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Nothing like this will be built again (2002)

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Re: Nothing like this will be built again (2002)

#231

Post by philipkglass »

cesarb wrote: post #199
hkt wrote: post #146

Earlier quoted context omitted.

Wind turbines do though - neodynium, if memory serves.

Do they require neodynium permanent magnets? AFAIK, there are generators (including big generators at hydroelectric power plants) which use electromagnets instead. The same applies to electric motors; there are some which use permanent magnets, and some (induction motors) which don't.

The majority of wind turbines use electromagnets.

You can see it in this industry report graphic:

https://nawindpower.com/gwec-tier-one-turbine-suppliers-gain...

"Conventional drive" and "Direct drive - EESG DD" add up to 75.5% market share. These designs don't use permanent magnets.

Re: Nothing like this will be built again (2002)

#232

Post by soperj »

Gwypaas wrote: post #230
soperj wrote: post #226

Earlier quoted context omitted.

Current price of Nuclear in Ontario (generated by CANDU reactors) is 5.9 cents per kWh.

That is very expensive. Given that they came online in the 70s and early 80s we can assume the initial capital investment is paid off by now and that cost is only the marginal running cost. (OPEX) Now, currently we are building solar farms in desert areas for ~1.5 cent per kWh. Including both CAPEX and OPEX. On-shore wind is built at ~3 cents per kWh and ~6 cents per kWh for off-shore. This is where the explosion of…

Sorry, that's what the consumer pays. It includes transmission to the home.

Re: Nothing like this will be built again (2002)

#233

Post by valarauko »

grogenaut wrote: post #215
valarauko wrote: post #182

Earlier quoted context omitted.

> That said roman concrete is a thing they've been chasing for a while Roman concrete isn't some magical substance that we're hoping to replicate - we already know how it works - it just would really suck for the type of building projects we have now.

Aah, I thought we were trying to replicate it or one of it's properties still, maybe in the context of modern concrete. Would love to know more.

Unfortunately a lot of the discussion online regarding Roman concrete veers uncomfortably into a rather, shall we say, "supremacist" angle. For a level discussion about Roman concrete, I found this to a nice place to start.

http://engineeringrome.org/understanding-roman-concrete/#Anc...

Re: Nothing like this will be built again (2002)

#234

Post by credit_guy »

jacquesm wrote: post #220
pavlov wrote: post #104

How does Torness compare to new European nuclear construction like Olkiluoto 3 in Finland, activated last month? Olkiluoto 3 is a 1600 MW reactor, so on paper it's a much bigger unit than the 600 MW reactor described here.

Totally different principle of operation (boiling water versus gas cooling).

In that case how about the Helium-cooled reactors that were just hooked to the grid in China 3 weeks ago?

[1] https://www.world-nuclear-news.org/Articles/Demonstration-HT...?

Re: Nothing like this will be built again (2002)

#235

Post by joshvm »

sloucher wrote: post #135
joshvm wrote: post #51

On safety - one of the places I had the opportunity to visit had a car park where you were only allowed to reverse in. I'm not sure if it was a holdover from a previous establishment, but I think they kept something on site that was volatile enough (like a lot of gas) that if a swift evacuation was required, they didn't want people futzing around getting out of spaces.

My wife visited Torness (the plant in the article) for a meeting with one of the managers. She went through reception, got her badge, and was on her way up the stairs to the meeting room when the receptionist shouted at her. "Maam! MAAAM!... please hold the handrail". They're nuts about safety - and a good thing too, speaking as someone who lives relatively close-by.

This was also the case at this location. Alongside discipline around showing passes, scramble pads on doors and so on. It was even the case in the office building (we were nowhere near anything obviously dangerous). Super strong safety and security culture.

Re: Nothing like this will be built again (2002)

#236

Post by bshanks »

JetSetWilly wrote: post #156
tda wrote: post #97

I bet the Fukushima backup power system would have fit this explanation perfectly: > in addition to the grid connection, there are four twelve megawatt diesel generator stations spaced around each corner of the plant -- each with two generators, any one of which is able to provide operating power to keep the reactor's safety systems working. Unfortunately for Fukushima, all generators were flooded by a single Tsunami…

Interestingly hunterston - a nuclear power station on the west coast of Scotland - had a failure of its backup diesel generators. Wikipedia describes it as: > In December 1998, an INES Level 2 incident occurred after severe winds and sea spray disabled all four power lines to the site during the Boxing Day Storm of 1998. After multiple grid failures in a short period of time, emergency diesel generators failed to sta…

Seems like a bit of a misnomer if the "passive" cooling had to be activated.

Re: Nothing like this will be built again (2002)

#237

Post by mcguire »

"(Which isn't likely; in addition to the grid connection, there are four twelve megawatt diesel generator stations spaced around each corner of the plant -- each with two generators, any one of which is able to provide operating power to keep the reactor's safety systems working.)"

I've heard that before, somewhere.

Re: Nothing like this will be built again (2002)

#239

Post by pfdietz »

mydeskistoosm wrote: post #162
soperj wrote: post #116

Earlier quoted context omitted.

passive fail-safe already existed 20 years ago. CANDU Reactor is exactly that. Doesn't even need enriched uranium.

So what happened? Why aren't we in a world of abundant energy?

It's because safety wasn't the obstacle to nuclear energy, cost was.

Also, I don't think passive safety of CANDU is what's meant by passive safety of HTGRs. The latter can survive losing cooling and everyone just walking away (in theory); I suspect the CANDU melts down in that situation, even if the chain reaction does stop.

Re: Nothing like this will be built again (2002)

#240

Post by pfdietz »

soperj wrote: post #226
Gwypaas wrote: post #225

Earlier quoted context omitted.

Turns out a steam based thermodynamic cycle is expensive even with "free" energy.

Current price of Nuclear in Ontario (generated by CANDU reactors) is 5.9 cents per kWh.

Now tell us what happened the last time they tried to buy more nuclear plants.
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