Oklo has filed first combined license application (COLA) with the NRC since 2009 1

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  1. “Oklo expects to spend approximately $10 million to build the complete power plant and structure. That cost doesn’t include fuel or… etc., etc., have a life of 20 years.”

    20x365x24x1.5=262,800 MWh-e (the limit of possible)

    Typically an FSAR chapter 4 would give enough fuel design information for hand calculations; Oklo FSAR simply states that peak burnup is less than 10GWD/MTM – about 20% of what is seen in a LWR.

    20x365x24x4/24 = 29200 MWD
    Core Mass = 29200 MWD / 10GWD/MTM = 3 Tons HALEU (low estimate)

    Using the defaults https://www.uxc.com/p/tools/FuelCalculator.aspx 3000 Kg HALEU will cost $16M.

    Year-average wholesale cost of power in Eastern PJM: $24/MWh (bad example, but…)

    Revenue from 20 years of operation at $24/MWh = $6.3M << $10M + $16M

    Cost of wholesale power must be $159/MWh to pay off $26M @ 5% interest in 20 years; mortgage payment is $238/hr.

    That is WITHOUT insurance, without any employees. Adding 1 employee at $62/hr brings cost of making 1.5MW to $300/h – $200/MWh.

    Maybe this isn't unreasonable when you consider New Jersey gives a "Solar Renewable Energy Credit" (SREC) for each MWh generated by solar panels; the going rate for an SREC in New Jersey is $225. In a socialistic, manipulated, yet [still] 'free' market (sic) where big LWRs can barely keep their chins above water, electricity is simultaneously worth $24/MWh and $225/MWh, while my bill says $8/MWh retail (before T&D). Dividing my bill by usage yields $18/MWh… It’s incredibly complicated; there are capacity payments, and other devices making straightforward analysis difficult.

    1. @Michael Scarengella

      TMI would never have been able to be built and operated to supply a village of 2,000 people in northern Canada. There are between 50 and 100 communities in that region with power needs that might be served by a system like Oklo that can fit onto modest sized building on a mostly vacant site occupying less than an acre of land.

      Currently, those villages get their electricity from diesel generators burning distillate fuel oil that is either trucked, barged or flown it at great expense.

    2. I have an error in the section about my bill. My bill says $80/MWh retail before T&D and I pay about $180/MWh. Factor of 10 there.

      1. What’s a factor of ten among friends?

        At a delivered cost of $180/MWh in a well served area of the grid, I would hope you might agree that Oklo’s costs don’t look so outlandish. Remember, quoted costs are for an FOAK, “show room floor” generator that can be located close enough to customers to minimize transmission costs.

        Oklo isn’t low-balling costs to attract customer interest. Its plan is to design, build, own and operate a fleet of generators. Its revenue will come from selling products from those generators – heat, electricity, and perhaps additional products like H2 or isotopes.

        I also challenge your fuel cost assumption. As you pointed out, Oklo’s design results in low burn up. Why assume there is no residual value for the input fuel material after 20 years of use? It’s not fresh material at the start of life, it will be only slightly used at the end of life.

        DOE is leasing the material under a special program, but why not consider a leasing model for Nth of a kind?

    1. Hmm. If I had $26M and lived in Nome AK, well… I wouldn’t live there anymore. What economic activity justifies tying up $26M for 20-years in Nome AK? Crabbing? Nome is on the coast, so I assume they can receive boats of fuel oil. My calculations are hugely forgiving and should be considered an absolute floor – just enough math to give away the punchline.

      1. Even though Nome is on the coast and has an easier time getting fuel delivered than interior towns and villages, its electricity costs are high enough to indicate that Oklo could profitably supply their needs.

        Now imagine the economics for Nth of a kind generators in places where fuel deliveries are more difficult (costly). Consider fact that SOME people really like clean air and water and don’t like depending on noisy, smelly, polluting diesel generators.

        Getting excited yet?

  2. I have only gone through a portion of the document, but what is the power transmission system? Stirling engines? That is what KRUSTY uses.

    The “No licensed operator” part might be a hard sell. It is sort of like saying “no person in the operating room for the surgery will have a medical degree”.

    The low fuel burnup that has been discussed is somewhat disappointing.

    1. Okay. The FSAR says a Rankine thermodynamic cycle using supercritical CO2 as the working fluid, not Stirling engines.

  3. This just shows that it’s not difficult to put together a licensing case for a reactor that is too small to be much of a concern. This design is (large) research-reactor size.

    The challenge is not making the safety case, it’s the economics. With a 1.5 MW output and $3M/year operating costs, the electricity costs 23 cents/kWh, assuming that the reactor runs continuously at 100% power for the entire year — and that’s just the operating costs.

    To put this in perspective, the current nuclear fleet provided electricity at 3 cents/kWh in 2019, and this includes the costs of fuel, operation, and all capital expenditures (upgrades, replacements, and whatnot).

    Still, it’s got to be cheaper than importing diesel to a remote site.

    The real challenge will be to make good on promises on costs once this design begins to be deployed.

    1. @Brian Mays

      Welcome back. I’ve missed our conversations. (Of course, my failure to publish is a big contributor to the lack.)

      Oklo is pointing the way to a licensing paradigm that can be used when reactors are small enough so that the safety case isn’t a challenge.

      Their projected operating cost for the specific project at INL are not reflective of the cost for a commercial unit. They pay their employees pretty well, but $3 million/yr for a full time, on site staff of 2 would mean some really hefty paychecks.

      That projected O&M cost is for a demo that will be running experiments and tests.

      1. Hi Rod,

        I hope that you’re enjoying your retirement in Florida. I too have missed our conversations and seeing you every so often at ANS events.

        You wrote: “Oklo is pointing the way to a licensing paradigm that can be used when reactors are small enough so that the safety case isn’t a challenge.”

        You’re preaching to the choir. I’ve spent over 15 years (on and off) working on a design that one person from the NRC described as “too safe to regulate.” That doesn’t mean that there isn’t any paperwork involved, however.

        I’m back to doing that full-time. I’m now a technical expert in Framatome’s advanced reactor efforts (part of Framatome North America’s advanced reactor group). We’re closely following everything that is going on these days in advanced reactor space, including Oklo. I was supposed to be interfacing with my colleges in Europe this week, but the whole pandemic thing has put everything on hold.

    2. Exactly; the concept of micro-reactor presents the mathematical upper limit of the cost of terrestrial electricity – it could only be more expensive in orbit. Even if FOAK construction costs are 200% serial construction costs, the reactor needs $16M of uranium, and that doesn’t include fabrication of a fuel product and integral heat exchanger with no historical precedent. To think it will chug-along without staffing is pathologically naive. To think it will sail through the NRC (which is staffed, in part, by guys like me) is quite naïve – but maybe as you say “too small to be of concern” – still it is at least 3 tons of HALEU that requires safeguarding. At the supposedly optimum tails assay reported by UxC for 20% enrichment, 0.167, this is 36.1:1 feed:product. HALEU is mindbogglingly wasteful – and they are depleting this uranium to what a LWR fuel assembly sees in 250 days (10 GWD/MTM) over 20 years?!?!?!?!

      “Still, it’s got to be cheaper than importing diesel to a remote site.”

      And there is the business case, which might I add, is actually an assumption.

      The labs have subsisted for an entire generation on building nothing and printing paper. I’m happy they are trying to build something like in the old days. Unfortunately, the technologies in development now do nothing to stretch the fuel cycle or reduce the cost of electricity – they all do the opposite (Kairos, NuScale, Oklo). The most amazing thing INL has done in the last decade is bringing TREAT back online. https://www.youtube.com/watch?v=h0o4P_F4s9s

      What about Idaho’s 1995 Settlement Agreement with regards to getting commercial nuclear fuel into the state of Idaho? https://www.deq.idaho.gov/inl-oversight/oversight-agreements/1995-settlement-agreement/ Quoting an engineering consultant from Idaho Falls: “Noteworthy is that Idaho National Laboratory can’t even get research quantities of nuclear fuel into Idaho. Why? The 1995 Settlement Agreement and DOE’s failure to remove/process nuclear waste. ”

      1. Ah … another cynic. You and I are kindred spirits.

        My cynicism was earned by working in AREVA’s Federal Services group for almost a decade. I knew folks who retired after a career of working on a dozen or so DOE projects, and yet not one of these projects concluded by achieving its goal.

        DOE projects are like old soldiers: They never die … they just fade away. Consider Yucca Mountain, a ghost that still haunts the federal budget to this day.

  4. The present Oklo design is conservative to the point of being economic in remote places where only diesel electricity. But there is more to consider.

    The most recent DOE Gain award grans this research for Oklo’s benefit. Maybe the 1.5 Me will be 2.0 Me after this research is completed.
    NE-20-23491, Addressing Gaps in Legacy Data on Fuel Steel Interactions The proposed solution is to conduct additional experiments and provide targeted data to support the licensing of new reactor designs, which will allow reactor developers to reduce significant conservatisms they must now take to avoid Fuel-clad chemical interactions (FCCI). https://gain.inl.gov/SiteAssets/2020VoucherAbstracts-2ndRound/Abstracts/NE-20-23491_Oklo-AddressingGapsinLegacyDataon%20FuelSteelInteractions.pdf

    It seems remote cold places are the natural customers for Oklo. Selling heat would be a natural additional income for a plant where Aurora can be seen.

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