I'm hoping the current oil-war will cause people to re-assess fossil fuel use as expense becomes untenable and we start choosing electric vehicles and renewables.. which will just become "normal" and oil can stick around for synthetic chemistry routes.
Agreed, it's a big sovereignty issue. Once a solar panel is installed it keeps working for 20+ years. It doesn't get cut off if there's a political problem that interrupts supply.
When is a heap of sand a heap of sand? The answer isn't in the heap of sand, it's in the observer. LLMs are a VERY heap-like pile of sand, and people are starting to see a mind where one might not yet be. I'm trying out a new word for this phenomenon...
Good enough for me. I created the project because I love terminal, and wanted to make something using Claude (to learn how this tool works, strictly for personal enrichment) that solves a small problem I had with some overlapping cron job management.
Sometimes you have a cron job that takes longer than it should (but inconsistently so), and another cron job that clobbers what that cron job is doing.
A lot of people throw around 5% efficiency for Peltiers, and it's just not true - it depends heavily on the temperature differential and current vs. IMax. You can (with care) drive them >2.0 COP.
This isn't anything like a compressor or heatpump system, but Peltiers get a bad rap... they move heat really well if you're not pushing them to the edge.
I didn’t know this, and it jumps out to me because 10k is pretty much the exact difference between room temperature and wine fridge tenperature - I wonder if this is actually not a horrible application for peltiers?
Found a wine fridge at the thrift store last month, pulled the model number, realized it was basically a Peltier cooler and a fan, and thus likely to be still operational. Powered up just fine, so...
$10 and an hour of deep cleaning later, and now we have a wine cooler in our basement. I don't recall the specs or power consumption offhand, but it does keep my beverage-of-choice a few degrees cooler than ambient. :)
You can get 4 COP with a regular air cooled chiller and up to 7 COP if you add an evaporative cooling tower.
Variable frequency drives have made running pumps and fans a lot more efficient, even residential HVAC equipment is starting to get EC motors or VFD driven A/C motors. I can run my 10,000 BTU (1kW) window unit at 68F for an entire month in the summer and it only costs $50 due to the variable speed fans and compressor pump.
What’s the use case for peltier coolers, wearable cooling?
I'm not sure of the exact reasons but you don't really see vapor-compression heat pumps in the tens- to low-hundreds-of-watts range. So I suspect there are some scaling factors where the reduced size/noise/complexity of a solid-state device starts to be more important than the extra energy that it uses.
I think most of the commercial bed cooling systems are thermoelectric (ChiliPad, Eight Sleep) and they seem to work fine, but by the time you get to the scale of a small fridge or dehumidifiers the products are generally awful.
machining metal parts to tight tolerances when they're only a millimeter wide is awfully expensive.
But making tiny things with lithography is really cheap (in volume).
The middle ground is what one needs for a 10 watt vapor compression pump. And to my knowledge nobody has built a 1 watt pump with lithography - although an array of electrostatic scroll compressors does look like it could work.
Thanks for the link. One of the projects I'll probably never get around to is a thermoelectric-augmented fan coil unit for air-to-water heat pump retrofits. The existing emitters (and crucially the in-wall distribution piping that's expensive to insulate and vapor seal after the fact) would stay just above the dew point, and then the augmented fan coil would work to remove latent heat (humidity) by dropping a bit below the dew point via thermoelectric coolers that reject heat into the return piping.
It's a relatively small delta-T and in most climates a relatively small fraction of the overall cooling load, so it might just barely pencil out.
I've spent an afternoon attempting to compile and run RWKV7 locally.. and I just don't get it. lotta errors in compiling... and it's a lot. Like a lot, a lot... it's walls of versions and sub projects.
Any kind of quickstart guide?
Also found.tried rwkv.cpp, and I can't seem to compile that either.
You can add a little calcium carbonate to these inks to give them a little shine and offset some of the acidity.
The really neat thing about these inks is that they are soluble when made, and you can write on a document, then - as they dry - , the soluble iron tannates that work into the fibers form an Fe3+ tannate, which is insoluble - you aren't writing on the surface, you're dying the fibers. This is why palimpsest can occur when documents where scraped and re-used (so you can read the originals with Xray methods)
Source: I have a battery patent based on iron-gall inks (US10749168B1), and it's fun stuff to play with! (see more @ http://bigattichouse.com )
