For the first time in the U.S., renewables generate more power than natural gas

> The problem is that it's occasionally neither and that doesn't have to happen very often to cause a lot of trouble.

The odds of it being neither everywhere (grid) for an extended period of time (storage) is astronomically low. You don't build solar plants and windfarms where prolonged periods of non-production are to be expected.

The once in a century black swan event where distributed power production across a continent all goes down at the same time is basically the same as a blackout from damage to the power grid, which you need to be ready to deal with on those timescales anyways.

We had this conversation a few days ago in the thread about nuclear power. Sorry, I’m not interested in repeating it.

> What you want is dispatchable power.

That's the most expensive one, especially if you both need it to be reliable (can't be a battery that can run out) and need it to not emit CO2 (can't be natural gas peaker plants). So what you want is to minimize the amount of dispatchable power that you need.

Which is what baseload does up to the point that it's generating the "base" (i.e. typical daily minimum) amount of load, because then you don't need any of that portion of the load to be dispatchable since the baseload plants will handle it ~100% of the time.

If baseload is half of peak load then you only need 50% of peak load to be dispatchable because baseload sources handle the other half. If you have no baseload sources then you need enough dispatchable sources to handle 100% of the peak load in case that's the only thing available some days/times, e.g. when peak load is after sunset and solar output is zero.

The difference gets even more significant when you consider the possibility of reducing demand through pricing. Suppose raising the price by a moderate amount can lower the daily average demand by 25%; past that you start hitting inelastic demand and would need unrealistically high prices. If you have baseload as 50% of generation then you now only need dispatchable sources to handle 25% of peak load because the other 25% can be achieved through pricing. Without baseload sources you need 75% -- three times as much instead of twice as much.

More than that, it reduces to 25% the amount of long-term dispatchable power you need, i.e. things that cost a fixed amount to have and are also expensive to use but can't run out of capacity. Things you might only use two weeks out of two years, like hydrogen fuel cells or expensive flow batteries; you don't want to need three times as much of those.

Meanwhile you can use short-term dispatchable power (i.e. normal batteries) to do things like handle the peak demand in the early evening while charging them using solar during the day. The period after sunset but before the load falls off is only a few hours long, so you only need 50% of total capacity for ~15% of the hours in the day, i.e. having only 7.5% of daily capacity would mean that you don't have to use demand suppression through pricing unless you have an extended supply shortfall from renewables. Whereas if you don't have baseload then you need enough batteries for ~50% of daily capacity because now you need enough batteries to handle the entire peak demand in the early evening instead of half and the entire demand late at night instead of none. On top of the long-term storage in case the batteries run out.

Not for industry that needs to run when the sun isn't shining and the wind isn't blowing. Sure, in theory maybe someday battery storage will present another option but that won't be realistic or economically feasible for many years.

> The odds of it being neither everywhere (grid) for an extended period of time (storage) is astronomically low.

The problem isn't that production is literally zero, it's that production is non-trivially below average for an extended period of time.

Continent-spanning grids mitigate that to a certain extent, but they're also a) expensive (purposely-idle high capacity very long distance transmission lines), and b) are essentially a scheme to trade frequent localized shortages for less frequent continent-spanning ones.

Making the grid larger to make it more reliable is also inconsistent with incentives. You install the long-distance transmission line because you're supposed to be using it to get power from far away in an emergency but then it turns out that one end of the transmission line has power which is less expensive, e.g. it gets more sunlight or has more favorable regulations or subsidies. Soon your generation is concentrated in the place where it's cheaper to build and the line gets used to average out long-term prices instead of short-term prices, leaving you with the short-term volatility but now it will affect even more people.

Then you're in more trouble. You get a month of unfavorable weather in the place where generation was concentrated, or an extended period of elevated demand at the same time as total supply is on the low side of average, and instead of a shortfall in Massachusetts you now have one in the Eastern Grid containing everything on the New York side of the Mississippi river.

And the US is one of only a few countries that spans something on the scale of a continent to begin with. Is the UK inclined to be reliant on power from the EU? Is Japan supposed to rely on China? How about India and Pakistan or Israel and any of its neighbors?

> You don't build solar plants and windfarms where prolonged periods of non-production are to be expected.

Prolonged periods of low production happen as a result of weather, e.g. Florida is suitable for solar because it's at a favorable latitude, but it also gets a lot of rain, and sometimes the rain continues for several weeks at a time.

Moreover, suppose there are places that are expected to experience prolonged periods of non-production from solar and wind. What are they supposed to do for power?

> The once in a century black swan event where distributed power production across a continent all goes down at the same time is basically the same as a blackout from damage to the power grid, which you need to be ready to deal with on those timescales anyways.

Having the same weather system affect most of a continent at the same time isn't really that uncommon. You also get nasty correlations like cloudy and still weather in the heart of the summer, causing simultaneous low generation and high electricity demand for air conditioning over wide areas.