alt Hacker News>Building lots of new nuclear instead of doing the cheaper option of tons of batteries and renewables
This is not the cheaper option.
You need to have batteries that can store power for at least a week to have base load as reliable as nuclear power. There isn't enough battery capacity in the world to do this for a state like California, let alone the whole country.
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naw, we'll just build enough battery to cover the nights and then use gas as emergency backup for any rare wonky weather events. that could easily get us to 90+% clean, which would be absolutely amazing. Constant base load only supply like nukes are economically obsolete. On a modern grid you need a rapid response backup. Which is gas for now, and hopefully we'll come up with something to replace that later.
Even with Danish insulation and weather and tilting the study heavily towards nuclear power by assuming that the nuclear costs are 40% lower than Flamanville 3 and 70% lower than Hinkley Point C while modeling solar as 20% more expensive renewables come out to vastly cheaper when doing system analyses.
https://www.pv-magazine.com/2026/04/17/new-metric-shows-rene...
> You need to have batteries that can store power for at least a week to have base load as reliable as nuclear power.
This is a complete myth, somebody pulled "a week" out of their butt a decade ago, it gets repeated a ton, but it's not based on reality or studies or numbers. This is a consistent problem with online nuclear advocacy: there's no basis for the numbers, nobody calculates anything, and if they bother to do a calculation they only calculate the upper bound and then assert "see look a big number" and say that's a proof of impossibility.
What event requires a week of storage? Nobody can name one! When has there been a week with zero generation? No one can name it! The assumptions that one has to make up in order to make a "week" even sound plausible are in turn themselves so implausible.
> There isn't enough battery capacity in the world to do this for a state like California, let alone the whole country.
Imagining there's a fixed battery capacity is a very short sighted view, it's growing by 10x every year.
So let's take your "week" as the measure, even though it's wrong. If we're at 2-3 TWh of world battery production capacity in 2025, that's 4 days of California demand. By 2031 or 2032, we're going to have 20-30TWh of battery production.