Thread by @simonahac

🤓the nuclear power sector is hoping for a revival with the advent of "small modular reactors".

@NuScale_Power is arguably the closest to a commercial #SMR product, but is also providing a clear example of the challenging and long road ahead for the sector.

.@NuScale_Power aims to reverse trend of increasing nuclear project costs by utilising:
• passive safety systems / simpler design — safely do away with several expensive systems
• modular, factory fabricated reactors — capturing economics of factory manufacturing / repetition

in 2015 @NuScale_Power signed up a first customer, #UAMPS, to build a nuclear power plant near idaho falls for a 2024 delivery.

UAMPS @SmartEnergy1 is a consortium of community-owned (ie. municipal) power systems in the “intermountain west” of the US: utah & neighbouring states.

that schedule slipped to 2026, and recently the 37 member communities of #UAMPS’ “carbon free power project” were advised that the schedule has slipped again.

@NuScale_Power's first unit is now scheduled to power up in mid-2029, with plant completion in 2030.

the expected cost has also increased, jumping from ~US$3.6bn to $6.1bn.

being a first-of-a-kind (FOAK), the project naturally carries higher project risk and costs than future (“N-of-a-kind”) projects, so to help defray this, the US dept. of energy @ENERGY is kicking in $1.4bn.

one cause of the recent delay & cost increases is the change in cooling design.

since long-term water availability is an issue, the reactors will now be “dry cooled”. this uses far less water than once-through or recirculating cooling but incurs an energy efficiency penalty.

the current costs are based on a “class 4” estimate of the total project — ie. the cost estimate still has a wide margin of error.

a final “class 1” cost estimate isn’t scheduled to be completed until 2024Q3.

appropriately, the project members have a series of “off ramps” — ie. they have multiple opportunities to leave the project.

…and prior to the final go-ahead, if the project is too expensive (LCoE > $55/MWh target) the members can withdraw and get their investment back.

in the last few weeks two members have withdrawn from the project, including the city of logan (pop. 51,542), see below, and one has apparently joined.

cachevalleydaily.com/news/archive/2…

…the @UtahTaxpayers association has run a campaign urging project members to withdraw from the project.

sltrib.com/news/politics/…

on 19 august, the city of @LosAlamos, new mexico — home of the lab that developed the atomic bomb & still very much involved in maintaining the nation's nuclear stockpile, now with supercomputers rather than atmospheric tests — chose to stay in the project, by a vote of 3 to 2.

in total, members of the project have subscribed to 200MW of the 684MW (net) power available.

before starting construction, #UAMPS and @NuScale_Power will need to find more subscribers, or downsize the project — however downsizing would likely drive up the unit costs of power.

.@NuScale_Power's #SMR design is expected to receive certification from the @nrcgov next month — but that won’t be the end of the road for certification.

eg. they still need approval for increasing unit size from 50MW to 60MW, and…

at least two potential safety issues have been noted during certification — however the @nrcgov's advisory committee on reactor safeguards has recommended awarding certification, which indicates that those issues are readily solvable with design changes.

sciencemag.org/news/2020/08/s…

critics note that the specific reactor design has never been fully tested.

@NuScale_Power produced a 1/3 scale model & tested parts of the design using an electrically heated (non-nuclear) core.

the first reactor test will be years after the 12th reactor is manufactured. 😬

my thoughts: @NuScale_Power have one hell of a needle to thread.
• schedule slip
• cost overruns
• "nuclear naïve" customer
• subscriptions are low and brittle
• certification hurdles
• technical risks
• competitor technologies moving rapidly and deploying now

that said, i hope @NuScale_Power is successful — the tech would provide options that some markets *may* need — though it’s a bit crazy that regional community ratepayers will end up carrying so much FOAK risk.

large utilities and/or government make better first customers.

the image at the top of this thread is obviously an artist's impression. the plant could just as well look like this:

(but if/when they do build, i hope they go for the "jetsons" version.)