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Cake day: June 11th, 2023

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  • I was curious, so I checked to see the current longest ultra-high voltage dc transmission line:

    The Changji-Guquan ultra-high-voltage direct current (UHVDC) transmission line in China is the world’s first transmission line operating at 1,100kV voltage.

    Owned and operated by state-owned State Grid Corporation of China, the 1,100kV DC transmission line also covers the world’s longest transmission distance and has the biggest transmission capacity globally.

    The transmission line traverses for a total distance of 3,324km (2065 miles) and is capable of transmitting up to 12GW of electricity.

    As a general rule of thumb, HVAC lines will be somewhere around 5-6% line loss per 1000kms, and HVDC somewhere around 3%/1000kms



  • People keep saying this, but it’s not accurate.

    An EPR is an EPR, the same with the AP1000. There are only very minor differences between installs, usually things that will help ease of construction or reliability on future builds. Both are GEN III+ designs, greatly simplified compared to previous generations, with fewer pump, valves and pipe-runs. They also shortened pipe runs where possible. They also have large, factory-built assemblies that are shipped to site, ready to “bolt” in, which should have reduced site construction time.

    Where major changes do happen, it’s with the balance of plant infrastructure, which is site dependent. Location of access roads, where the switchyard is installed, where cooling water is accessed , etc will never be the same between sites. Nor will the geotech information. So a lot of mainly civil and structural design and fabrication will always be site specific.

    The KLT-40S reactor is a variant of the KLT-40 reactors developed for and installed in the Taymyr icebreakers back in the late 1980s. It should have been cheap, as it’s a known quantity with a long track record.





  • That’s just not true. The Westinghouse AP1000 was given type approval in 2011. It’s what is referred to as a GEN3+ reactor. A lot of R&D was put into simplifying the design, reducing the number of pipe runs, valves, pumps etc compared to GEN2 reactors. It also used large sub assemblies that were factory built off-site then moved for final assembly.

    In theory they should have been cheaper to build, but they weren’t. Large assemblies that don’t fit together properly need a lot of very expensive site time for rework. There were other issues on top of that, which just compounded the assembly problems. It’s how Vogtle ended up going from $12B to $30B+, and V.C Summer went from $9B to an estimated $23B when the project was cancelled while under construction.

    The EPR units from Areva were similar GEN3+and received type approval in the early 2000s. They had similar cost overruns, for similar reasons.

    I have strong reservations about SMRs. So far the cost/MW is about on par with traditional reactors while the amount of waste increases by 2 to 30x traditional reactors depending on technology used.

    There are reasons why reactors moved from 300-600MW units to 1000MW+ in the first place. The increased output would cover what was thought to be marginal increase in costs. That turned out to be at least somewhat true.




  • Just like assuming a perfectly spherical cow, or a frictionless surface, you can completely ignore the economics, the massive cost and schedule overages to make nuclear work.

    Flamanville-3 in France started construction in 2007, was supposed to be operational in 2012 with a project budget of €3.3B. Construction is still ongoing, the in-service date is now sometime in 2024, and the budget has ballooned to €20B.

    Olkiluoto-3 is a similar EPR. Construction started in 2005, was supposed to be in-service in 2010, but finally came online late last year. Costs bloated from €3 to €11B.

    Hinkley Point C project is two EPRs. Construction started in 2017, it’s already running behind schedule, and the project costs have increased from £16B to somewhere approaching £30B. Start up has been pushed back to 2028 the last I’ve heard.

    It’s no different in the US, where the V.C. Summer (2 x AP1000) reactor project was cancelled while under construction after projections put the completed project at somewhere around $23B, up from an estimate of $9B.

    A similar set of AP1000s was built at Vogtle in Georgia. Unit 3 only recently came online, with unit 4 expected at the end of the year. Costs went from an initial estimate of $12B to somewhere over $30B.

    Note that design, site selection, regulatory approvals, and tendering aren’t included in the above. Those add between 5-10 years to the above schedules.





  • Something Ryan didn’t mention was pumping losses, which increase at an increasing rate with engine rpm, so efficiency suffers.

    Different engine designs have different sweet spots. My V85 is perfectly happy at 3000rpm around town, but it only revs to 8000 or so. My FZ6 wouldn’t really be happy at anything under about 5000rpm, but redlined at 14.5k.

    You just have to get used to the engine you have and have some mechanical sympathy: don’t lug it, but you don’t need to rev the tits off it either.



  • Very early on in my career in consulting engineering, I had an architect tee-off on me for changing the ceiling heights of the office space she’d designed.

    I’m electrical, all I was concerned with was circuiting her lights, that was it. I had documentation showing that I’d worked off of exactly the same ceiling heights she had sent me. Heights that she’d apparently changed somewhere along the line without informing the client, who was an international conglomerate, and notoriously picky to work for.

    That could have blown over, had she not berated me over email while CCing the client, my management and just about anyone else involved with the project. I made sure to “reply all” showing where the change had happened. She was replaced on the project the following week.

    After that I stuck to industrial projects, where the buildings were non-descript concrete and steel boxes with no architectural involvement.



  • Dad had an interesting career. Started as an office clerk for a railway with only high school education. Then he got into using an IBM 650 (IIRC) for doing freight rate calculations. How he managed that transition, I have no idea. He didn’t care for being cooped up all day flipping switches, dealing with punch cards and tapes.

    He switched to marketing and got on there very well and retired after 37 years as a regional director.

    He always has a book on the go, even now at 83. He has an eclectic pile of them that he kept, from Zane Grey to an early history of the Civil War written around 1870.



  • Back when I was in junior high in the early 1980s, I found a copy of Atlas Shrugged on my father’s bookshelf, and started reading it. I can’t remember how far I got into it, but I do remember thinking it was just awful in just about every way: story, writing, pacing, everything.

    I asked Dad about it, “Oh, that. It’s terrible, isn’t it?” A friend had given it to him. Neither one of us finished reading it and after that it ended up at a book reseller.
    On the plus side, he’d gone through his books and gave me James Clavell’s Shogun to read, which was an awesome novel.