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Comment by Manuel_D | Hacker News Reader

Sure, there are other options. But they each have their downsides:

* Natural gas supplemented by renewables like solar and wind is cheaper, but it's still emitting carbon (plus fostering dependency on natural gas exporters like Russia).

* Hydroelectricity and geothermal are excellent carbon-free and controllable energy sources. But they are geographically dependent. If you don't have a river flowing through a dam-able valley, or access to a seismic fault line you're not going to be building any of these.

* Renewables plus storage can hypothetically delivery cheaper power. But storage at anywhere near the required capacities remain hypothetical. The few solutions that do seem to deliver good storage costs are geographically limited, like hydroelectric reservoirs.

Nuclear remains the only non-intermittent, geographically independent source of carbon-free energy.

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The reason storage for renewables is still hypothetical has to do with the fact that the storage has not really been required yet because people are still willing to burn stuff.

Also, when you offer nuclear as an option, you need to remember that nuclear can't do the job without storage either - unless you're willing to pay out of your nose for something that sits idle most of the time.

Also, in your incomplete list, you're missing biomass, biogas, thermal-electric storage, thermal storage (in the UK, a lot of the energy required could be stored and used as heat) and grid interconnections.

Thermal and thermal-electric are still not widely deployed. But biomass and biogas are.

> Also, when you offer nuclear as an option, you need to remember that nuclear can't do the job without storage either - unless you're willing to pay out of your nose for something that sits idle most of the time.

The disparity between peak electricity consumption and minimum electricity consumption is not so great as most people make it out to be [1], and base load still accounts for the majority of electricity demand.

Furthermore, nuclear plants can module their electrical output by more aggressively cooling the reactor. Your claim that nuclear requires storage is demonstrably false: France operates a grid over 70% nuclear (over 80% at its peak) without energy storage.

> biomass, biogas, thermal-electric storage, thermal storage

What do you mean by biomass and biogas? Burning wood and capturing methane from landfills has been done, but not on a relevant scale.

Thermal and thermal electric storage remain in the prototyping stage. If they prove to be cheap and scalable then great. But that's still in the world of hypotheticals, it may or may not pan out.

1. https://www.eia.gov/todayinenergy/detail.php?id=42915

Hydro isn't carbon free. It takes a lot of cement to build a hydro dam. Even earth damns need to have their central and powerhouse structures made of cement.

Hydro emits less carbon per unit of electricity than solar [1]. And drastically less than the renewables + natural gas mix that's used in practice to accommodate renewables' intermittency.

1. https://en.wikipedia.org/wiki/Life-cycle_greenhouse_gas_emis...

Although it can be highly disruptive to the local environment. So can most power generation plants, but usually indirectly.

In a 100% renewable economy, where is the carbon emission coming from in PV? PV doesn't make carbon atoms out of nothing. Also, that chart is ROOFTOP solar. Rooftop solar is not what would be used to power a renewable-powered society; it's more of a con to game current utility rate structures.

Hydro will always have a problem with methane emissions.

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