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Solar panel made with ion cannon is cheap enough to challenge fossil fuels

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Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#151

Post by ajuc »

jsilence wrote: post #149
ajuc wrote: post #144

Earlier quoted context omitted.

Germany also shut down sth like 60% of their nuclear power plants in response to Fukushima hysteria, even thought in central Europe there are no tsunami, nor big earthquakes. Then, January/February this year cold snap happened, and they had to buy power from neighborns that still have regular obsolete power plants, because they couldn't provide enough energy for themselves. Green energy means you hope for good weathe…

Sorry, but you are not correct. During the very cold days this winter it was very sunny. Because of this, Photovoltaic could compensate. It went through the local media, that even though most of the nukuhlar powerplants were shut down, we could still export (!) electricity to our neighours. For exmple to France, where they are heating a lot with electricity and had a shortage because of the cold. Bazinga!

Thanks. I remember reading it the way I've posted aboove, but now I can't find that article, and I've found corrections all over the web: http://enenews.com/scandal-germany-not-restarting-nuclear-re...

EDIT: one source http://rt.com/news/germany-reactors-cold-weather-927/

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#152

Post by pjscott »

DennisP wrote: post #145
pjscott wrote: post #131

Earlier quoted context omitted.

Other problems with building nuclear plants (or any other type of plant that requires large steam turbines) in the desert include: * Difficulty cooling. If you build next to an ocean or river, you can just use some of that water to provide the cold end of the temperature differential that you're using to generate power. Deserts are trickier, and more expensive. * Transportation. If you build next to navigable waterwa…

Some of the GenIV designs don't require water cooling.

They all require some kind of cooling. Fundamentally, a nuclear reactor sets up one end of a temperature differential that you can use to do work:

http://en.wikipedia.org/wiki/Thermodynamic_cycle

Water just happens to be a particularly convenient coolant.

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#153

Post by pjscott »

jurjenh wrote: post #101
r00fus wrote: post #63

Earlier quoted context omitted.

Forget supercondictivity, what about HVDC [1]? HVDC can be as efficient as 97%, compared with the US average of 93%. That 4% "inefficiency tax" would likely pay for long-haul HVDC connectors (as outlined in one of Obama's 2008 energy proposals) within years. [1] http://en.wikipedia.org/wiki/High-voltage_direct_current#Adv...

New Zealand has had a 600V HVDC link from the South Island to the North Island for quite some years - most of the power is generated by the hydro lakes in the south, then delivered via a 610km link to a substation in the north, where it is fed into the normal high-voltage transmission grid. http://en.wikipedia.org/wiki/HVDC_Inter-Island So it is a proven technology to have this as a long distance link (been in operat…

HVDC definitely makes sense for connecting islands together. The cable goes underwater, and in water, the capacitance of the cable is much increased by the greater dielectric constant of the water, which makes AC transmission less efficient.

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#154

Post by jurjenh »

nitrogen wrote: post #141
jurjenh wrote: post #101

Earlier quoted context omitted.

New Zealand has had a 600V HVDC link from the South Island to the North Island for quite some years - most of the power is generated by the hydro lakes in the south, then delivered via a 610km link to a substation in the north, where it is fed into the normal high-voltage transmission grid. http://en.wikipedia.org/wiki/HVDC_Inter-Island So it is a proven technology to have this as a long distance link (been in operat…

I'm curious where you get the "600V" number from -- is that 600 volts? According to the Wikipedia page you linked the system uses "+270kV and −350kV", which is in the range I would expect. Maybe you meant 620kV, the difference between +270kV and -350kV?

My apologies, that must've been some confusion in my mind... it was a 600MW HVDC link... although it is higher now, and works are underway to bring it up to somewhere near 1.4GW.

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#155

Post by DennisP »

pjscott wrote: post #152
DennisP wrote: post #145

Earlier quoted context omitted.

Some of the GenIV designs don't require water cooling.

They all require some kind of cooling. Fundamentally, a nuclear reactor sets up one end of a temperature differential that you can use to do work: http://en.wikipedia.org/wiki/Thermodynamic_cycle Water just happens to be a particularly convenient coolant.

I'm aware of that, but water isn't the only convenient coolant. Molten salt, sodium, molten lead, and helium are other options.

Water has some disadvantages. It's a good neutron moderator, but with its low boiling point you have to keep it under a lot of pressure (160 atmospheres for most light-water reactors). That means you need very strong, thick steel, and a huge oversize containment dome, since if a pipe breaks, the steam will flash into 1000 times as much volume. Then some of it will split, and you'll be at risk of a hydrogen explosion, which is what we all saw at Fukushima.

Molten salt, on the other hand, works at atmospheric pressure, and if something leaks it just drips out and cools into rock.

Sodium has a disadvantage in being reactive with oxygen and water, but it also works at atmospheric pressure. The integral fast reactor design uses a big pool of sodium, which provides so much thermal inertia that Argonne was able to switch off the cooling system entirely, and the reactor just quietly shut down.

Either design works at higher temperatures than LWRs, giving better thermodynamic efficiency.

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#156

Post by justincormack »

stromstad wrote: post #146
justincormack wrote: post #57

Earlier quoted context omitted.

Germany has a plan to use Norway as a huge energy store, adding pumping capacity to the hydroelectric plants.

Really? I would be very interested in reading more about this. Got any sources? (Preferably in English or Norwegian ;) )

There is a presentation here http://norwegen.ahk.de/fileadmin/ahk_norwegen/Dokumente/Pres... And an article here about building the necessary cabling http://www.reuters.com/article/2010/08/27/us-norway-seacable...

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#157

Post by danielharan »

greedo wrote: post #137
danielharan wrote: post #117

Earlier quoted context omitted.

Turbines kill fewer birds than coal plant smokestacks. Newer, bigger ones move more slowly, killing fewer birds as well as being quieter. They also produce more power per area. As for the view... well, you can't please everyone.

Actually that's incorrect, at least for centralized wind farms: http://www.indiana.edu/~spea/pubs/undergrad-honors/volume-4/... The key takeaway from that thesis is: "As determined in the risk characterization, a centralized wind farm does have a greater impact on avian mortality than the coal fired- power plant. "

Correct link: http://www.indiana.edu/~spea/pubs/undergrad-honors/volume-4/...

The thesis examines only Fowler Ridge, which mostly has 1.65MW Vestas v82 with a 41m blade length and hub height of 70m. The latest I could easily get specs for is a 3MW Vestas: 56m blade length, 84m hub. Higher, more efficient, and most importantly: slower which kills fewer birds.

Last year they introduced a the V164 at 7.0MW: http://en.wikipedia.org/wiki/Vestas

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#158

Post by kragen »

dctoedt wrote: post #80
tsotha wrote: post #70

Earlier quoted context omitted.

That's true, but does this make the fuel last longer, and anyway what are fuel costs as a percentage of total operational costs? My impression is it doesn't make sense to operate a nuclear reactor at less than full power.

> does this make the fuel last longer Yes. Heat is generated by fission of fissile material such as uranium. Fuel rods have X amount of fissile material in them. Higher power -> faster depletion of the fissile material. > what are fuel costs as a percentage of total operational costs? Around 30%, according to the Nuclear Energy Institute. This compares with 80% for coal, natural gas, and oil.[2] > My impression is it…

Some nuclear plants are designed to be throttled up and down as needed; others are not and can not. Your experience with naval reactors does not generalize to all civilian reactors.

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#159

Post by FeministHacker »

TeMPOraL wrote: post #31
jsilence wrote: post #9

Earlier quoted context omitted.

Transportation of electricity around the globe is not neccessary. Electricity usage is considerably lower during nighttime. Thus solar and wind fit in with our natural rhythm quite nicely. And it is also produced near the place there it is being consumed. Another plus. But still the author is right, we need ways to store electricity and we will also need a much more flexible grid than the one we have today. The neo l…

> Thus solar and wind fit in with our natural rhythm quite nicely. It's not that nice, because power output from wind/solar plants is random (depends on things like cloud cover or wind strength) and it causes problems in power grid, where power demand must meet the supply exactly, or bad things will happen. "Without Hot Air"[1] covers this, and other renewable-related issues quite nicely and with real data. I recomme…

Whilst on a small scale they are very random, there are some good studies (sadly I don't have the references with me) that show that over large areas, they actually become quite predictable - so this is less of an issue than people think if you have enough coverage

Re: Solar panel made with ion cannon is cheap enough to challenge fossil fuels

#160

Post by wlesieutre »

i2pi wrote: post #118
wlesieutre wrote: post #90

Earlier quoted context omitted.

Steering a car full of gyroscopes in fast moving traffic? Sign me up!

http://en.wikipedia.org/wiki/Gyrobus

That's really cool, I'd never heard of these. I imagine the flywheels are horizontal so that the bus can turn without trying to change their angular momentum, but I wonder if there's any effect on banked curves or going up hills.
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