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by enslavedrobot 1021 days ago
If electricity is very low cost then Hydrogen beats batteries for applications past a certain number of hour of operation. This is because batteries have linked power and energy density. To power a house for a hundred hours you need a battery that can power 100 houses for 1 hour. To power a house for 100 hours you only need a hydrogen tank and a small fuel cell. This is why even Tesla is calling for a 1 trillion dollar hydrogen market in 2050.
2 comments

> To power a house for a hundred hours you need a battery that can power 100 houses for 1 hour.

A battery that is meant to power a single house doesn't need to be able to output enough power for 100 houses.

It's important to not be misleading about that because, usually, the lower the rated output of a battery, the higher the power density can be. Which means cheaper and smaller batteries.

I'm not sure I follow. What battery are you referring to when you say a low power density battery can have a high energy density? A flow cell battery?

I'm talking about existing commodity batteries, like lithium ion batteries.

No one is powering a house with a battery, or hydrogen, for 100 hours.

Neither are an energy source. We will power houses with low cost carbon-free energy: nuclear and renewables.

For renewables, interconnection and load and generation diversity will deal with most intermittency issues.

We then provide additional firming capacity with other technology, including energy storage, that in the case of batteries, is probably operating every day, and for pumped hydro and other long duration storage that’s probably operating every week or two, and then some fuel-based generation that’s probably only operating a few days a year.

Hydrogen is probably not a big part of the future power system.

I think if you run the numbers microgrids and cheap storage wins vs major grid upgrades and vast transmission networks.

The grid is going extinct when renewables and storage reach their terminal scaled costs.

As Tony Seba so eloquently put it: "you could capture god and force him to generate limitless power forever at the center of a power plant and it would still not be cheaper than decentralized renewables and storage".