A solution that is inexpensive, scales, is not inconvenient, and fits household demands? What's the catch?

I hope it's as good as it sounds and becomes a thing.

Blocks of cement infused with a form of carbon similar to soot could store enough energy to power whole households. A single 3.5-meter block could hold 10kWh of energy, and power a house for a day, and the technology could be commercialized in a matter of years, the scientists say.

Hope this works out. It would be amazing to see new construction using this in foundations. Built in energy storage.

We have already solved this problem, and concrete blocks is not the way to do it.

Water can do the exact same thing, but it flows through pipes and can be moved by pumps, it doesnt "break", it doesnt require complex moving mechanisms, and it can actually 100% fill a given volume (blocks cannot)

We already do this, right now.

This is the whole "they are trying to re-invent trains again" thing.

It's concrete, not cement. Cement is a component, not the end product.

If you leave a bag of portland cement outside and let the rain cures it then that's a cement block.

And the article mentions both but in contradicting contexts. Is "cement blocks" actually "concrete blocks"? Then later it mentions cement being incorporated into the resulting concrete, so what was the previously mentioned "cement blocks"? Nothing made of cement in the shape of blocks are ever incorporated into concrete. Cement powder is.

Anyway, cool concept. In the mean time, the world also needs to figure out how to make concrete more green, because manufacturing cement releases a lot of greenhouse gases.

Direct link to paper: https://www.pnas.org/doi/10.1073/pnas.2304318120

Not my field but takeaways from a quick glace are that they note that the more energy dense they make it the worse it is at being concrete, and that their 10kwh number needs 45m³ of concrete. That would be 15x15x0.2m or like 55ftx55ftx8in which isn't crazy but it's a pretty decent amount.

I thought this was going to be the thing where they use cheap power to raise big weights and then generate power from gravity lowering them.

Technology Connections over here like: IT'S CALLED A WATER HEATER!

The team worked out that a 45 cubic meter material block of nanocarbon-black-doped concrete would have enough capacity to store about 10kWh of energy, which is reckoned to be the average daily electricity usage for a household, so remote off-grid houses with batteries in the foundations could operate using windmills or solar panels.

That's ~1600ft^3 for those of us unfortunate enough to have an innate sense of freedom units and not logical units; a lot of concrete!

I'm very curious about the longevity and durability of these bricks, and safety considerations. Such a house could potentially, (pun intended,) instantly discharge a lot of electricity into someone who comes in to contact with its foundation. Don't use that masonry drill, it might kill you!

The team worked out that a 45 cubic meter material block of nanocarbon-black-doped concrete would have enough capacity to store about 10kWh of energy

Try to visualise 45 cubic meters for the energy storage for 1 person for 1 day without any heating/cooling

This is really exciting if it works out and gets commercialised widely! One thing I’m not sure I understand is whether this requires entirely new cement, or if somehow the carbon black and capacitors can be mixed into existing cement structures (especially roads)? As mentioned in the article, cement is a high emission product and we already have so much of it in the world.

A single 3.5-meter block could hold 10kWh of energy, and power a house for a day

That's... not a lot of energy; can use it up doing like 2 loads of laundry if you have an electric dryer, or running a central A/C for a few hours. (let alone charging an EV, where you can burn through it in a bit over an hour to add maybe 15% or so)