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Nuclear power: Are we too anxious about the risks of radiation?

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Re: Nuclear power: Are we too anxious about the risks of radiation?

#271

Post by reitzensteinm »

VBprogrammer wrote: post #257
reitzensteinm wrote: post #234

Earlier quoted context omitted.

You can use batteries more than once! If you cycle them once per day for ten years to store solar power until night, your numbers given mean they add $30-100 per MWh to the cost of that stored power (but not daytime use). Not cheap, but in no way a "fantasy". Certainly not in a world with sane carbon pricing.

So the cost of storage would exceed the cost of generating the same power via a CCGT plant?

I just took parent's numbers at face value to show how they were misinterpreting them.

I haven't seen much in the way of true apples to apples comparisons. Most solar plants with storage don't have much storage. For instance I saw a link this week on HN for $30 + $15/MWh for solar + storage, but the storage was only one hour of the nameplate capacity.

Based on the falling prices of batteries, I don't think it will be long before solar + storage providing power evenly over 24h (an unrealistic worst case) becomes economical.

At a 30% capacity factor, assuming the batteries are charging for 8 hours and draining for 16, that plant would need 5x as much storage for a cost of $30 + $75/MWh.

More realistically you'd only need 3-4x as much storage as you get small amounts of sunlight later and earlier in the day, and demand curves are not flat. Halve the price of batteries, which already happened in the 2010s, and that's looking economical even with a zero price on carbon.

But most countries are pretty far from saturating solar potential, so you can still build solar without storage for a while. Once you need the battery backing, it's probably going to be cheap enough.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#272

Post by adrianN »

Manfredo_1 wrote: post #266
choeger wrote: post #236

Earlier quoted context omitted.

You are mixing up the price of capacity vs. the price of generating the electric energy. A battery for 100/kwh can be used several 100 to 1000s of cycles.

> A battery for 100/kwh can be used several 100 to 1000s of cycles. You're making the same error as reitzensteinm. The fact that you can charge and discharge a 1 KWh battery a thousand times doesn't make it a 1 MWh battery. If the United States wants to use 80% renewables we need 12 hours of energy storage, which works out to 6 TWh. Even at a very generous cost estimate of $100/KWh, this works out to 600 billion doll…

You can avoid a lot of storage requirements by making your grid smarter and electrifying transportation and heating. 60% renewables are possible with hardly any storage at all, certainly less than 12 hours. Shifting demand is always cheaper than storage. Once you've electrified transportation, you have hundreds of millions of car batteries that can help out with demand spikes. That distributes the high upfront cost of battery storage somewhat. Car batteries that are no longer good for transportation can than be repurposed for grid storage, hopefully much cheaper than buying new batteries.

To get to 100% renewables you most likely need chemical storage as hydrogen or methane.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#273

Post by emteycz »

7952 wrote: post #232
ComputerGuru wrote: post #171

Earlier quoted context omitted.

Are you really suggesting those have zero externalities not priced in?

The externalities are orders of magnitude less complex to deal with.

This right here is a prime example of Dunning-Kruger effect. You're completely forgetting the large scale effects on nature, for example, which nuclear does not have.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#274

Post by reitzensteinm »

Manfredo_1 wrote: post #261
reitzensteinm wrote: post #234

Earlier quoted context omitted.

You can use batteries more than once! If you cycle them once per day for ten years to store solar power until night, your numbers given mean they add $30-100 per MWh to the cost of that stored power (but not daytime use). Not cheap, but in no way a "fantasy". Certainly not in a world with sane carbon pricing.

No, that's not this works. Batteries currently cost ~$150 to $250 per KWh. As in, if you want to store one kilowatt hour, you need to spend $150 to $250 dollars on batteries. If you want to store one megawatt hour, then that's $150,000 to $250,000 worth of batteries. Yes, you can cycle this battery multiple times. I'm not sure how you think that this somehow makes storage cheaper. The fact that you can charge a 1 KWh…

Parent compared the price of one MWh of power from a natural gas plant with the capital cost of building batteries that can store one MWh. This is a type error.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#275

Post by reincarnate0x14 »

arrosenberg wrote: post #191
pfdietz wrote: post #50

Earlier quoted context omitted.

> So far the largest solar plant in the world is about 1500MW in China. That’s still only a fraction of the largest nuclear facilities in the world. Why is this a problem? If solar plants can be cheap without being big, that's a feature, not a bug.

A 1.5GW solar plant is going to cover a massive amount of land. For comparison sake, the decommissioned San Onofre Nuclear Plant had roughly 2.7 GW of generation capacity, and the official website estimates it would take roughly 18 square miles of solar panels to replace that capacity. https://www.songscommunity.com/about/virtual-tour

Not sure how they arrived that that number as the effective capacity factor of solar is in the 25-28% range in the best of circumstances, so my napkin math of realistic PV density from real projects like Desert Sunlight (the 550 MW plant in the Mojave that covers about 6.5 sq miles) puts that at closer to 101 square miles of equivalent capacity at (.90 capacity factore versus .28, roughly 88 MW per sq mile on a totally flat desert), and that's not counting whatever storage is being used to offset all the non-generating hours.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#276

Post by Ovah »

bad_user wrote: post #206
Ovah wrote: post #27

Earlier quoted context omitted.

Correlation is indeed not causation. However all four statements hold true for correlation. And at least alcohol can cause cancer. - Bad diet: for example red meat increases risk of colorectal cancer. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4698595/ - physical activity reduces the risk of many cancers. https://www.cancer.gov/about-cancer/causes-prevention/risk/o... - overweight people have a higher risk of cance…

> - physical activity reduces the risk of many cancers Logical fallacy.

I'm interested in what way this could be a logical fallacy. Would you care to expand?

Re: Nuclear power: Are we too anxious about the risks of radiation?

#277

Post by Cthulhu_ »

BurningFrog wrote: post #145
ComputerGuru wrote: post #125

Earlier quoted context omitted.

Nuclear is only so relatively expensive because it’s the only fuel source that’s forced to pay up for all the externalities up front (and I’m not saying that is a bad thing to require). A nuclear plant can’t be built if the money to make it safe (as per some specification), insure against all health complications while it’s in operation, decommission it, clean up the site, securely dump all spent fuel, and return the…

> securely dump all spent fuel Reminder that Coal and oil energy gets to dump their spent fuel in the atmosphere, and thereby our lungs! The uneven treatment of different energy sources really is fantastic!

And that burnt coal leaves a toxic waste product that also needs to be taken care of safely.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#278

Post by mantap »

roenxi wrote: post #248
rgbrenner wrote: post #169

Earlier quoted context omitted.

Your post conveniently ignores solar/wind + batteries, which is even cheaper than coal.

Those are held to a much lower standard. I've seen people on HN seriously argue that we need to isolate nuclear waste from the biosphere for multiple generations, including contingencies for the collapse of English as a comprehensible language. What is the plan to isolate the poisonous meals in a solar panel for multiple generations? There isn't one. It just goes in landfill, I expect with relatively little concern f…

Radioactive material is treated differently because it is dangerous at a distance. You don't need to eat it or even touch it. Simply standing close enough to it is enough to be harmful. It's just not comparable to anything in a solar panel.

After decommissioning a solar farm, at worst the soil might not be suitable for farming but nobody would complain about building a house there. For the same to be true of a nuclear plant a very expensive decommissioning process must be completed.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#279

Post by noobermin »

ComputerGuru wrote: post #125
Lazare wrote: post #53

Do we stress about the risks nuclear power far out of proportion to how safe it is? Yes. Even accounting for the worst accidents, it kills a very low number of people per TWh. Do we ignore the risks of fossil fuels far out of proportion to how dangerous they are? Also yes. They kill an absurdly high number of people per TWh; by most estimates coal is several hundred times more dangerous than nuclear. Does that mean n…

Nuclear is only so relatively expensive because it’s the only fuel source that’s forced to pay up for all the externalities up front (and I’m not saying that is a bad thing to require). A nuclear plant can’t be built if the money to make it safe (as per some specification), insure against all health complications while it’s in operation, decommission it, clean up the site, securely dump all spent fuel, and return the…

I'm right now ambivalent on nuclear in its current form, but you're darn right it's not a fair fight (some would say free market). Petrol is subsidized up the wazoo in addition to people ignoring the externalities of climate change and pollution.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#280

Post by DoctorOetker »

nobodyandproud wrote: post #237
DoctorOetker wrote: post #209

Earlier quoted context omitted.

As long as the mining activity was by informed consent, i.e. no slavery explicit nor implicit, any life and healthcost of mining, recycling and disposal is incurred with informed consent...

The effects of mining and disposal don’t disappear after one generation, and solar and wind is not a solution that works for all climates and regions. The multi-generational ethical problems you’ve constructed apply to oil; gas; solar; windmills; nuclear. To put it another way: There is no free lunch, but some sources like gas and oil must be reduced. Of that there is no doubt. The unethical choice is to outright dis…

sorting isotopes takes a lot more energy than sorting chemicals
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