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bryanlarsenyesterday at 5:20 PM3 repliesview on HN

The most cost efficient new-build grid is 90-98% solar/wind/battery depending on your locales insolation & wind coverage. (Source Ember Energy) The remaining 2-10% is nat gas, if you have a piped source, or coal if you don't.

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.


Replies

robocatyesterday at 10:30 PM

> supply ~100% of the power 2% of the time

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.

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fpolingyesterday at 6:52 PM

And they build a lot of modern coal power station with over 45% efficiency and flexibility in power output.

idiotsecantyesterday at 8:12 PM

Solar battery is not by any stretch of any possible definition the cheapest generation to deploy. Not even close. We do a disservice to the entire conversation saying easily falsifiable things like that. At 90% penetration solar + battery has a LFSCOE somewhere around $800/mwh depending on the study. Natural gas is something like 30-60. Solar panels are cheap. Building the required transmission and storage to service those panels is far more expensive than the panels themselves.

Increased renewable generation is an important goal, but we need to let the facts guide the path, not the other way around.

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