Comment by niftich | Hacker News Reader

Comment by niftich | Hacker News Reader

As noted in the article, hydrogen is currently unfortunate, because the most economical way to produce it is through steam reforming of natgas. Germany already has supply issues with natural gas, not just the pressure to reduce greenhouse gas emissions. Electrolysis of water is another method, but requires a lot of electricity. Using it in the short term is highly wasteful, when the source fuels could just be used directly.

Nonetheless, on a longer timescale, hydrogen effectively becomes a roundabout instrument of space-, time- and demand-shifted energy storage, but potentially bulk-conveyable using portions of existing gas pipeline infrastructure. This compares favorably to batteries (which are heavy, solid, contain other commodities, and are non-bulk-conveyable in a comparable way), and other energy storage schemes (which are immobile or lack effective the distribution of work). It's broadly similar to hydrocarbon natgas and syngas, but without the direct release of carbon during actual combustion.

The hope in this effort to encourage progress and deployment of hydrogen-based technologies, infrastructure, and business models, and tolerate some short-term wastefulness to target a more favorable goal in the long term.

Hydrogen is difficult to store, difficult to transport, low-density (it's the lightest element) and a fundamentally inefficient store of energy. Avoiding releasing carbon during combustion doesn't seem like a particularly worthwhile reason to make all these sacrifices. Carbon release isn't, per se, the problem - it's the open-loop carbon cycle from buried fossil fuels.

I have read that the meme that hydrogen is a good replacement for fossil petroleum mostly gained ground in the GW Bush era, in an attempt to appear to be taking green fuels seriously in a way that was actually friendly to petrochemical industry. It's not a coincidence that 1) Bush pushed the "hydrogen economy", and 2) hydrogen largely comes from fossil fuels.

A really, really good writeup here: https://www.thenewatlantis.com/publications/the-hydrogen-hoa...

Can't hydrogen be used as a mean of energy storage? If nuclear power is used, wouldn't that make hydrogen much cheaper and viable?

It's true that it's inefficient, but I'm curious as of how much inefficient it really it, because nuclear energy can be made abundant and cheap if you use electrolysis close to a nuclear plant.

Storing large volumes of hydrogen is very difficult.

Seems like they're storing it in the gas network, does that not scale?

There's enough energy in the gas network today to power the world for a few days, seems like a great way to store excess renewable power.

They are mixing it into the natural gas in low amounts. High concentrations of hydrogen tend to diffuse through and embrittle many structural metals used in gas pipelines.

Salt domes (commonly used to store large amounts of natural gas) might also be useful for hydrogen storage but would need to have their plumbing replaced.

So you'd need a new method of storage, but the scale seems decent enough. Or could you use spare electricity to generate larger molecules?

Not true. Stick them to a carbon-based backbone and they become energy dense and easily-transported liquids at standard pressures and temperatures. The resulting chemicals are able to take advantage of massive existing infrastructure, too.

(This may sound somewhat on-the-nose, but one of the biggest lessons 'hydrogen-gas-is-the-future' hype has to teach is just how useful hydrocarbons are compared to any other method of chemical hydrogen use.)

There is about 9gW of peak nuclear power left in Germany. That is a valuable contribution to keep the CO2-mix in the grid low. Using it for electrolysis would be way less efficient than other forms of storage.

Using nuclear to make hydrogen would be silly, when renewable electricity is much cheaper.

I was talking about storing energy, which is a tough problems for cars. The source of energy doesn't matter.

NO, because you waist so much energy it's insane. Look at gravity energy storage systems. Or countries where they store energy in water (also gravity based).

The best way to store energy is in potential gravity energy. We should build these modules connected to the grid to buffer alot energy. Smart Grid etc.

Electric cars with smart grid implementation into them would also help alot.

Also these buffer hubs can even EARN MONEY. If they buy cheap electricity at daytime from solar, sell it at night for more. It's an actual business case.

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