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Comment by wazoox | Hacker News Reader

To be a somewhat believable alternative to nuclear, you'll also need tons of batteries. Many, many tons of them, full of lithium and cobalt and other things. Because a solar plant produces power along a very steep bell curve centered around noon, while a nuclear plant produces linearly exactly the amount you're asking for 80 to 95% of the time.

This is only alluded to in the article, but intermittency is a major nuisance and hinders significantly actual utility of renewable power, because we need a base level of production they're totally incapable to provide unless backed with literal mountains of storage (storage technology at scale we don't know how to build or manage today).

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while a nuclear plant produces linearly exactly the amount you're asking for 80 to 95% of the time.

Only if it serves as baseload. In other cases you have to throttle it, which quickly makes the whole business much more expensive per kWh.

And this is the reason nuclear will never be the solution. Overprovisioned renewables combined with gas peaker plants are simply way cheaper and much faster to deploy.

Also batteries needen't be li-ion. Here's an example of a company that is currently in the process of scaling up their battery product:

https://eosenergystorage.com/

>Only if it serves as baseload.

...which is the whole point of nuclear. It's constant power.

The means to manufacture, service and maintain battery capacity sufficient to meet our civilization's energy needs from renewables simply does not exist in any technology, period.

But demand is not constant. You either have unmatched supply/demand or expensive power.

For this reason nuclear is already losing on the economical front.

As for the batteries: citation needed.

Renewables are extremely cheap only because they produce power when it isn't needed and therefore is literally worth nothing.

As for batteries, the biggest batteries in service now are 150MWh. If we want to power the world with renewable, we'll need TWh of batteries. We just don't know how to build something like that. We haven't got the technology (lithium isn't an option at these scales).

Renewables have an effect only as long as you have a steerable baseload of coal, gas or nuclear to actually feed the demand. They have a positive effect only as long as you haven't phased out all of your coal. As long as there is no coal burner left, they'll set a high limit on emissions. Unless, of course, we build as many nuclear plants as possible in the meanwhile instead of masses of gas firing plants (400g/CO2/KWh).

We could build batteries and much more solar and wind power plant instead, but even if we suppose a non-existent cheap battery technology, providing large scale power this way would be tremendously expensive (5 to 30 times more expensive than nuclear, depending upon the hypotheses).

Solar has an actual output of 15% its theoretical power. Wind is about 30% (onshore) to 40% (offshore). So to produce x GW of power, first you'll need x * 3 to x * 6 GW of installed capacity; second you'll need additional capacity and batteries to offset times of no wind or no sun. Figuring the price of several hundred GWh of battery storage is left as an exercise to the reader, but it can't be cheap. Plus the grid enhancements needed to transport the additional peak capacity from power plants to batteries, etc.

We need zero-emission power. Renewable+gas is a 300g/KWh CO2 affair. This isn't a solution at all. Nuclear is 12g/KWh CO2.

Nuclear is an expensive and slow to deploy 12g/kWh, so unlikely to match incrementally added renewables by sheer opportunity cost alone.

We need to reduce CO2 today. Your average nuclear plant takes 7.5 years to complete.

I don't think that in current circumstances the cost of reducing emissions is lower for nuclear.

In France 75% of our electricity is produced with nuclear power, and we're able to dynamically change its power to follow demand (though we also use hydro power plants to deal with shorter term variations). And we have one of the cheapet electricity in Europe.

Unfortunately that is changing, because governments want to reduce the share of nuclear down to 50%. But that's a political choice and not a technical limitation.

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