SatanLifeProTips t1_j26zbna wrote on December 30, 2022 at 2:32 AM

Reply to comment by MagicPeacockSpider in Robotic boats are surveying seabeds at offshore wind farms by ForHidingSquirrels

It’s a materials question. Unless you can pull a lithium astroid in from orbit, there just isn’t enough materials to build high efficiency green energy storage. We will see if these flow batteries scale and they aren’t meant for more than a couple of days of use.

We already HAVE power plants. A lot of them. And owners vested in not shutting them up forever. Converting them to run as backups and just putting a shit ton of tanks out back is easy and fast. One day we’ll figure out something better. But when you need 21 gigawatts quiet cold night it is hard to beat.

And you aren’t getting a ship, train or plane to move on batteries very far. Crossing oceans needs something potent like H2.

MagicPeacockSpider t1_j281v0f wrote on December 30, 2022 at 8:41 AM

Planes are the only transport you listed where it's not feasible and H2 lacks density for that application as well.

Ships have acres of space, trains can absolutely use batteries where lines can't be electrified, they're miles long.

If you want to replace fossil fuels from an energy density point of view you're talking biofuels.

There's a lot of lithium on planet earth and batteries are recyclable so an asteroid isn't necessary.

It's all a moot point until we overbuild renewables supply. As well as overproducing food if we want to use biomass and biofuels.

I'm not saying hydrogen isn't a partial solution, I'm saying it's not a primary solution.

We really need to move forward with battery technology as it is the primary solution.

It really doesn't matter what sunk costs anyone has into fossil fuels we should aim for the most efficient solution to ensure costs are low.

Converting current plants to hydrogen will happen when hydrogen is cheaper than fossil fuels. So we're relying on the price/kW dropping a long way. Hydrogen becoming economically viable relies on other technologies. It's not a stepping stone.

SatanLifeProTips t1_j2a9zlt wrote on December 30, 2022 at 7:53 PM

Airbus seems to think Hydrogen is quite viable in aircraft. But what do aviation engineers know?

https://www.cnn.com/travel/amp/airbus-fuel-cell-engine-rolls-royce-easyjet-engine-c2e-spc-intl/index.html

Liquid H2 stores down pretty small. Not as small as Jet A, but given that it is half the weight of diesel even the most die hard engineer takes interest in a massive weight savings. It does require a rethink of current aircraft configurations but as soon as you start talking electric motors you can move propulsion into all kinds of new places. Blended wing designs are likely. (See the render in the article).

And you don’t need any refrigeration equipment with liquid H2 as long as you have a jet/fuel cell running just boiling off the liquid keeps it plenty cold.