a conversation with a friend about whether they could run an air conditioner off of an affordable amount of solar; yesterday's experiment in running the desktop computer off a battery pack while the power was out:

good reminders of the (massive) gulf between power consumption norms enabled by the grid and any practical alternative for most users.

@brennen Unless you have something convenient to sink the heat into (body of water?), space cooling is probably always going to be a very energy-intensive process. There's only so much you can do with practical insulation. Thermodynamics is a bastard.

I do wonder if we're going to see developments in "cool the person not the room" as temperatures in some densely-populated areas rise.

@brennen Just for S&Gs, I looked into air-water heat pumps. Turns out that despite being for boats, they are not as stupidly expensive as most boat-related things are.

For ~$2200 you can get a 16k BTU/hr, 120V unit with—if my napkin-scratch calculations are correct—better efficiency than an "ultra HE" (21 SEER) mini-split. And no outdoor compressor or refrigerant lines.

You'd just have the *slight* issue of needing 400 GPH of <95F water. Maybe a big in-ground pool?

@kadin heh, this is an interesting tack, but the friend in question was talking about _portable_ (dry land) setups, so probably a bit of a nonstarter.

i think we have successfully nudged them in the direction of building a foam hexayurt for the most extreme use case they're currently contemplating, and reconciling themselves to a generator when absolutely necessary (they deal with some health issues that make active cooling a must at times).

@brennen Yeah, unfortunately lots of the places where you need cooling don't have a ton of water to spare either… I just fell down an internet rabbithole and was sorta surprised that a device like that wasn't much more expensive.

If ever I find myself in possession of a pool, I'll have to remember that they exist…

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