Comment by _ph_ | Hacker News Reader

Comment by _ph_ | Hacker News Reader

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Base load is a term from the fossil/nuclear time. It is a pure statistical amount which designated how much "slow" sources (coal, nuclear) could be used because there is never less demand than the base load. And everything was done to push the base load up. But it never meant that it was sufficient to deliver the "base load". The power generation still hat to match any demand at any time. So everything else was done with "fast" and often more expensive plants like gas, water.

In the age of renewables, things have changed. If you have enough renewables to cover large parts of the electricity demand on average, then you will frequently produce 100% more of the maximum grid demand. In this situation, "base load" power plants don't make any sense at all. The new term is "residual load". This refers to the load at a point of time which cannot be delivered by renewables at that time. This can also vary between 0 and 100%. Which obviously requires different power plants, like gas, water.

> This refers to the load at a point of time which cannot be delivered by renewables at that time. This can also vary between 0 and 100%.

If you had a predominantly renewable grid, this would generally be 80-100%, because low generation could coincide with peak load. Which is extremely bad, because then you have to duplicate that proportion of generation capacity via some alternative even though it's only rarely needed. Or worse, it's needed a lot but it's fossil fuels.

Meanwhile you want some degree of energy storage, because if you have times when renewable generation is more than 100% of the load, you want to be able to use that power later and not just throw it away.

But then you're back to base load sources making sense. They reduce the amount of storage or peaker plants you need at night and the amount of renewable generation you need during the day.

They just don't make sense as more of the grid than there is "base load" for the same reason as always. Otherwise you'd have times where there is surplus "base load" generation and have to put that into energy storage, when it'd have been cheaper for that part of generation capacity to be renewables.

Call it what you want you still need an always available always there source of power to ensure demand is met. In the PNW hydro fills this role, elsewhere you will need something else and only nuclear really can fulfil that need

You haven't gotten the point: nuclear is very bad for varying loads and that is why it is bad to fill the gaps in renewable production.

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