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China's Yanlong: a small nuclear reactor strictly for district heating

cnbc.com

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Re: China's Yanlong: a small nuclear reactor strictly for district heating

#41

Post by dsfyu404ed »

danohuiginn wrote: post #31

And I guess you can just shut it off in summer? Nuclear normally sucks for fluctuating demand, but presumably a 6 month on/off cycle is slow enough to work.

Yes, just insert control rods and wait for things to cool down.

I assume the design is something to the tune of "put a reactor at the bottom of a water filled pit, put a big heat exchanger at the top, pump fluid through the heat exchanger and into the city's heating system and let convection do the rest"

I'm sure with some creative engineering you could do some tricks with attaching something of a specific density that changes with temperature at a rate different than the cooling medium to your control rods you could have a system that self regulates based on the temperature of the water being input (control rods sink when temperature increases) so the system self regulates output.

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#42

Post by sitharus »

jjoonathan wrote: post #29
Retric wrote: post #22

Seems like a much more expensive option than solar hot water heaters. It's $226.7 million for 400MW and "Each 400-MW unit can heat 200,000 homes" so ~1,133$ per home where basic models are selling in Asia for under US$250. They mention it's going to be plugged into existing heating networks, but temperature of 100C is not all that hot.

Do solar hot water heaters work when it isn't sunny?

Yes, the amount of solar heating is affected by the angle of insolation more than the amount of visible sun. They work when overcast just fine, but they won’t work so well in winter at higher latitudes - such as northern China.

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#43

Post by yongjik »

pwaai wrote: post #35
xbmcuser wrote: post #18

Stuff like this makes me feel western countries really underestimate Chinese tech chops. They are able to force stuff on the people that most countries have to cajole and negotiate with their citizens. I get cognitive dissonance from the fact that China is doing it's best to decrease coal usage where as US is tried to increase coal usage.

They have a different perception towards the human life. There's no way anyone would allow this in America because of the potential for catastrophic failures outweigh the benefits. You have to understand the fundamental difference between the two countries on a cultural and government level. Chinese people are more than happy to submit to the government as in the neo-confucian sense, the state is the provider, the fa…

I'm sure the Chinese government doesn't care about human lives that much, but it's irrelevant when talking about nuclear power. The total radiation-related death by Fukushima disaster is estimated to be ~130[1]. For comparison, "A 2013 study by MIT indicates that 53,000 early deaths occur per year in the United States alone because of vehicle emissions."[2]

Most likely, using these reactors and having a nuclear accident will still kill less people than using fossil fuels to heat the same homes and not having any accident.

[1] https://en.wikipedia.org/wiki/Fukushima_Daiichi_nuclear_disa...

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

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#44

Post by msie »

jonwachob91 wrote: post #19
xbmcuser wrote: post #18

Stuff like this makes me feel western countries really underestimate Chinese tech chops. They are able to force stuff on the people that most countries have to cajole and negotiate with their citizens. I get cognitive dissonance from the fact that China is doing it's best to decrease coal usage where as US is tried to increase coal usage.

>> Stuff like this makes me feel western countries really underestimate Chinese tech chops. The west largely underestimates Chinese tech chops b/c they steal so much of our IP... Their ability is evident in the number of Ph.D's they turn out, so why don't they invest in developing their own technology instead of stealing everyone else's? "Catching up" is not an acceptable answer with how much intellectual firepower t…

Lots of original research in the US is done by Chinese PhDs. Have you not done your research? So is it really stealing? Or the US is taking advantage of the best and brightest from China?

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#45

Post by briffle »

danohuiginn wrote: post #31

And I guess you can just shut it off in summer? Nuclear normally sucks for fluctuating demand, but presumably a 6 month on/off cycle is slow enough to work.

Any source of heat can also be used as a source for cooling. My Alma-Matter (Oregon Tech) heats and cools its entire campus with hot geothermal wells.

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#46

Post by dis-sys »

it is just shocking that they did the trial run of the nuclear reactor in Beijing where there are over 20 million people. on the other hand, they were actually allowed to carry out such trial run close to where those most powerful live.

to figure out what other crazy stuff is happening in Beijing, did a quick search and it turns out that there are dozens of experimental nuclear reactors in Beijing, with the first one built in 1964 in Beijing. Tsinghua alone operates many of them.

crazy

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#47

Post by pwaai »

yongjik wrote: post #43
pwaai wrote: post #35

Earlier quoted context omitted.

They have a different perception towards the human life. There's no way anyone would allow this in America because of the potential for catastrophic failures outweigh the benefits. You have to understand the fundamental difference between the two countries on a cultural and government level. Chinese people are more than happy to submit to the government as in the neo-confucian sense, the state is the provider, the fa…

I'm sure the Chinese government doesn't care about human lives that much, but it's irrelevant when talking about nuclear power. The total radiation-related death by Fukushima disaster is estimated to be ~130[1]. For comparison, "A 2013 study by MIT indicates that 53,000 early deaths occur per year in the United States alone because of vehicle emissions."[2] Most likely, using these reactors and having a nuclear accid…

When a government doesn't care about their citizens because there's "too many of them" you get stuff like this (http://www.cnn.com/2016/06/23/asia/china-organ-harvesting/in...). So, of course they are going to be more willing to ignore basic human rights to achieve their goals. I'm not saying the US is innocent either, privatized prisons targeting African and Latin Americans to benefit shareholders of those private companies is legalized genocide (how many fatherless black children growing up in the ghetto are equipped to adjust to mainstream society)?

There is a lot of misinformation regarding the Fukushima disaster if you dig around and the long term effect on the population near that region is not being addressed and being covered up. Their exposure to the radiation will not show immediately as in most nuclear disasters but at a delayed rate after it takes a toll on their bodies. This type of silence is typical of the Japanese where they will hide mistakes for as long as it's tolerated (ex. Kobe Steel etc).

I don't think it's safe to look at Fukushima and say "oh only 100 ppl died its safe" to justify proliferation of nuclear reactors because the damages are not limited to those loss of life. Germany understands this and lot of European countries are moving away from Nuclear power altogether.

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#48

Post by volgo »

seanmcdirmid wrote: post #27
jobu wrote: post #20

Earlier quoted context omitted.

China has been run by technocrats for the last couple decades. Most of the current leadership has more of a political background, but president Xi Jinping has a chemical engineering degree. http://www.scmp.com/news/china/policies-politics/article/211... "from 1997 to 2007, all of the top leaders sitting on the innermost Standing Committee shared an engineering background"

Xi Jinping never practiced as a chemical engineer, however, being an anointed princeling destined for officialdom (and of course, he had to delay his education because of the CR). Hu Jintao and Jiang Zemin are better examples, actually having worked as engineers for a number of years before becoming politicians.

Hard to use princeling in the sense to convey privilege here. His father was sentenced to labor camp during the Cultural Revolution and he himself worked in forced labor for seven years:

"The father was detained and imprisoned and spent 16 years in a labor camp, plunging the family into poverty. During the Cultural Revolution, a 15-year-old Mr. Xi was banished to a poverty-stricken village in northern China where, for seven years, he labored with peasants, eating corn chaff bread and sleeping in a flea-infested bed."

http://www.nytimes.com/2012/02/13/opinion/chinas-heir-appare...

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#49

Post by seanmcdirmid »

Retric wrote: post #38
seanmcdirmid wrote: post #28

Earlier quoted context omitted.

Solar doesn’t work that well in northern China during the winter because there is hardly any sun. Even discounting the pollution, the area would be mostly foggy and overcast, it would be like trying to use solar in Seattle. An apartment complex I lived in had solar hot water and I absolutely hated it, I could never take a “hot” shower during Beijing’s cold winter, just a luke warm one.

Implementation can make a huge difference, people do install these systems in Alasca and then supplement for a few weeks in the middle of winter which is still a huge fuel savings and cost reduction. But, if your going to base this on a central location then sizing the system and maintain the desired temperature output is simplified.

There isn’t much space for solar panels, so sizing is intrinsically constrained. Also, these are 32 story towers with approximately 130 units...it’s not rocket science why it doesn’t work out.

They were definitely not supplementing enough.

Re: China's Yanlong: a small nuclear reactor strictly for district heating

#50

Post by seanmcdirmid »

volgo wrote: post #48
seanmcdirmid wrote: post #27

Earlier quoted context omitted.

Xi Jinping never practiced as a chemical engineer, however, being an anointed princeling destined for officialdom (and of course, he had to delay his education because of the CR). Hu Jintao and Jiang Zemin are better examples, actually having worked as engineers for a number of years before becoming politicians.

Hard to use princeling in the sense to convey privilege here. His father was sentenced to labor camp during the Cultural Revolution and he himself worked in forced labor for seven years: "The father was detained and imprisoned and spent 16 years in a labor camp, plunging the family into poverty. During the Cultural Revolution, a 15-year-old Mr. Xi was banished to a poverty-stricken village in northern China where, fo…

Yes, but he was quickly rehabilitated after Mao’s death, and anyways, everyone was in the same boat.

Xi is the canonical example of his so named “lost generation:” forced to leave high school early, sent down to the country side, rehabilitated and given basically an cursory education as a legacy admit to Tsinghua. He is the first Chinese leader since Mao who can’t speak a word of English, less educated than his predecessors, more autocratic (vs. Hu), less outspoken (vs. Jiang) and more on ideological message.

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