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First new U.S. nuclear reactor since 2016 is now in operation

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Re: First new U.S. nuclear reactor since 2016 is now in operation

#361
post #184

Earlier quoted context omitted.

I remember reading some article that said we could offset all of human emissions by painting Vermont stark white or something along those lines. Covering a desert in solar panels seems like the exact opposite of that plan.

If you ignore all other variables, then of course the situation looks like what one variable would make it do. Would covering a desert in solar panels cause more thermal solar absorption in that area than would otherwise happen? Yes. But if we're optimizing for "offsetting the heating effect of human GHG emissions", then installing 4.5TW of solar (about 4x what has been installed worldwide to date) would have a much…

Has this actually been quantified? Earth's albedo is a critical factor in the portion of the sun's energy that is rejected into space, just as GHG incidence in the atmosphere is.

In theory, darkening a portion of the Earth with high albedo (snow, sand) is worse than darkening a portion of the Earth with low albedo (roads, roofs, forest). Then it should be better to use a greener area for solar panels so long as the capacity factors would be similar.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#362
post #147

This caught my eye: "Prior to Vogtle Unit 3, the last nuclear reactor to start in the United States was Watts Bar Unit 2 in Tennessee. Construction on Watts Bar 2 began in 1973 but was suspended in 1985. Work resumed in 2007, and the reactor came online in 2016." More on that here: https://en.wikipedia.org/wiki/Watts_Bar_Nuclear_Plant#Unit_2

I can't even imagine how you'd get the parts, and they probably can't change the plans either. Ok so I decided to look into it a bit more, and here are some interesting details from documents on the nrc.gov and EIA.gov: Here's some context for what was happening in 1985, from the eia: >"As a consequence of the identification of a large number of deficiencies shortly before the WBN Unit 1 license was expected to be is…

TVA - Not the Time Variance Authority I take it?

I was wondering how that was powered.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#363

Earlier quoted context omitted.

One kilogram of uranium-235 (50 cm^3) can theoretically produce about 20 terajoules of energy. One square kilometer of solar panels can theoretically produce the same amount (as 50cm^3 U235) in a day. I'll take this bet. Edit: Tried to edit the edit but somehow deleted the rest of the edit. It was something to the tune of how a big problem with renewables is the fact that peak solar production does not match peak ene…

> One kilogram of uranium-235 (50 cm^3) can theoretically produce about 20 terajoules of energy. One square kilometer of solar panels can theoretically produce the same amount (as 50cm^3 U235) in a day. Does the US have more 50cm^3 sized blocks of U235, or more square kilometers of land with low land values and high annual insolation? There's an estimated 6 million tonnes of mineable uranium reserves in the world [0]…

40 million acres are used to grow corn for ethanol. This is 162,000 square kilometers. This can produce 3.24 exajoules of energy.

Also, solar panels don't need any land. There are so many places we can install solar without 'consuming' land. They can be roofs, floating on tops of lakes and reservoirs with the added benefit of preventing evaporation, agrivoltaics combined with farmland, vertical panels, superfund sites, deserts, along the highways, etc.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#364
post #119

Earlier quoted context omitted.

Nuclear is baseload and is the exact opposite of "instantly fired up". Best tech for that is gas or battery.

Cant control rods can be lifted or inserted to meet demand?

Usually you'd vary the concentration of boric acid being injected in the reactor's core instead, since that doesn't involve wear and tear on safety-critical elements of the reactor.

Nuclear reactors absolutely can vary their output to match demand, this is what France has been doing for 50+ years (and what Germany was doing before switching back to coal). It's not as reactive as coal/gas, but you can still vary within 30-100% of output power at a speed of 5% change per minute. Way more than enough to react to 1-day-ahead forecasted supply/demand, and way more than enough to react minute-by-minute if you've got a tiny bit of storage to stabilize the grid's frequency (e.g. pumped hydro).

Re: First new U.S. nuclear reactor since 2016 is now in operation

#365

Earlier quoted context omitted.

Sustainable fuels. It's the solution long haul aviation is coalescing around.

Synthetic fuel has a lot of difficulties. One, it requires hydrogen as an input which is typically produced through steam reformation [1], a process that emits CO2. Electrolysis is less efficient and hard to scale as equipment is subject to intense corrosion. Second, CO2 is at very low concentrations in the atmosphere. Direct atmospheric carbon sequestration is expensive and slow. The biggest startup in the synthetic…

We need to massively scale up green hydrogen production under basically any scenario where climate change is avoided. Hydrogen is an input for many industrial and agricultural processes.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#366

Earlier quoted context omitted.

Given that we ship cargo in incredible amounts across all oceans, ranging from liquids, bulk to containers and cars everyday with zero nuclear-powered carho vessels, calling nuclear your only option is odd.

In case it wasn't clear, I'm talking about carbon-free propulsion options. Batteries don't have the energy capacity required for long distance shipping, and their weight is a big issue for ships. 300 mile range is fine for an EV, it's not for a ship.

You can create a fuel with solar energy and use it in the ship's engine. Hydrogen or whatever will be available.

But heavy oil is much cheaper and will be used forever untill gasoline/diesel cars/trucks will pass away.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#367

Earlier quoted context omitted.

Chinese nuclear is not competing very well. There's a minuscule amount of it planned, only like 50GW over the coming decades. This is not even a drop in the bucket compared to what China are doing with batteries, wind, and solar.

"China has 55 plants with 57GW in operation, 22 under construction with 24 GW and more than 70 planned with 88GW." https://en.wikipedia.org/wiki/Nuclear_power_in_China So the current plans are for roughly tripling installed capacity.

China built out 180-230 GW of solar last year. They deployed more in one year than the total installed base of nuclear that China is expected to have by 2030.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#368
post #254

Earlier quoted context omitted.

> Construction on Watts Bar 2 began in 1973 but was suspended in 1985. Work resumed in 2007, and the reactor came online in 2016. That seems to be common with nuclear power plants. The latest one near where I live (Angra 3) has been under construction since 1984, and it should be complete in a few more years if it doesn't pause again; construction of the previous one (Angra 2), according to Wikipedia, started in 1976…

Well the Three Mile Island accident was in 1979, so I imagine that created a lot of resistance to continued construction across the country. https://en.wikipedia.org/wiki/Three_Mile_Island_accident

Three Mile Island was a partial meltdown. It wasn't just a fender bender.

Re: First new U.S. nuclear reactor since 2016 is now in operation

#370

If I was a betting man, I would put money down that Vogtle 4 is the last nuclear reactor that gets built in the US. Solar and batteries are just too cheap for nuclear to compete. The world will be installing a terawatt of solar capacity per year soon. *excluding research or military reactors of course.

One kilogram of uranium-235 (50 cm^3) can theoretically produce about 20 terajoules of energy. One square kilometer of solar panels can theoretically produce the same amount (as 50cm^3 U235) in a day. I'll take this bet. Edit: Tried to edit the edit but somehow deleted the rest of the edit. It was something to the tune of how a big problem with renewables is the fact that peak solar production does not match peak ene…

Nuclear is the way forward. It’s a damn shame hippies stopped us from leveraging it. We literally wouldn’t have climate change if we kept increasing nuclear power plants in the 70s. It’s just a no brainer. Solar and wind are great but the amount of power they generate may as well be 0 compared to nuclear.
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