I think this is why they call it baseload. Yes it costs the same, used or unused... but it's always there, ready to be used. This is its strength, not a defect.
> If you really want 100% reliability out of a primarily-solar grid
But no reasonable person wants that. They want "100% reliability, and who cares where it comes from". If you're environmentally minded, you can tack on a "with no carbon"... but even that isn't the same thing as a "primarily solar grid".
Way back when, they realized that grids had a base load below which it never dropped. They realized that if they designed some of their plants without the expensive features which allowed them to be turned on and off quickly, they could build plants cheaper.
You don't design grids for base load, you design grids for peak load in all scenarios. If you can handle peak, you can also handle base.
Baseload is for cost optimization. And nuclear is a horrible way to optimize cost.
Yes that might happen. But it'll happen at a number much greater than 50X. And it's a problem that'll only happen if we solve the global warming problem first.
> right now only about 30% of our energy consumption (and therefore emissions) is electricity. If we want to cut emissions to zero, we need to transition most of our energy use to electricity. The big culprits are transportation, steel, concrete and fertilizers. That's a factor of 3.
But we mostly use fuels that are 30% - 60% efficient plus wastage for production, refining and transporting. Over 2/3rds of the energy we use gets wasted as heat. So we've got a factor of 1/3 to cancel out your 3 here. It's not completely efficient so it's actually about 1.2X, not 3X.
> Then we want to increase everyone's standards of living to match the current standard of living of the average American or European person.
Yep, that's a good 3X, if not more there. But unfortunately it's going to take decades to accomplish this.
> Each SpaceX Starship launch puts about 5000 tons of CO2-equivalent emissions in the atmosphere. If, as Elon wants, we end up having hundreds or thousands of launches per day, and we want these launches to be net zero, then we need to find a way to manufacture hundreds of millions of tons of synthetic fuel each year.
> Each SpaceX Starship launch puts about 5000 tons of CO2-equivalent emissions
Each launch would then be a 0.00001X, and is approximately equivalent to a trans-pacific plane flight. Thousands of flights per year would not be a significant fraction of the Earth's emissions. Hundreds of thousands of flights would be.
- solar is fine up to around 500X
- which won't happen this century
- when it happens power will be abundant enough that the cost calculations will be radically different
- technology will also be radically different. Maybe we'll use anti-matter reactors or something.
It's difficult to say. We are not running out of land, that's for sure. But we are running out of cheap land. Or rather land where it is economical to build solar. Sahara has plenty of empty land, and it is plenty sunny all year long, but there are civil wars more often than not, various militias, corrupt governments, etc. The US has lots of deserts, but also lots of groups with various agendas that find ways to delay projects, and delays can transform good projects into bad projects.
As a concrete example, take California. California is very proud to be a leader in environmental issues. You can find on the state website the installed capacity per year. For the last 5 years it has been [1], in GW: 1.2 (in 2020), 1.5, 2.0, 2.3, 0.9 (in 2024, so far). The year over year growth rates were 26%, 35%, 10% and for this year -60%. This year is not over, and it's possible the numbers are not up to date, but it's quite unlikely we'll get to match last year's numbers, let alone see a double digit growth.
Or take Texas. Wikipedia has their annual numbers between 2007 and 2023 [2]. I did the math, and between 2007 and 2017 they experienced a 90% annual growth. Nice Moore's law at work there. For the next 4 years the average annual growth was 60%. And for the last 2 years, it was 28%. Nothing to sneeze at, but the trend is clear. Why, if the cost of the panels went down?
> Thousands of flights per year
Elon is not talking about thousands of flights per year. Thousands of flights per day. Millions per year. A million launches of 5 kT CO2e each equal 5 GT CO2 each. That's about 10% of the current worldwide emissions. Or about 30% of the current emissions that come from power generation. If we are to use synthetic fuel instead of fossil fuel, and you have a 30% efficiency of making synfuel (which is what a quick google search indicates), then you have a 2x increase in electricity needs.
You can get to 100% carbon free by using a combination of overprovisioning, source diversity, geographic diversity, storage and statistics. You can't get to 100% but you can get to an arbitrary number of nines and say "good enough". The grid is only 99.99% reliable so having generation be better than that has little value.
If you really want 100% reliability out of a primarily-solar grid you choose something the opposite of nuclear: something cheap to build but expensive to fuel. For example, synthetic natural gas. The cost of the fuel has little relevance when it only has a duty cycle of 0.1%. And they're cheap to build and likely don't even need building because we already have lots of them.
China built a lot of nuclear reactors in the 2010's, but is slowing their build rate. 10GW/year of nuclear power is not very impressive in a country that built 100GW of solar in the first half of 2024.
That being said, I still support restarting TMI. The main costs of nuclear are in building and decomissioning them. We've already incurred the cost of building TMI and we're already on the hook for decomissioning it, so running it is likely cost-effective once you remove the sunk costs.