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chewz

Don't get so excited comrade. Renewable does not mean clean. It is mostly biomass, solar is still tiny % overall.

We are making progress towards clean energy but it is much slower then propaganda numbers.

PS. Congrats to India...

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> Renewable does not mean clean. It is mostly biomass...

Biomass can be as 'clean' as you want it. The term is applicable to anything from a heap of sticks used to cook a pot of cassave to a combined biogas/gasifier plant which emits nothing but CO₂ and H₂O. Don't get scared by CO₂, it is 'clean' as long as it is part of a cycle.

My friend works for Engie/GdF. They are importing coconut shells from Sumatra to France in order to fulfill biomass requirements in their power plants. This is nothing near to clean. It is just another absurd due to eco-regulations.

No, that is a nonsensical construction comparable to what is being done in Stockholm where they import biomass from south America to fuel CHP (combined heat and power i.e. co-generation) systems, this in a country where biomass from forestry is abundant.

The problem here does not lie with the use of biomass but with those who decide to implement it in such a way. Biomass works when there is a reliable fuel source in the form of forestry or agricultural waste, water treatment plant waste, sewage, etc. If you have to import biomass from the other side of the planet just to satisfy some 'green' requirement it is far better to use another power source - this being France I'd say nuclear power should be one of the first options.

And South America to Stockholm distance is covered by some dirty fuel.

Bunker fuel is pretty horrible but shipping by water can be extremely efficient. Seems like you have to do the math to see which effect is more important?

Not necessarily. There are so many cases (even in industrialized countries) of former bog areas turned into farmland by lowering the water level that a biogas plant from corn grown on such ground produces 8 times the CO_2 a lignite plant would have per MW. Just by steady degradation of peat in the ground of the fields.

Also, solar and wind for electricity is a disaster in terms of CO2. People ought to look at the real numbers before thinking that intermittent energies instead of nuclear are going to save us.

What is the basis for your claim? EROEI? I’m curious what those were, so I found these:

Solar EROEI: 9-35

Wind EROEI: 20-50

Nuclear EROEI: 59-70

Which certainly looks great for nuclear (I do actually like nuclear in general), but is it actually important to be the best when it’s high enough to be economic?

You have to compare comparable things: in this case the comparable metric that is actually useful is "be able produce N GW of electricity with a 10% variation over a 60 year timespan". If you count this you'll have to account for the fact that solar and wind are intermittent, which means you'll need batteries or a reliable electricity source, and that's _always_ fossil based (typically gas). You also have to account for the fact that the expected lifespan of batteries and panels is around 30 years, so you have to buy them twice.

In the other side, a nuclear plant does provide a reliable current, has a long lifespan, and turns out to be cheaper. Even the GIEC says so: we won't be able to efficiently reduce our greenhouse gases without nuclear.

Speaking of comparing things correctly, what's supplying the peak power in this nuclear alternative?

Are you accounting for the cost of sufficiently overbuilding nuclear and/or storage? Mostly people seem to fixate on nuclear supplying the legendary "baseload" and leave all the other power as someone else's problem.

And if you add in whatever supplies the power until the nuclear gets built (either solar and wind, which makes nuclear redundant or fossil, which makes it a non solution) then nuclear doesn't really pencil out.

Nuclear today is surprisingly flexible, so it's totally feasible to use it not just for the baseload but for more, like 75% to 90% of the needed power. Hint: there's a country that has shown this as a viable solution.

> And if you add in whatever supplies the power until the nuclear gets built

I don't understand. Are you suggesting building a throwaway source of power until nuclear reactors are built ? That's not how things work. When there really isn't enough countries buy from neighbors. But I agree with your underlying point that building a plant takes a long time; that's why we need to stop being freaked out already and start building them, so we can get rid of all those coal plants.

You're referring to France, the government of which is planning to phase out nuclear in favour of wind and solar and projecting that it will save them billions. So they don't seem particularly convinced by your argument.

They also are one of the largest power exporters in the world, which doesn't really scale up unless we start exporting power to mars.

But regardless of those two separate fatal flaws, I don't think wind/solar advocates would be let off by nuclear advocates if they just handwaved away 10-25% of power and just ignored costs because the extra money would come from hidden subsidies to a nationalised energy sector so I don't see why the reverse isn't fair.

The problem is ecology isn't run by facts anymore, it is run by feelings. The French government will have spent 120 billion dollars to fund intermittent energies. All that money will reduce the nuclear part of the mix to replace it with another source that won't provide more than 10% of the electricity yet will pollute more. Even the Cour des Comptes is complaining that this is absurd and that money should have been spent elsewhere to have actual results (https://www.lemonde.fr/blog/huet/2018/04/19/la-cour-des-comp... in french, didn't find other source).

The French Nuclear eventually needs replaced by something, either more nuclear or renewable, as it's bearing its end of life.

That makes them not too different from any other nation, and they've made the same decision as every other nation, which is that nuclear is too expensive and slow to be considered.

So I agree that other things should be done as well but unless someone has some secret method of building cheap nuclear that they're not sharing then France will spend 120 Billion to replace nuclear with renewables because the alternative would cost even more.

No, they've done the same as other countries, which is follow the so-called ecology-oriented organisations and kill nuclear because that's what the population is asking for, not because it's the best thing to do. Again, if priority number one is to reduce CO2 then renewable won't be enough. If the priority is to find something quick and cheap, then sure, a solar panel is cheap. Except if you need a sustained production for more than 30 years then it's actually more expensive than nuclear. Again, in France it's not replacing fossil, it's replacing nuclear, the second cleanest form of electricity.

If you just want to please the masses and don't care about the environment, then sure, that choice was the good one.

If you’d said that even a few years ago, you’d have been right. Now renewables-plus-batteries have about the same LCOE as nuclear even in France, with plenty of reason to expect both renewable production and storage to become even cheaper. (France already has pumped hydro plants, but I’m not even counting them in the LCOES because I don’t know their capacity or how long they will last, but they’re unlikely to build more because they apparently battery storage is now cheaper).

And I’m saying this as someone who is a fan of nuclear tech and who thinks most of the public fears are disproportionate.

There discussion today that addresses this.

https://news.ycombinator.com/item?id=20317168

"a reliable electricity source, and that's _always_ fossil based"

Hydro, bio fuels?

And don't forget that big nuclear reactor will need maintenance, so you'll need overprovisioning just like wind and solar.

Ps "be able produce N GW of electricity with a 10% variation over a 60 year timespan"

I know you're attempting to compare like with like, but there isn't any inherent reason why this should be the case. Just because the grid has been based on a certain model in the past, doesn't mean we can't use a different model in the future.

Ok so you're actually saying that we should not only approve of those, but also pay to change a working grid ? When there's a perfectly vlaid and working solution ? If it ain't broke, shouldn't we not fix it ?

It is broken, it relies on pumping tonnes of co2 into the atmosphere, so there does clearly need to be a fix. Should the fix be nuclear or something else? That's the question.

Nuclear is expensive, slow to build, but worst of all, it doesn't have the political support. Personally I'm not against nuclear, you get someone to build it then I'll support it, but I don't want to spend time talking other people round to the idea when we could and should be doing something now.

Yep, here's the central point of contention: do we build nuclear that emits little CO2 but needs public support, or intermittent sources that pollutes tens of times more for an equivalent service ? Is the priority feel-goodness about what we're doing, or actually solving the problem ?

Where's your figure for polluting ten times more?

If this is all from (currently) dirty electric grids, then aren't you arguing against cleaning up the grid, because the grid is dirty? That doesn't seem to make much sense.

My comparison is always solar and wind against nuclear. Here's a very good analysis on solar alone: https://solar.lowtechmagazine.com/2015/05/sustainability-off...

In short: in the very good case of an insolation of 1900 kWh/m2/year and panels built in Spain (who has a relatively clean electricity), a reliable system of panels+battery will have emitted 85gCO2eq/kWh over its life. If we correct for the more realistic case of 1000kWh/m2/year (the average in Germany) and panels being built in China with its dirty electricity, the system will have emitted 217gCO2eq/kWh. On the US the insolation is higher, at 1700 kWh/m2/year, so it is going to be around 100gCO2eq/kWh. Here's a map of insulations here: https://upload.wikimedia.org/wikipedia/commons/1/1e/Global_M...

In contrast, nuclear is at 12 gCO2eq/kWh (https://en.m.wikipedia.org/wiki/Life-cycle_greenhouse-gas_em...). The disaster that solar is should be clear for everyone.

Your figures are measuring different things.

The lowtechmag link is for an off grid solar and battery combo. Off grid nuclear isn't a thing as far as I'm aware.

Whereas the wikipedia link includes comparisons on all generating methods, which I would guess means they're an apples to apples comparison, so that means onshore wind in better than nuclear, offshore wind is as good as, and solar is only 5 times worse.

And to restate the point in my last comment, the lowtechmag figures at least are based on a dirty grid, as the grid cleans up and the solar figures improve. Lets assume you get your way and we build out nuclear. Solar's figures will improve and eventually surpass those of nuclear. In that situation would you support moving over to solar?

Your own link which claims 12 gCO2e/kWh for nuclear also claims 48 gCO2e/kWh for utility scale solar.

The same reference also put coal at 820 gCO2e/kWh.

Given the two options are:

1) nuclear power in 5-10 years when the reactor is finished, saving nothing for the intervening period and (820-12) = 808 gCO2e/kWh for the next 50 years

Or 2) solar power now, saving (820-48) = 772 gCO2e/kWh for the next 30 years, while totally not preventing you from also building nuclear reactors and simultaneously lowering the carbon footprint of any new power plants whose construction involves a lot of electricity…

…I think you’re making the good the enemy of the perfect.

One is a 98.5% reduction, the other is a “mere” 94.14% reduction, where in both cases we need to also roughly halve non-electric CO2 emissions.

Source please.

https://en.m.wikipedia.org/wiki/Life-cycle_greenhouse-gas_em...

Solar is listed at 4x more and wind seems to be on par with nuclear. Both solar and wind are far better than the hydrocarbon alternatives.

I used to be very pro nuclear but I think nuclear has a lot of hidden costs - very long ramp up time, long and expensive cleanups.

Doesn't account for the technology needed to make solar and wind reliable, you won't get the same numbers.

See some numbers in https://solar.lowtechmagazine.com/2015/05/sustainability-off...

> Both solar and wind are far better than the hydrocarbon alternatives.

Agreed, of course. I'm only mentioning nuclear because people tend to think that merely replacing fossil with pv/wind is good enough. Not only is it not enough, it's also more expensive and barely getting us to the right track. Nuclear isn't perfect of course, but all things considered it's still better.

Solar and wind are reliable, just not necessarily consistent. Aging coal plants are unreliable (they can and do fail without warning), compared to solar and wind, which run reliably when the sun is shining or wind is blowing, both of which can be predicted quite accurately for a few days.

That's not the same meaning of reliable. What is usually meant is "can I trust this source to give me this amount of power at this time", or can I rely on it being available: fossil can, intermittent (by definition) can't. You need to look at the overall electricity generating system, not just the individual sources hoping they will seamlessly integrate in the grid with little changes.

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