[lazyguy]

Hydrogen is only useful as 'short term storage' of energy.

So whether or not Hydrogen is useful really boils down to whether or not hydrogen is a superior source of energy storage versus Lithium batteries, compressed air, flywheels or whatever.

> This is the last 10-20% of the electrical power market

It's not the 'last 10-20% of the electrical power market'.

What renewables like solar and wind can't cover, without effective energy storage, is 100% of the power requirements 30-40% of the time.

Solar only works when the sun is shining. Wind mills only work when the wind is blowing at a appropriate speed. Unless you produce a massive excess of energy and then store it somewhere then neither of these two technologies can ever replace traditional power generation.

The best you can can achieve otherwise is to have solar power during the bright hours of the day and then massive number of natural gas turbines to pick up the slack the rest of the time.

Traditional power generation plants are a poor match with renewable because they can't vary their output quick enough to match the wildly variable capacity of solar and wind.

So the important part of the question is whether or not hydrogen is a useful mechanism to store the energy. And so far it has not been.

[pfdietz]

"Hydrogen is only useful as 'short term storage' of energy."

This is exactly backwards. It is only useful for long term storage. For short term storage, other alternatives would more efficient and economically superior.

Hydrogen's advantage is that huge quantities of it can be stored underground, at very low cost. Hydrogen can act as a literal rainy day energy fund, and to smooth over seasonal differences in energy production and use.

[kortex]

My take on energy storage is this: Ultimately, hydrogen is more scalable than almost any other energy storage method, save sodium/air batteries (if we can figure that out) and using electric vehicles as batteries (dependent on consumer behavior to scale).

- lithium has scarcity issues which will only get worse with electric vehicles - liquid batteries likewise require some more rarer elements, corrosive enough to require - underground storage (of air pressure, CO2, etc) requires caverns/mines on site - pumped hydro has even tighter site constraints - biofuel/synfuel is decent for mid-to-long term storage, but slow to generate - flywheel has energy density issues

Hydrogen, your main limits are basically steel for tanks, and some rare metals in catalytic amounts.

There hasn't been enough incentive in energy storage deployment to push the scaling up and costs down. But I think we are closest to an "embarrassingly parallel" deployment of hydrogen as energy storage.

[pfdietz]

Lithium comprises only a very small fraction of the mass of Li-ion batteries. The resource constraints are on other elements, like cobalt, used in the electrodes. Lithium could become much more expensive without greatly affecting the economics of Li-ion batteries.