[leonidasrup]

You mean solar + batteries. Batteries can be used to flatten the day/night cycle of a solar power plant on many days. But it's depending on location and it's not cheap.

For cost of $100 / MWh, you can do it in sunny regions like Spain, Mexico, middle East.

https://www.carbonbrief.org/guest-post-how-solar-panels-and-...

It doesn't make economic sense to combine batteries with wind, because periods of low wind output can be multiple weeks long. The betterie costs would be ridiculous.

How do you cover the last 10-20% of the missing solar+wind+batteries output, at what cost?

Usually its a combo of solar+wind+batteries+fosil , costs depend gas cost and CO2 costs.

[dv_dt]

Five years ago, skeptics were saying a few hours of grid on battery was "impossible" and coal would be displaced only by gas. Now we're talking days of grid supply from batteries even from non-grid optimal lithium tech. Batteries are following the manufacturing optimization S-curve and its not even on the fastest part of the curve yet. Lithium is dominant only because its early in the pipe but multiple types of other battery techs (flow, iron+ etc) will probably become viable unlocking weeks -> months -> seasons of output. And probably this will happen before the first nuclear plant from this Iran adventure energy squeeze is even ready to light up - as its taking the west 20+ years to plan and commission a nuclear plant.

[leonidasrup]

It took decades to develop, comercialize lithium batteries, starting in 1970s. Only after 2016 we started to see a large growth.

https://en.wikipedia.org/wiki/History_of_the_lithium-ion_bat...

Cheap gas has displaced lot of coal in US, staring from 2007, fracking gas revolution. In China not much.

https://ourworldindata.org/grapher/share-energy-source-sub?t...

Currently, the Iran energy squeeze is not much felt in the west, just slight increase in prices. It would take real pain, something like 1973 oil crisis, for west to reconsider nuclear power generation.

[gpm]

> How do you cover the last 10-20% of the missing solar+wind+batteries output, at what cost?

First of all, we're very far from this being a problem. If you "only" move 90% of the electrical grid to solar and use fossil fuels to make up the remaining 10% it's a ridiculously huge win anyways. The person you are talking to is just talking about "new power", not "replacing all existing power"... so unless the grid is growing by 5 to 10x your objection here is utterly irrelevant.

Secondly, that whitepaper shows you can do this with incredibly unfavourable assumptions. Namely that they're

1. Ignoring transmission, in reality we can and will move power around from sunny to shady areas. The paper is assuming a single off grid facility. Because different areas are cloudy at different times this greatly reduces the peak amount of batteries needed.

2. Ignoring other sources of energy, like wind, hydro, etc. Because their failures are uncorrelated with solars failures, they greatly reduce the amount of storage needed to hit reliability targets. It's a lot more likely that you'll have a cloudy week than a cloudy and windless week.

This is also why pairing wind with batteries makes a ton of sense. You aren't just pairing wind with batteries, you're pairing wind with a mix of other electricity and batteries. The more uncorrelated sources of electricity you have the less batteries you need to paper over outages.