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[GrizzlyAdamz]

That link you provided didn't give any concrete numbers. They said it gives a net energy gain 10 different ways, but didn't explain exactly how much, and also used a questionable definition of net energy- (compared to energy in xylose and H-splitting enzymes, not the energy that goes into creating those components as well).

Natural gas is yet another dead-end fossil fuel that wrecks the environment. It's nice that they aren't straight-up burning the stuff off when they tap wells, but we all know what fracking is.

Nuclear is good, (but here's something that blew my mind: peak oil? peak uranium. (peak everything)).

[Leafsnail]

We aren't going to completely run out of uranium in any reasonable timeframe, but it will become harder and harder to extract so a "peak" situation is possible.  It's already effectively happened in some countries.

[AlmightyOne]

From wiki

Another alternative to fast breeders is thermal breeder reactors that use uranium-233 bred from thorium as fission fuel in the thorium fuel cycle. Thorium is about 3.5 times more common than uranium in the Earth's crust, and has different geographic characteristics. This would extend the total practical fissionable resource base by 450%.[96] Unlike the breeding of U-238 into plutonium, fast breeder reactors are not necessary — it can be performed satisfactorily in more conventional plants.

[Leafsnail]

Thorium does have a lot of potential, my understanding was that it's less popular due to the fact you can't use it to make weapons.

[10ebbor10]

Thorium does have a lot of potential, my understanding was that it's less popular due to the fact you can't use it to make weapons.

It's also slightly corrosive and more expensive.

But yeah, Thorium is cool. Less radioactive*, zero meltdown chance**,  and less proliferation.

*Only 50-100 years
**Thorium has a higher melting point, which the reaction shouldn't be able to reach.

We aren't going to completely run out of uranium in any reasonable timeframe, but it will become harder and harder to extract so a "peak" situation is possible.  It's already effectively happened in some countries.

Well, uranium production is rising at the moment, and I believe that by 2020 supply should meet demand*. (Information of the World Nuclear thingy.) However, the uranium price is only 10-20% of the maintenance cost of a reactor, so it doesn't matter much.

* There are shortages at the moment.

I also hope more nuclear plants and depleted fuel storage sites are created despite environmental peoples' protesting and NIMBY effect. The short-term 'gain' from not building more nuclear fission plants without having acceptable alternatives is going to make us sorry when something happens. Modern nuclear power plants are extremely safe, but few are being built. :<

Problem in many countries is that either you see replacement of Nuclear by fossil fuels (Ie, coal)* or worse, they don't get replaced. So what you get is that the governements says they'll close the nuclear plants by 20XX (cancelling any serious maintenance of modernisation investements), then when the date comes around, notice that they still need the energy. So they postpone the dates, yet keep doing nothing. In the end you get an overrelience on an network of outdated and undermaintained reactors; all operating beyond their intended lifetime.

*Price for production coal is the only tech that even approaches nuclear.
As for that Virginia link. Nice. Combine it with Gmo algae fields and you get compact carbon to hydrogen systems.

[AlmightyOne]

Thorium does have a lot of potential, my understanding was that it's less popular due to the fact you can't use it to make weapons.

Your evil
It's less popular because they haven't made many thorium only reactors so far, And from where I come from, we have abundant Th but less U.

[Sheb]

The nuclear industry was kick-started by the US Navy that wanted nuclear reactors for their submarines. So we ended up with uranium reactors that are very good at running a submarine, but not the optimal choice for civilian power, and we kinda got stuck in that tech line.

[MetalSlimeHunt]

It's also slightly corrosive and more expensive.

Very corrosive, as far as it's usefulness goes. The corrosive properties of Thorium are the main obstacle in getting the fabled small-scale thorium reactor.

Problem in many countries is that either you see replacement of Nuclear by fossil fuels (Ie, coal)* or worse, they don't get replaced. So what you get is that the governements says they'll close the nuclear plants by 20XX (cancelling any serious maintenance of modernisation investements), then when the date comes around, notice that they still need the energy. So they postpone the dates, yet keep doing nothing. In the end you get an overrelience on an network of outdated and undermaintained reactors; all operating beyond their intended lifetime.

If by "many countries", you mean, "Germany". I know it pisses you off but that's pretty much the only place where that has happened. Won't last either, as the coal market is deeply in the red. Once China starts shunning it in favor of natural gas, that'll be the end of coal.

In any case, closing some of the plants isn't that big of a deal because the plants are mostly very old and beyond retrofitting. The "lifetime gap" caused by the crash in nuclear plant production in the 70's is responsible for this. As such, we're probably better off building fast breeder and thorium reactors anew and closing the old ones down.

Fortunately this is due to happen. Two new plants were chartered in the US just last year.

That said, nuclear does eventually need to be eliminated. With the coming energy crisis that's not an option in the immediate sense, but once the fossil fuels are gone nuclear reduction should be the next goal. While they are objectively very safe, the consequences of the failures that do happen can be extreme.

[Sheb]

Germany is also the only country that gave up on a substantial nuclear capacity. Japan is also starting to import more coal, although it's mostly making its loss of power capacity up with natural gas. And coal is on the rise in Europe, I suggest reading this piece about it.

[10ebbor10]

Problem in many countries is that either you see replacement of Nuclear by fossil fuels (Ie, coal)* or worse, they don't get replaced. So what you get is that the governements says they'll close the nuclear plants by 20XX (cancelling any serious maintenance of modernisation investements), then when the date comes around, notice that they still need the energy. So they postpone the dates, yet keep doing nothing. In the end you get an overrelience on an network of outdated and undermaintained reactors; all operating beyond their intended lifetime.

If by "many countries", you mean, "Germany". I know it pisses you off but that's pretty much the only place where that has happened. Won't last either, as the coal market is deeply in the red. Once China starts shunning it in favor of natural gas, that'll be the end of coal.

Notice the "or". Besides, Germany's not the only country replacing Nuclear by fossil fuel.

Oh, and coal's doing great for the moment actually. Besides, China can't afford to replace such a large part of their energy infrastructure. I don't expect a decrease in coal usage in China for the next 10 years, barring a collapse/decrease in growth of their economy or a massive switch to nuclear.

Germany is also the only country that gave up on a substantial nuclear capacity. Japan is also starting to import more coal, although it's mostly making its loss of power capacity up with natural gas. And coal is on the rise in Europe, I suggest reading this piece about it.

Swiss banned nuclear to, but did the more sensible thing of closing the plants when their lifecycle runs out.

[MetalSlimeHunt]

Oh, and coal's doing great for the moment actually. Besides, China can't afford to replace such a large part of their energy infrastructure. I don't expect a decrease in coal usage in China for the next 10 years, barring a collapse/decrease in growth of their economy or a massive switch to nuclear.

It's not about replacement. China is growing by about one power plant a week right now. I don't think you quite get how majorly the natural gas market is taking over. Whether coal is doing great or not is a matter of perspective. Even if they are making money and growing plants, if they are losing market share and not getting renewed business because of natural gas, which is what is happening now, coal is doomed.

The US has lost almost 10% of it's coal usage in the last ten years and the drop is not stopping. It'll hit China, and soon. When it does, there will be no global viability for coal growth or even coal maintenance, ridiculous policies in Europe or no.

[Descan]

I hope we get something decent working soon. :c
Most renewable energy wrecks the environment (hydro, tidal, wave, biofuel) or has too low energy density (solar) or is way too expensive (geothemal).

Direct solar energy, the traditional solar panels, kind of suck. And for the foreseeable future, will continue to suck.

What I like are the towers in deserts and other lots-of-sun areas, with mirrors point directly at a tower and that heating the steam that drives turbines. Only problem with it is transporting the energy, which if we convert the energy to fuel or some kind of really good battery, should be fixable. :3

[10ebbor10]

Earlier this year the Chinese government released its next five-year plan. Issued before the Japanese nuclear crisis, the plan projected a four-fold growth in nuclear power to 40GW along with 63GW of new hydroelectric capacity, a growth of 22GW in gas-fired generation and 48GW of new wind power to more than double current capacity. Solar capacity is expected to reach 5GW of electricity by 2015. However, in an economy expanding at a rate of at least 8% a year this increased capacity is expected to be dwarfed by an estimated additional 260GW of coal-fired power generation needed to fuel economic growth.

*Text might not be neutral

Forgive me, but I don't see this natural gas overtaking coal anywhere. Primary reason that gas overtakes coal in the US is fracking bringing down costs to historical lows. China is already exploiting shale and the like (largest producer in the world), but it appears to have no real effect on coal growth.

I hope we get something decent working soon. :c
Most renewable energy wrecks the environment (hydro, tidal, wave, biofuel) or has too low energy density (solar) or is way too expensive (geothemal).

Direct solar energy, the traditional solar panels, kind of suck. And for the foreseeable future, will continue to suck.

What I like are the towers in deserts and other lots-of-sun areas, with mirrors point directly at a tower and that heating the steam that drives turbines. Only problem with it is transporting the energy, which if we convert the energy to fuel or some kind of really good battery, should be fixable. :3

Solar thermal has half the Co² output of Solar PV, and 125% the carbon emmision of Nuclear (Second generation).

These ciphers vary wildly from source to source, but these are the most reliable ones.

Oh, and when converting you're looking at least 10% energy loss, up to 50% if you're going for hydrogen production.

[Descan]

Are the carbon emissions from construction or from use?

I'm not sure how carbon could be emitted from use but I'm open to the idea.

I wonder if that carbon could be captured and converted into hydrocarbons instead of being released.

And the efficiency... Does it really matter if there's a loss of energy from gathering to converting to fuel? As long as you don't use more fuel than you create, you should be fine. And since there isn't really any fuel used, just renewable energy from the sun...

Converting it to fuel is not about energy -production-, that's what the thermal tower is for. Conversion is for transportation and ease-of-use considering our current infrastructure.

[Skyrunner]

Electricity isn't for everything, mostly because electricty has a terrible enegy density. You nee to convert it to, say, hydrogen fuel cells to use it in cars.
Efficiency is important because renewable energy isn't free—it costs the environment almost always. Better efficiency also means lower costs and thus more affordable plants.

Also,capturing carbons to convert to hydrocarbon isn't useful at all. If you're going to burn it anyways, why bother using expensive (energy-wise) processes for nothing, compared to getting your daily requirement of hydrocarbons from easier sources? O.o