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Why Nuclear Must Be Part Of The Energy Solution (2018)

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Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#151

Post by corty »

lorenzhs wrote: post #135
hntrader wrote: post #59

Earlier quoted context omitted.

"four times as expensive as wind" This isn't a valid comparison, since wind isn't capable of base load supply. You would need to factor in storage costs to make the comparison valid.

"Base load" doesn't really exist any more. Yes, there's a minimum below which demand almost never dips, but the implication of base load is that this should be produced by the type of power plants that provide a continuous supply, like nuclear or coal. But these are extremely inflexible and can't react quickly to changes in demand or supply by other means. As the share of renewables grows, the position nuclear is in…

Nuclear isn't as inflexible as you think. A usual change rate in power output is around 10%/min, so you can go from half to full in 5 minutes. Far away from days or weeks. Here is a nice comparison: https://de.m.wikipedia.org/wiki/Lastfolgebetrieb

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#152

Post by konjin »

melling wrote: post #145
pumpkinpal wrote: post #119

Earlier quoted context omitted.

We've also spent 30+ years trying to build nuclear plants on time and on budget and we've been unable to do that.

Even with that, 20% of US electricity is still from nuclear. We managed to build these before the industry became expensive. Now Germany and the United States are rushing to close the operating plants. I’m not sure why we can’t figure out how to build a standard design and replicate it

Because we can't build anything larger than an office building on time and on budget.

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#153

Post by kdtsh »

corty wrote: post #151
lorenzhs wrote: post #135

Earlier quoted context omitted.

"Base load" doesn't really exist any more. Yes, there's a minimum below which demand almost never dips, but the implication of base load is that this should be produced by the type of power plants that provide a continuous supply, like nuclear or coal. But these are extremely inflexible and can't react quickly to changes in demand or supply by other means. As the share of renewables grows, the position nuclear is in…

Nuclear isn't as inflexible as you think. A usual change rate in power output is around 10%/min, so you can go from half to full in 5 minutes. Far away from days or weeks. Here is a nice comparison: https://de.m.wikipedia.org/wiki/Lastfolgebetrieb

On a synchronous grid? Unless the capacity of the nuclear plant is tiny (which means the economy of scale is lost - who is building a nuclear plant in the area of 10s of MW?), you instantly have voltage instability if you lose supply, and yes, bringing the network back to synchronicity can take days or weeks. This is the same issue we have with coal, which is part of the reason we are trying to diversify the grid (large synchronous machines are not all bad because they do maintain inertia in the network, which means it is easier to maintain voltage stability, but machines like synchronous condensers can provide this without needing to pin our energy requirements on it).

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#154

Post by gmueckl »

lorenzhs wrote: post #141
gmueckl wrote: post #130

Earlier quoted context omitted.

Right now, the southern half of Germany has clear skies and thus a bright, sunny day approaching noon. These are optimal conditions for solar energy. This is why renewables get to approx. 40% of the energy mix right now. Let's have another look at those numbers around sunset (approx. 6 hours from now) and see where that goes.

"Utilizing 28.36% of installed capacity" is what the linked map says about solar right now. I just rewound the slider to 8pm yesterday and it says "35% renewable".

I am not sure how much of these 28% are due to the distribution of solar panels in Germany and how much is due to seasonal effects. Solar irradiation varies a lot over the year. I vaguely remember that it goes down to about 300W/m^2 at noon in winter and peaks at around 1kW/m^2 at noon in summer, but I don't have time to verify that right now. The exact numbers vary by location, of course.

But I can confirm that the sun is shining because it's shining directly on my roof and satellite images show a clear sky for anything south of Frankfurt.

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#155

Post by amai »

"a Pulitzer Prize-winning author argues that nuclear is safer than most energy sources"

Since when are Pulitzer prize winners experts on nuclear energy?

A sentence like this is shows he has absolutely no clue what he is talking about:

"Nuclear waste disposal, although a continuing political problem in the U.S., is not any longer a technological problem."

see https://www.youtube.com/watch?v=ZwY2E0hjGuU

"A final complaint against nuclear power is that it costs too much. Whether or not nuclear power costs too much will ultimately be a matter for markets to decide, but there is no question that a full accounting of the external costs of different energy systems would find nuclear cheaper than coal or natural gas. "

Ok, see here https://www.carbonbrief.org/wind-and-solar-are-30-50-cheaper... Nuclear is already the most expensive solution to produce electricity.

Also we don't need artificial nuclear energy here on Earth. There is plenty of nuclear energy available for free from the sun.

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#156

Post by kuschku »

Rokid wrote: post #12
legulere wrote: post #6

> Whether or not nuclear power costs too much will ultimately be a matter for markets to decide It’s not a market decision, but a government decision, as nuclear power has always been built with state guarantees and/or subsidies. This article also again equates safety with lack of deaths. That’s like saying a neighborhood is safe, because in the robberies there only a few people die. Chernobyl and Fukushima had drama…

Chernobyl and Fukushima are not the best arguments against nuclear imo. Chernobyl was underbudgetted in terms of safety. For instance no protective dome was places around the reactor housing as done in other countries. Add that to a suboptimal design to start with and sheer bad luck... Fukushima on the other hand is a better comparison. But on larger scales, such as Europe or the US, surely it must be possible to pla…

> surely it must be possible to place the plants in areas that are not subject to such natural disasters that would threaten the safety of the reactors?

Reactors need lots of water for cooling, so they're regularly placed at rivers. Rivers flood during melting season and storms. Storms also interrupt the grid occasionally. Due to climate change, these events are getting more common.

As a result, anywhere you can place reactors, you'll have to deal with situations where you have no grid connection, no backup power, no generators, and flooding, at unexpected times.

A nuclear reactor needs always, 24/7, forever power due to cooling. This isn't really compatible.

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#157

Post by ArkanExplorer »

When you consider any public infrastructure - roads, telecommunications, electricity grids - the bottleneck is always how much can be supplied during peak periods.

When we add capacity, its always to address the peak demand.

The solution is to get smarter about shifting demand, particularly as we build out a massive fleet of EVs.

Here's an example of hourly electricity use in Florida: https://energymag.files.wordpress.com/2014/02/daily-demand-f...

We need appliances that can take into account grid pricing, and any local power supply that the owner has (solar, EV battery), and adjust accordingly. eg. heating or cooling a house an hour earlier than when the owner would typically manually request it.

Secondly for EVs that can charge offpeak at night (eg. at 9pm, not simply when the owner gets home at 6pm and plugs it in - contributing to peak demand) and then upload some power back into the grid in the morning, and then during the day again if necessary.

Its going to be hard to integrate this into appliances, but power upload and smart charging/discharging should be mandated for new EVs.

While we're at it we should also begin charging for time of use for roads - to reduce congestion, and replace the revenue from gas taxes. This UI and charging mechanism could be built into the infotainment system.

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#158

Post by orwin »

cygx wrote: post #109
realusername wrote: post #41

Earlier quoted context omitted.

That's where we are at right now, just stating the energy facts are considered political... There's no realistic scenario at the moment where renewables can be used alone to build a grid for a full country unless you are betting on future tech which doesn't (and might never) exist.

Because it's overstating the facts ("no other source", "seen only in Star Trek", "as much understanding of energy as flat earthers do of geography", "ridiculous"), contradicting any study on the topic I've seen (which, to be fair, might have been a biased sample). This was my take-away when I looked into it a couple of years ago: Going 60% renewable is not much of a problem. 80% needs investment into infrastructure,…

We don't need 100% renewable, we need 350% renewable. Electricity is at best 25% of our energy usage. 20% of the energy i'm consumming everyday come from nuclear and i'm living in France, where 80% of our power grid is nuclear.

And we need the grid investment in copper that comme with it if we want a distributed grid. And a secondary grid to serve hospital and emergency buildings.

Oh, and we need Veolia's solar panel recycling plant: its economical, recylce 91 to 95% of the product (granted, the less important part) and it only cost 8 time the raw materials, making it the most efficient solar panel recycling plant (and the only one in the world of its size). It also cost 5 time the energy of raw material extraction and transformation, and weirdly, this is never taken into account when the cost of solar PV is on the table, as if everyone think we can just put lead and cadmium in a landfill. Oh yeah, that's right, we can and we did, nice job us.

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#159

Post by yokaze »

realusername wrote: post #48
yokaze wrote: post #44

Earlier quoted context omitted.

> No other fuel has the energy density of nuclear Irrelevant, unless you want to have a mobile power generator. > no other source has the capability to run 24/7/365. First, not true: Geothermal and hydro both can generate power 24/7/365. Yes, that is location dependent, but you set yourself up there with using absolutes ( https://en.wikipedia.org/wiki/Electricity_sector_in_Iceland .) Second, we do not need a single s…

I strongly doubt there's that many places where you can build some hydro plants which haven't been used yet. At least there's approximately none in Europe. That's fine as a philosophical thought but in reality, all the hydro capacity is already used.

I merely wanted to disprove the hypothesis "no other source has the capability to run 24/7/365" by example.

I am not making an argument that we should go all-in on hydro power instead. Quite the contrary, I am arguing against a single source of power, but a diversification.

Re: Why Nuclear Must Be Part Of The Energy Solution (2018)

#160

Post by ketzu »

amarant wrote: post #116
ketzu wrote: post #65

Earlier quoted context omitted.

One of the points of the toplevel comment is exactly > This article also again equates safety with lack of deaths. So adding a statistic that only focuses on that seems not helpful to me. Are there some available that give a broader analysis (that might not be as catchy for social media)?

What other metric would you use though? It seems to me the top-level comment is arguing "I think nuclear is scary so therefore statistical risk analysis is invalid" I disagree.

Impact on eco systems and economy, injuries, and maybe other effects that are not easily compressed into a single number. I don't disagree that Deaths/GWh is one of the most important statistics on the safety of energy production. But while we often quantify safety of roads/vehicles by deaths/billion length units driven, one assumption is it is highly correlated to other safety indicators such as injuries. Coal will probably be even worse considering these statistics and nuclear will probably still fare well.

One example I am aware of: Germany still monitors contamination of mushrooms and other wildlife in bavarian soil [1]

[1] http://doris.bfs.de/jspui/bitstream/urn:nbn:de:0221-20191007...

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