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The New Atomic Age We Need

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Re: The New Atomic Age We Need

#141

Post by madaxe_again »

ScottBurson wrote: post #124

I'm in the middle of reading a great book on geoengineering, Oliver Morton's The Planet Remade . Engagingly written and comprehensive; I recommend it highly. From the introduction: If the world had the capacity to deliver one of the largest nuclear power plants ever built once a week, week in and week out, it would take 20 years to replace the current stock of coal-fired plants (at present, the world builds about thr…

I'd actually say that delivering one large power station per week is a fairly unambitious goal, and that if the will were there, globally, dozens of plants could be onlined per day.

That said, uranium is a finite resource, and even if we built all of these plants we'd be looking at peak uranium in the not too distant future.

Therefore, either we go for thorium, which is looking increasingly promising, or as you say we consider geoengineering.

Even if we stop burning fossil fuels, another problem remains, which is thermodynamics - the waste heat from our energy use has to go somewhere, and right now the only place it can go is into the earth, or into space - and we're not doing much of either, other than inadvertently. If we keep up current rates of energy growth, we'll cook ourselves before too long regardless of what source the power comes from.

Re: The New Atomic Age We Need

#142

Post by T-A »

CamperBob2 wrote: post #125
ScottBurson wrote: post #124

I'm in the middle of reading a great book on geoengineering, Oliver Morton's The Planet Remade . Engagingly written and comprehensive; I recommend it highly. From the introduction: If the world had the capacity to deliver one of the largest nuclear power plants ever built once a week, week in and week out, it would take 20 years to replace the current stock of coal-fired plants (at present, the world builds about thr…

If the world had the capacity to deliver one of the largest nuclear power plants ever built once a week, week in and week out, it would take 20 years to replace the current stock of coal-fired plants (at present, the world builds about three or four nuclear power plants a year, and retires old ones almost as quickly). That's extremely hard to believe. Does he show the math?

Let's se... According to [1], world electric power generation from coal in 2014 was 8726 TWh. The largest nuclear power plant in the US, Palo Verde, delivers on average 3.3 GW [2], or 365243.3 = 28908 GWh/year. So you would need 8726/28.9 = 302 nuclear power plants of that size to replace all coal plants. At a rate of one per week, it would take less than six years.

But! Palo Verde has three reactors. If you assume that he really meant "reactor" rather than "plant", and went with 1 GW as its output, it would take a little more than 19 years.

[1] http://www.tsp-data-portal.org/Breakdown-of-Electricity-Gene...

[2] https://en.wikipedia.org/wiki/Palo_Verde_Nuclear_Generating_...

Re: The New Atomic Age We Need

#143

Post by Pietertje »

CamperBob2 wrote: post #125
ScottBurson wrote: post #124

I'm in the middle of reading a great book on geoengineering, Oliver Morton's The Planet Remade . Engagingly written and comprehensive; I recommend it highly. From the introduction: If the world had the capacity to deliver one of the largest nuclear power plants ever built once a week, week in and week out, it would take 20 years to replace the current stock of coal-fired plants (at present, the world builds about thr…

If the world had the capacity to deliver one of the largest nuclear power plants ever built once a week, week in and week out, it would take 20 years to replace the current stock of coal-fired plants (at present, the world builds about three or four nuclear power plants a year, and retires old ones almost as quickly). That's extremely hard to believe. Does he show the math?

The math is rather easy, it is however questionable what you define as one of the largest nuclear power plants. Most power plants have multiple units, if you take the power per unit you more or less end up with 20 years.

Capacity of large nuclear power plant unit: ~1 GWe [1] Total world electricity consumption is 20,900 TWh/year [2], of which 40% is generated by coal power plants. A total power of ~1000 GWe, so you'll need 1000 nuclear power plants to replace all coal-fired plants by nuclear power plants.

[1] https://en.wikipedia.org/wiki/List_of_nuclear_power_stations [2] https://en.wikipedia.org/wiki/Electric_energy_consumption

Re: The New Atomic Age We Need

#144

Post by ScottBurson »

madaxe_again wrote: post #141
ScottBurson wrote: post #124

I'm in the middle of reading a great book on geoengineering, Oliver Morton's The Planet Remade . Engagingly written and comprehensive; I recommend it highly. From the introduction: If the world had the capacity to deliver one of the largest nuclear power plants ever built once a week, week in and week out, it would take 20 years to replace the current stock of coal-fired plants (at present, the world builds about thr…

I'd actually say that delivering one large power station per week is a fairly unambitious goal, and that if the will were there, globally, dozens of plants could be onlined per day . That said, uranium is a finite resource, and even if we built all of these plants we'd be looking at peak uranium in the not too distant future. Therefore, either we go for thorium, which is looking increasingly promising, or as you say…

Even if we stop burning fossil fuels, another problem remains, which is thermodynamics - the waste heat from our energy use has to go somewhere, and right now the only place it can go is into the earth, or into space - and we're not doing much of either, other than inadvertently. If we keep up current rates of energy growth, we'll cook ourselves before too long regardless of what source the power comes from.

Not remotely true. The amount of solar energy that falls on the Earth and is not immediately reflected is 120PW (petaWatts), or 120,000TW. The total amount of energy being used by humans is about 15TW. So the heat we're generating changes the Earth's energy balance by a little more than .01%. (Numbers from Morton's book.) Essentially all of that 120PW is also being radiated away as infrared from the night side of the Earth.

Re: The New Atomic Age We Need

#145

Post by Retric »

pilom wrote: post #104
Retric wrote: post #60

Earlier quoted context omitted.

BS, solar is not great in the UK, but your comparing electric generation at 2009 efficiency levels with powering cars, heating using resistance heating etc. (Heat pumps break 100% nominal efficiency by extracting heat from outside air.) It's also perfectly reasonable for the UK to continue to import significant amounts of energy in one form or another and or increase efficiency levels. EX: We can manufacture 40+% eff…

Later on on page 44 he changes the assumptions based on 50% efficient farms growing plant matter for biomass. Even if you had 50% efficient panels and you covered 200m^2 per person with them (there are only about 900 m^2 per person that are not covered with farm land or roads), you'd only get about 32KW/person/day which is less than what the energy used for transportation alone (40kw/person/day).

200m^2 at 500w/m2 * 8 hours a day x 20% efficency = 160kwh. Which you could get in the UK using mid range solar cells right now. 50% would get you 400kwh.

Further you can mix solar and wind farms as the wind farm does not take up much space.

Also, he uses mixed units when not realistic. A Tesila roadster for example gets 390 km from a 52kwh battery pack. Doing a direct petroleum has X energy so you need that much electricity is dum as cars have terrable efficency.

But, most importantly the UK already imports a lot of food and energy, making this a really silly comparison. Solar cells in Africa can more cheaply provide energy so that's a better place to put them.

Re: The New Atomic Age We Need

#146

Post by merpnderp »

chefkoch wrote: post #132
merpnderp wrote: post #98

Earlier quoted context omitted.

This times one hundred. Nuclear in the West is far more expensive than places like China and Vietnam not because western plants are better or safer but because they face incredible legal and regulatory hurdles designed to appease people's irrational fears.

Shure, China is atm mostly using a more than 30 year old design bought from france and everyone knows safety is not their primary concern. https://en.wikipedia.org/wiki/Nuclear_power_in_China#Reactor...

Yes, that French design that has such a horrible safety record in France. Oh wait, it has an excellent record and France is still exporting power from those designs. And I don't think everyone knows that safety is not their primary concern. What other country shoots CEO's in the head when they put citizens at risk with poisoned products or environmental disasters?

Re: The New Atomic Age We Need

#147

Post by CamperBob2 »

T-A wrote: post #142
CamperBob2 wrote: post #125

Earlier quoted context omitted.

If the world had the capacity to deliver one of the largest nuclear power plants ever built once a week, week in and week out, it would take 20 years to replace the current stock of coal-fired plants (at present, the world builds about three or four nuclear power plants a year, and retires old ones almost as quickly). That's extremely hard to believe. Does he show the math?

Let's se... According to [1], world electric power generation from coal in 2014 was 8726 TWh. The largest nuclear power plant in the US, Palo Verde, delivers on average 3.3 GW [2], or 365 24 3.3 = 28908 GWh/year. So you would need 8726/28.9 = 302 nuclear power plants of that size to replace all coal plants. At a rate of one per week, it would take less than six years. But! Palo Verde has three reactors. If you assume…

Interesting, thanks. What confused me is that we've all seen pie charts like the one at http://www.tsp-data-portal.org/Breakdown-of-Electricity-Gene... that show the relative "market share" of various energy sources with nuclear playing a significant but not dominant role. In this case it's 11% nuclear, 39% coal. It's easy but incorrect to assume that the number of plants of each type is proportional.

Wikipedia says there are about 50,000 coal plants online, as ScottBurson notes, but I know there aren't 50000*11/39 = 14000 nuclear plants in the world. Googling "number of nuclear power plants" returns an answer of 438 "reactors." Obviously the number of plants is somewhat smaller, and we don't know if the statistic includes military reactors on subs and carriers. Call it 400.

So what I've missed appears to be the fact that a typical nuclear plant must generate 14000/400 = 35x as much power as a typical coal plant. The largest plants of both types are in the gigawatt class, so most of those 50000 coal plants must be significantly smaller.

So, at some point, it must have been decided that most nuclear plants needed to be as powerful as the largest coal plants. Absent a change in policy, that clearly denies the nuclear industry the benefits of economies of scale... unless those economies are realized on a per-plant basis. (E.g., if it doesn't cost much more to build a 1 GW nuke plant than a 100 MW one, you might as well build the former.)

Re: The New Atomic Age We Need

#148

Post by mightybyte »

tokipin wrote: post #128
thebmax wrote: post #108

Earlier quoted context omitted.

These cost comparisons don't take into account reliability. Power is almost useless if it's not reliable. A large part of your monthly bill goes towards reliablility and transport of power, not just the power itself. A 100% wind or solar grid would require an equal amount of backup gas or coal power in order to provide reliability which essentially doubles these cost estimates. Even now most wind and solar is conside…

the obvious solution is batteries, which improve all sources of power generation including traditional ones by serving as support during peak times. in principle you only need stored per house during night time, which may be a much lower bar than it sounds. if the utilities serve a role later it may just be them acting as high-volume energy storage facilities, but even that might not really be necessary if individual…

Batteries aren't the only solution here. Any kind of efficient energy storage will work. For example LightSail Energy has been working on compressed air storage for several years now.

Re: The New Atomic Age We Need

#149

Post by Pietertje »

Does somebody know if nuclear power will actually be an improvement for the environment (only considering temperature here)? Essentially you just release heat which is stored as mass.

A quick calculation shows that if you only consider heating up our atmosphere and assume an entire switch of all our energy consumption to nuclear energy you end up with a temperature rise of 0.1 deg C per year. I know it is a worst-case scenario - energy will be stored in land/water as well, dissipation etc. - but still.

Compared to fossil fuels, the plus side is you do not produce any greenhouse gases. However, I'm unsure which contributes more to global warming, could well be the former is negligible. Would love to hear an expert on this.

Re: The New Atomic Age We Need

#150

Post by lyschoening »

thebmax wrote: post #108
T-A wrote: post #8

> We already know that today’s energy sources cannot sustain a future we want to live in. Is this really true? In Lazard's 2014 comparison of total cost per MWh, both wind and solar beat coal and nuclear [1]. Costs have fallen so much that it's becoming hard to justify continued subsidies [2]. [1] http://energyinnovation.org/2015/02/07/levelized-cost-of-ene... [2] http://www.treehugger.com/renewable-energy/us-energy-…

These cost comparisons don't take into account reliability. Power is almost useless if it's not reliable. A large part of your monthly bill goes towards reliablility and transport of power, not just the power itself. A 100% wind or solar grid would require an equal amount of backup gas or coal power in order to provide reliability which essentially doubles these cost estimates. Even now most wind and solar is conside…

A large enough HVDC grid would almost totally eliminate the need for backup power. There's always wind or sun somewhere and HVDC transmission losses are <5% per 1,000mi. It's possible to build a grid where pumped and battery storage alone can smoothen out any fluctuations.
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