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China's quiet energy revolution: the switch from nuclear to renewable energy

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Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#71

Post by loeg »

com2kid wrote: post #61
loeg wrote: post #52

Earlier quoted context omitted.

> I know people in Seattle who run their entire house off solar for 6-8 months on the year (important now that AC is increasingly needed around here...) and who don't fully deplete their battery bank until January. So what? They've invested a large amount of capital in order to avoid low $0.13/kWh residential electricity rates that come from more or less entirely carbon-free sources (mostly hydro, some nuclear/wind).…

> So what? They've invested a large amount of capital in order to avoid low $0.13/kWh residential electricity rates that come from more or less entirely carbon-free sources As per PSE (the power company for the Seattle Metro but outside of Seattle itself), only 23% of the energy sent to surrounding areas outside of Seattle city proper is from hydro. FWIW Nuclear is less than 1%. 46% is fossil fuels, natural gas and c…

We're talking about Seattle residents. We get power from Seattle City Light, not PSE.

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#72

Post by JumpCrisscross »

pfdietz wrote: post #70
JumpCrisscross wrote: post #63

Earlier quoted context omitted.

> It's e-fuels like hydrogen. Yes, the round trip efficiency sucks, but for year-long storage the cost of inefficiency is very low This is still pie in the sky technology. Particularly given the frequencies, magnitudes and durations we’re considering. At that point SMRs become topical. > we can back up the grid with these turbines for a very small fraction of the cost of building nuclear power plants to power the gri…

> This is still pie in the sky technology. 4% of the hydrogen production in China is by electrolysis now. Electrolysers there are below $300/kW. You object to this because it's not available, then you point to SMRs, which don't exist now except on slides. And given NuScale's recent disappointments one should not expect the rosy promises of their (or other) SMRs to come true or find much of a market. > Absolutely. If…

> You object to this because it's not available, then you point to SMRs, which don't exist now except on slides

Right. Long-term large scale hydrogen manufacturing and storage (presumably as ammonia) is not a thing, not to the tune of several percentage points of primary generation. This is speculative, like SMRs.

> Hydrogen + batteries are nicely complementary and enable renewables to undercut new construction nuclear even for supplying baseload power

The math doesn’t work with current technology. Not at that scale. (The lithium alone would be orders of magnitude more than what is forecast to be needed for EVs.)

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#73

Post by h0l0cube »

dyauspitr wrote: post #69
h0l0cube wrote: post #50

Earlier quoted context omitted.

Nuclear is great as a baseload, but as wind and solar reach overcapacity, peakers will be more useful to react to changes in weather. But by then, energy storage will be economical and scalable enough to obviate gas and coal for this purpose. Renewable takeover is a foregone conclusion at this point. That said, from a conservation point of view, nuclear is something I’m in favor of

It’s what I was trying to get across. Use nuclear where you would use a peaked plant and then direct the nuclear entry into storage when renewables are active.

My point is that nuclear isn’t suitable for peaking, and given the lead times and capex for building new plants, and the rapidly declining price of storage, it makes them an undesirable financial investment especially when you consider that renewable overcapacity will shift the need from baseload to backup. The better bet is storage, with gas peakers tiding us over for the next 1-2 decades before they are obsolete too

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#74

Post by KevinMS »

TeeMassive wrote: post #3

I've always found these articles about China adopting green policies and shifting its industries towards green energy sources to be suspicious. If they were true then why are China's emission ever increasing year after year: https://ourworldindata.org/co2/country/china If their share of renewables / nuclear energy were increasing then there would be a decrease in C02 emissions per capita, but that has never been the…

China is building six times more new coal plants than other countries, report finds

https://www.npr.org/2023/03/02/1160441919/china-is-building-...

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#75

Post by pfdietz »

JumpCrisscross wrote: post #72
pfdietz wrote: post #70

Earlier quoted context omitted.

> This is still pie in the sky technology. 4% of the hydrogen production in China is by electrolysis now. Electrolysers there are below $300/kW. You object to this because it's not available, then you point to SMRs, which don't exist now except on slides. And given NuScale's recent disappointments one should not expect the rosy promises of their (or other) SMRs to come true or find much of a market. > Absolutely. If…

> You object to this because it's not available, then you point to SMRs, which don't exist now except on slides Right. Long-term large scale hydrogen manufacturing and storage (presumably as ammonia) is not a thing, not to the tune of several percentage points of primary generation. This is speculative, like SMRs. > Hydrogen + batteries are nicely complementary and enable renewables to undercut new construction nucle…

Hydrogen storage would be underground. Very cheap and more efficient than using ammonia.

If underground storage is not available (lack of proper geology), the scheme could be synthesis of methanol, with oxyfuel combustion (Allam cycle) using oxygen from electrolysis, and with the CO2 stored for recycling to produce methanol. The CO2 and oxygen would be stored as refrigerated liquids.

> (The lithium alone would be orders of magnitude more than what is forecast to be needed for EVs.)

I don't believe this is true, not even close. The US has more than a quarter of a billion motor vehicles. A Tesla has about 70 kWh of storage and about 10 kg of lithium, so that's 17 TWh of storage. An optimal "synthetic baseload" for the US from wind and solar might use 6 hours of battery storage (and e-fuels). US average power production is about 500 GW, so six hours is about 3 TWh of batteries. Even if you multiply that a bit to assume less transmission and need for peaking storage it's still not "orders of magnitude" more than for EVs.) All this is even assuming Li-ion batteries would be used for stationary storage instead of the Na-ion batteries now coming on the market.

Were you assuming many days or weeks of batteries would be needed? That's the beauty of also using e-fuels; the batteries can be reserved for the short term storage they're truly suited for.

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#76

Post by PaulKeeble »

henry2023 wrote: post #19

To this day I think that nuclear is the best way to produce clean and abundant energy. There only one problem. Only governments build nuclear reactors and if you want to innovate in this space you need to deal with these institutions which adds a lot of complexity. Solar on the other hand appeals to the public and can be deployed in large scale facilities. Large scale economics apply directly and we can see that by l…

Lets say I had the knowledge and engineering to make a home scale (say 0.5-1.0 KW) reactor RTG or similar that could be sold as a sealed box you attach to a wall has sensors for various safety measures and just chucks out AC power all day long. At the cost of $5-10k that makes decent economic sense if it would keep going for about 25 year life time. I think that is potentially doable fairly safely with fuels other than Uranium 235.

You can vaguely do this DIY today using the long life radioactive glow sticks and some solar panels and get a constant power device but its very inefficient and too expensive for the power it produces and its half life is too short.

There is I think no viable way to make that business reality. The government intervention would be absurdly high and it would never make it to market even if the cost of the device was economically competitive with a Solar or Wind setup. This is one of the ways Solar and Wind became dominate, they scale really well from the small to the large, especially solar which the panels on the roof of a house are the same in a multiple MW power station.

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#77

Post by afiori »

yongjik wrote: post #38
afiori wrote: post #22

Earlier quoted context omitted.

I agree with your point but as feedback on phrasing saying > Nuclear is orders of magnitude more safer than coal, and has been for 50+ years might cause some skepticism as Chernobyl was in 1986. I am not saying that it is false, but I am saying that it will sound false

Searching for "coal pollution death europe" would give: https://www.wwf.mg/?272333/Dark%2DCloud > It reveals that in 2013 their emissions were responsible for over 22,900 premature deaths, ... https://www.independent.co.uk/climate-change/news/air-pollut... > Pollution from Europe’s coal plants responsible for ‘up to 34,000 deaths each year’ https://iopscience.iop.org/article/10.1088/1748-9326/abecff > The health burd…

I am not disputing this, I am just saying that leaving the argument implicit might be confusing.

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#78

Post by JumpCrisscross »

pfdietz wrote: post #75
JumpCrisscross wrote: post #72

Earlier quoted context omitted.

> You object to this because it's not available, then you point to SMRs, which don't exist now except on slides Right. Long-term large scale hydrogen manufacturing and storage (presumably as ammonia) is not a thing, not to the tune of several percentage points of primary generation. This is speculative, like SMRs. > Hydrogen + batteries are nicely complementary and enable renewables to undercut new construction nucle…

Hydrogen storage would be underground. Very cheap and more efficient than using ammonia. If underground storage is not available (lack of proper geology), the scheme could be synthesis of methanol, with oxyfuel combustion (Allam cycle) using oxygen from electrolysis, and with the CO2 stored for recycling to produce methanol. The CO2 and oxygen would be stored as refrigerated liquids. > (The lithium alone would be ord…

> An optimal "synthetic baseload" for the US from wind and solar might use 6 hours of battery storage (and e-fuels)

This tempers high-frequency variation. The 2% over a full year lower-frequency variation is the problem.

You’re proposing good ideas. But they’re untested and contain fundamental engineering risk. It’s similar to when pro-nuke folk assume SMRs will happen; hence, the analogy.

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#79

Post by com2kid »

loeg wrote: post #71
com2kid wrote: post #61

Earlier quoted context omitted.

> So what? They've invested a large amount of capital in order to avoid low $0.13/kWh residential electricity rates that come from more or less entirely carbon-free sources As per PSE (the power company for the Seattle Metro but outside of Seattle itself), only 23% of the energy sent to surrounding areas outside of Seattle city proper is from hydro. FWIW Nuclear is less than 1%. 46% is fossil fuels, natural gas and c…

We're talking about Seattle residents. We get power from Seattle City Light, not PSE.

As per your original comment

> > Yes, rooftop home solar doesn't make a ton of sense at this latitude and especially not adjacent to this much hydro power.

Latitude is inclusive of the surrounding area, not just the city of Seattle.

Also in general when people refer to a city they are also referring to the metro area around it.

Yes, if you are concerned just about greenhouse gas reduction, and if you live in the Seattle city boundaries, then solar is not a meaningful way to make a reduction.

However many people who live in the Seattle Metro area, but outside the city itself, are shocked to learn how dirty PSE's power is.

For those people, getting solar installed might be meaningful.

And again counter to many people's expectations, Seattle does get enough light to make solar somewhat cost effective, especially with net metering in effect.

Re: China's quiet energy revolution: the switch from nuclear to renewable energy

#80

Post by fspeech »

TeeMassive wrote: post #60
janice1999 wrote: post #4

Earlier quoted context omitted.

is this so hard to explain? - CO2 comes from sources other than energy (electricity) production. - Overall energy usage is increasing, outpacing % growth of renewables.

> Overall energy usage is increasing, outpacing % growth of renewables. This is why I pointed out per capita emissions. If renewables had a bigger proportion, then it would decrease. It didn't. In fact it accelerated.

It takes time for capacity to turn into usage. As the installation in 2023 is so large relative to the total solar capacity the time lag would have more pronounced effect. The number one issue is geographic distribution. The largest installations are in the western provinces, where land is sparsely populated with plentiful of sun and wind. But the consumers of electricity are primarily in the central and eastern provinces. It's not easy to move so much electricity over the large distance, so energy intensive industries need to move west. That will take time. Meanwhile the demands in the east keep growing. Chinese electricity usage is growing significantly faster than GDP, unlike the US.
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