[Hnrobert42]

The last section of TFA is called "What happens if the dome is punctured?". The answer: a release of CO2 equal to about 15 transatlantic flights. People have to stand back 70m until it clears.

It would not be good, but it wouldn't be Bhopal. And there are still plenty of factories making pesticides.

[creativeSlumber]

Comparing it to X flights maybe correct from a greenhouse emissions standpoint, but extremely misleading from a safety perspective. A jet emits that co2 spread over tens of thousands of miles. The problem here is it all pooled in one location.

Also that statement of 70 meters seem very off, looking at the size of the building. What leads to suffocation is the inability to remove co2 from your body rather than lack of oxygen, and thus can be life threatening even at 4% concentration. It should impact a much much larger area.

[epgui]

It's a gas in an open space, it diffuses very quickly.

[to11mtm]

Yep. When I had to fill CO2 tanks at a paintball shop yes there were times that I had to open a door (I mean we were talking a lot of fills in short time, btw fills had to start with draining the tank's existing volume so I could zero out the scale) but even indoors a door+fan was enough to keep even the nastiest of sale days OSHA compliant.

Also a 'puncture' is very different from the gasbag mysteriously vanishing from existence; My only other thought is that in cold regions (I saw wisconsin mentioned in the article) CO2 does not diffuse quite as fast and sometimes visibly so...

[ben_w]

https://en.wikipedia.org/wiki/Limnic_eruption

I don't know the safety limits for this quantity, I hope the "70 meters" claim was by someone who modelled it carefully rather than a gut check.

[apparent]

Seems like it would depend if there was a small tear or a massive breach.

[jojobas]

It also deflates pretty slowly. I'd guess any breeze would remove the hazard altogether.

[Animats]

> People have to stand back 70m until it clears.

How did they calculate that evacuation distance? CO2 is heavy. That little house about 15m from the bubble needs to be acquired.

The topography matters. If the installation is in a valley, a dome rip could make air unbreathable, because the CO2 will settle at the bottom. People have been killed by CO2 fire extinguishing systems. It takes a reasonably high concentration, a few percent, but that can happen. They need alarms and handy oxygen masks.

Installations like this probably will be in valleys, because they will be attached to wind farms. The wind turbines go in the high spots and the energy storage goes in the low spots.

[cycomanic]

The distance is likely calculated based on the stored volume and the area you cover until the height is significantly below head height (because as you point out CO2 settles to the bottom). Regarding the little house 15m from the bubble, they are not planning to build this in residential areas, so it's very unlikely that there would be a house within 15m just for operational purposes already.

[Hnrobert42]

Again, from TFA, the install needs 5 hectares of flat land. I thought it was odd when the article mentioned "flat" land, but I assumed it was more about accommodating the bubble. Now I am thinking it is specifically to avoid the valleys you are describing.