Coal or Nuclear: which do you prefer

[Ogie Oglethorpe]

Nuke: great for base demand

Coal: great for peak demand


75% Nuke

25% coal (or cogen trash burners or comb etc.)

[Kuciwalker]

I prefer burning babies

[Ogie Oglethorpe]

Originally posted by Kuciwalker
I prefer burning babies

A waste of perfectly good food.

[Thue]

Originally posted by Ogie Oglethorpe
Nuke: great for base demand

Coal: great for peak demand


75% Nuke

25% coal (or cogen trash burners or comb etc.)

Actually, coal is usually base load (like nuclear). See for example http://en.wikipedia.org/wiki/Base_load_power_station

[MichaeltheGreat]

Coal sucks for peaking - coal is very poor at handling short term load swings.

[General Ludd]

I prefer black outs.

[lord of the mark]

Originally posted by MichaeltheGreat
Coal sucks for peaking - coal is very poor at handling short term load swings.

IIUC nuke isnt much better. Peaking units today are typically natural gas, arent they? Ideally in time we will have solved storage problems adequately that we wont have to rely so much on peaking units.

[lord of the mark]

Originally posted by MichaeltheGreat


Only in a relatively small scale, and only in comparison with retail rates or with some form of green power subsidy/premium. If you're looking at utility scale base load generation (roughly 200MW+ combined cycle), wind doesn't even come close on a cost basis over a 20 year lifetime, and the number of potential sites remaining for commercial or utility scale generation is real limited.

nonetheless the amount of wind power generated is increasing, and the cost is decreasing. You can increase the amount even without new sites as you replace older less efficient plant with newer. And as you increase efficiency new sites become economic. Also as you increase the number of sites, you can offset somf of the reliability issues. YOuve still got peaking problems.

[MichaeltheGreat]

Originally posted by lord of the mark


IIUC nuke isnt much better. Peaking units today are typically natural gas, arent they? Ideally in time we will have solved storage problems adequately that we wont have to rely so much on peaking units.

Coal and nukes are effectively the same - operating protocols are to not bank cycle them for any form of peaking. Nukes can cycle output faster than coal in fact, but operationally, you'd never do that for safety and regulatory reasons.

After those two, oil is better, then conventional hydro, then combined cycle gas turbines, simple cycle gas turbines, and pumped storage hydro represent that rest of the hierarchy of load-responsive generation.

I don't think storage technology will impove enough in even another hundred years to make much difference in peaking applications. Incremental costs are a huge barrier.

[Whoha]

coal, I have little faith in our government's/private sector's ability to actually secure a nuclear plant.

[Sava]

Originally posted by MichaeltheGreat


There are three big problems with photovoltaics, but they're still real useful in a smaller commercial/specialty/ag pumping/residential application.

The biggest problem is low-voltage DC generation. Inversion and step-up losses to get into primary distribution or any transmissions systems are horrible (up to 28%).

Secondary is the relative rarity/toxicity of photovoltaic contituents - Lanthanide metals, phosporus, arsenic and such aren't real fun to mine, transport, mix and dispose of after their useful life.

Third is lifetime - photovoltaic substrates are damaged over time by UV rays, exposure to oxygen and corrosives in the air and internal heat, so efficiency and output drop over time after about 10 years.

Technology developments will improve these problems somewhat, especially the third area, but not a whole lot overall.

Do you think the technology has potential with regards to residential or small scale commercial use?

If the problems you speak of can be overcome (can they?), do you think PV's will become a popular alternative to "dirtier" forms of energy?

[Flubber]

Originally posted by Thue


So lets assume state of the art coal plant, without CO2 sequestation (which as I understand it has not been tried in practice yet).
.

Incorrect understanding. CO2 is being used extensively in the Weyburn project in Canada. They are actually shipping CO2 from the US and the largest limitation is the unavailability of pure CO2. Pure CO2 assists in oil recover but any Nitrogen would reduce recovery

[MichaeltheGreat]

For your first question, definitely, as the technology stands now, there's a good residential use, especially in the southern to central, summer-peaking parts of the country. It's a great application in Arizona, not that great in Wisconsin.

Small commercial applications are a little dodgier, as a lot of small commercial loads are lighting driven, so your hourly generation efficiency curves and demand curves don't match that well, but photovoltaics make a good peak shaving resource as a supplement to regular source of supply, again, especially in the sun belt where summer cooling loads are a big peak driver.

If you're out in the sticks a bit, where you need private water wells, it's a great application. I have a couple of parcels in New Mexico where I would do a photovoltaic system to handle well pumping and on-site water treatment when it's time to drill wells and install storage tanks. Same thing for offsetting air conditioning/circulation and refrigeration loads in the summer.

The problems aren't fatal, they're just disadvantageous to larger scale use of photovoltaics. Given the physics of photovoltaics, I don't think there will be radical improvements, but there should be some gradual improvement over the years to improve the marginal cost efficiency of photovoltaics and enlarge their niche of potential applications.

[Dinner]

Coal adds CO2, acid, heavy metals, and mercury (which is a heavy metal but deserves special notice since it is so high in coal and causes such ecological harm) while nuclear power does none of those things. Nuclear is the future and it is the only way we can create massive amounts of power which is completely scalable to demand, is usable 24/7, and doesn't create any green house gases. Spent fuel rods are 100% recyclible.

People need to understand that there is no such thing as risk free energy; there is only risk minimized energy and nuclear power is risk minimized energy. It is far easier to recycle and/or store spent fuel rods then it is to capture CO2 and control global climate change. Coal is an extremely dirty and dangerous energy source where as nuclear is not. Wind, solar, and geothermal are nice but expensive (especially solar) niche power sources which are only suitable for certain areas and which are not nearly reliable enough to be used for base load. If you always want the lights to turn on when you flip the switch and you don't want to make global climate change worse then your only options for massive amounts of power are hydro or nuclear. There are no new rivers to dam. Thus nuclear is our only option.

[Drogue]

Nuclear, by a mile. However I think wind and various other methods could be used more, to get close to a decent amount of provision. That combined with increased nuclear should be able to slow the use of fossil fuels