range from very weak to incredibly strong.

Neutrons = usually VERY high energy (takes a lot to knock a neutron out of a nucleus). High energy neutrons are VERY hard to stop, and they are HIGHLY ionizing and damaging due to their tremendous momentum (1000X the mass of an electron).
 

rahvin

Elite Member
Oct 10, 1999
8,475
1
0
Originally posted by: silverpig
Originally posted by: rahvin
Neutron build up is real, but the systems are designed to withstand it, they have blanket of high neutron absorbing material on the inside. ITER's reactor core (which should run nearly continously) is slated for about 10 years before the alpha radiation destorys the vessel. The neat thing is you can take it appart and leave it sitting in a parking lot (alpha radiation isn't very dangerous, your skin can block the neutrons) and it will de-energize in a few years.

Except alpha radiation is not neutrons. Your skin will not block neutron radiation, and it is extremely dangrous.

My mistake, it's been more than a decade since I had the courses. The article I read said the radioactivity released by the reactor core is not dangerous.
 

Meuge

Banned
Nov 27, 2005
2,963
0
0
Originally posted by: rahvin
Originally posted by: silverpig
Originally posted by: rahvin
Neutron build up is real, but the systems are designed to withstand it, they have blanket of high neutron absorbing material on the inside. ITER's reactor core (which should run nearly continously) is slated for about 10 years before the alpha radiation destorys the vessel. The neat thing is you can take it appart and leave it sitting in a parking lot (alpha radiation isn't very dangerous, your skin can block the neutrons) and it will de-energize in a few years.

Except alpha radiation is not neutrons. Your skin will not block neutron radiation, and it is extremely dangrous.

My mistake, it's been more than a decade since I had the courses. The article I read said the radioactivity released by the reactor core is not dangerous.
It is very dangerous, but because neutrons are large, and heavy, they quickly collide with molecules in the immediate vicinity of the reactor, thus the radiation is very much a local phenomenon.
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
1
0
yeah, but in terms of containment, they aren't any problem becasue they are blocked by pretty much everything. I don't even know if they can get far enough into your skin to even attack the living layers? So, they are much more a threat to machines then they are to people. And the reason people don't like radiation is becasue they feal it is a threat to them, so if fusion reactors dont produce radiation that hurts people then maybe they will get mroe populat support,...
 

Meuge

Banned
Nov 27, 2005
2,963
0
0
Originally posted by: BrownTown
yeah, but in terms of containment, they aren't any problem becasue they are blocked by pretty much everything. I don't even know if they can get far enough into your skin to even attack the living layers? So, they are much more a threat to machines then they are to people. And the reason people don't like radiation is becasue they feal it is a threat to them, so if fusion reactors dont produce radiation that hurts people then maybe they will get mroe populat support,...
Well, direct exposure to high-energy neutrons will kill you... easily.

On the other hand, they're not as hard to contain due to the fact that their penetrating ability is less than that of gamma. But they will deliver far more energy per unit volume.