Hacker News Reader

Comment by Things4People | Hacker News Reader

It would be great if they could achieve this goal. What options do you see that could be used right away?

I think as of today the most efficient approach is pumped storage hydropower. However that is severely limited by geography

I'm guessing that available fresh water is something of a limiting factor here as well.

We have abundant salt water of course. I imagine that generator turbines don't love salt water very much.

it is the most efficient in terms of energy transfer. I think it is lacking in terms of actual storage capacity. the upfront costs are also extreme.

ideally, every green energy farm would have a gravity well storage system nearby (like pumped storage) for the purposes of keeping discharge steady. Energy would be transferred into and out of this system pretty quickly, and stored in a more cost/size efficient storage option that could act as the true "battery" on dark days / longer periods of energy production downtime

I wonder how difficult this would be to implement for consumers/smaller deployments. Could someone dig an underground pool sized hole for a tank of hot water that can be converted back to electricity?

It is really shocking how big of a tank you need for this.

A good example is the large scale hydropower project in Switzerland where they added 900MW capacity to the grid for storage. They do have a good geography for that.

https://www.reuters.com/business/sustainable-business/switze...

Big batteries.

For some applications you can store heat. For instance you can have an electric heater with a lot of bricks inside an insulator box in your house and move heat out of it convectively with a fan.

> Big batteries

Invest in Lithium mines.

For static applications, wouldn't we be better off with batteries based on Sodium chemistry? Less efficient, but removing the geopolitics from one of the main components feels like a pretty big compensating factor.

Don't forget flow batteries using iron, vanadium and other chemistries, as well as various sorts of molten-salt batteries. For fixed installations we could put up with many inconvenient attributes if it gets the cost down.

Forget geopolitics, if you're installing in your house you want something not known for its explosive capabilities...

Reply on news.ycombinator.com