If you want to decarbonize as fast as possible, it makes sense to focus on rolling out wind/solar/battery as fast as possible for now, but keep developing nuclear technology to cover the last bit where it starts getting especially expensive to replace fossil with renewables without losing reliable power. That's exactly what China appears to be doing. They're not just building a few reactors, they're also the world leaders in developing various GenIV designs, like molten salt reactors.
But 98% renewable doesn't mean you can hit 100% by adding 2% more of something else, it means your something else has to supply ~100% of the power 2% of the time.
If China is aiming for that cost-optimal 90-98% renewables, that means they need to build a lot of coal.
Or you design the majority of loads so they can be turned off for 2% of the time.
Load shedding is a better solution than running peakers for [heated] towel rails.
It's not about lights, it's about electricity always being available. And well, always having power available (for domestic, but also for expensive production facilities that looses money while idle) using renewables is a lot more expensive than generating most of your power with renewables
Increased renewable generation is an important goal, but we need to let the facts guide the path, not the other way around.
That paper uses one renewable source, like only solar, and 2018-19 cost data for storage.
A real grid is made up of a mix of sources, which is why the research lately has focused on system costs.
All those analyses find that renewable grids are far cheaper than if involving new built nuclear power.
Here are two modern papers on the subject:
https://www.csiro.au/-/media/Energy/GenCost-2025-26-Final/Ge...
https://www.sciencedirect.com/science/article/pii/S036054422...
B) the post I am replying to is specifically calling for a 98% solar grid.
https://news.ycombinator.com/item?id=49477559#49481711
There's a big difference between "letting the facts guide the path" and tilting at strawmen built out of straw nobody else even brought into the discussion.
If you'd like to make the point that "cost of panels" can be misleading when supporting components and interconnects begin to take up the lion's share of costs then that sounds like a noble thing to remind folk of, but ideally not as a segway into shilling more fracking which includes untold environmental costs as externalities.
It is already stupidly expensive when running at 100% 24/7. Now try running it only when renewables and storage doesn’t deliver.
This is also true of geothermal, which, like nuclear, is almost all fixed capital cost.
But society would be better off with excess generation. So we either need a system where some are incentivized to spin down, perhaps by being paid a consistent amount regardless or something like that, or we need publicly owned power generation that doesn't care about profit.
The problem is that electricity is fundamentally priced on the margin. Now that we are moving beyond a purely centralized design.
Think about a homeowner or factory with their own renewables and storage.
They fundamentally operate on marginal price by choosing when they use their own system and when they buy from the grid.
If you add state owned reliable power to this mix they will cherry-pick. Their own cheap electricity when it delivers and the states subsidized reliable electricity when it doesn’t.
We can try add all manner of markets, fixed connection costs and what not to this but all it does is introduce strange arbitrage possibilities in the market.
Which is why we have settled on net energy markets and then the lowest possible amount of ancillary markets to shore up any gaps which would cause problems for the larger society.
The only way we don't need nuclear power is if we have some other way of producing the energy we need without dooming the planet, and obviously we do not as we're still burning billions of tons of coal every year. Not to mention gas.
We could have made power generation fully fossil free many decades ago if we actually took climate change seriously. It would have been fine. Sure fossil fuels may have been cheaper, but if you include the damage they're already causing and will cause in the future you could multiply the cost of nuclear by orders of magnitude and it would still come out on top. Plus higher investment would lead to faster improvement in the technology, mass production of components and lower cost etc.
Today, renewables and storage are the cheapest energy sources in human history. They are filling the gap nuclear power never managed to fill.
> China, the world's top producer of solar power, rejected 360 terawatt-hours (TWh) of clean power from January to June, up 49% from the same period a year earlier, according to a report this month by Global Energy Monitor (GEM) and the Center for Research on Energy and Clean Air (CREA).
1 - https://www.reuters.com/business/energy/china-leads-wave-cle...
They’re building a massive amount of nuclear. They’re building a monumental amount of solar+wind.
No, almost every one is above 1GW - divide the net capacity by the number under construction to see the power [1]. They appear to be almost all CAP1400 (1.4GW), Hualong One (1.0GW), or CAP1000 (1.0GW). I see a single Linglong 1 (100MW) under construction. Proposed are all above 1GW.
[1] https://en.wikipedia.org/wiki/Nuclear_power_in_China#Future_...