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The number I guesstimated for my e-scooter is about 500 miles per dollar of electricity.


The electric shower also seemed pretty optimistic. I live in an area with about 50°F/10°C ground temperature and my 14.4 kW water heater can just keep a relatively efficient shower head flowing at a comfortable temperature.


I had this problem once with a water heater: Get in shower, and things are nice and hot. But the temperature decreased rapidly, and immediately.

It turned out that it had been plumbed backwards.


Heat pump or resistive?


This one is resistive (tiny and cheap to purchase) but will be just an emergency-backup shower once my home renovations are done.

The house is getting a split-system air-to-water heat pump with an indirect tank for domestic hot water, so it should cut that down substantially (the unit maxes out at around 3kW input but likely will run longer to recover/preheat).


Every single ICE car driving down the highway is throwing away enough waste heat to heat a small apartment building on a freezing cold day.


IF the joules of energy in your EV battery came from gas-fired or coal-powered generation, a similar amount (~60%) was simply dumped somewhere else.


I wish we did more e.g. district heating with that waste heat in the US.


That means relatively dirty combustion near where people live. The population density around fossil fuel power plants tends to be pretty low in wealthy countries.

You can't pump hot water the same distance you can transmit electricity on HVDC towers.


I feel like the gist here is that "faster, better, cheaper: pick two" doesn't apply to sub-optimally-spaced bus stops. You really can have all three, at the cost of some political blowback from the people who used to have a shorter walk.


I wonder if part of it is also that mining companies are generally allowed to just leave their tailings in a big pile near the mine rather than have to responsibly dispose of the majority of the ore that has no (or negative) commercial value.


The diabolical case is M5 versus 10-32. About a 4% difference in diameter and about 0.8% difference in thread pitch. Basically indistinguishable with the naked eye and even the "nest the threads in each other" check doesn't help without a pretty long length of threads.



They're obviously not the most affordable things around, but if you have an iPhone and spending ~US$250 on a pair of wireless earbuds won't unduly stress your budget, the transparency mode on AirPods Pro is great for this.


They are great. But… I tried them on a plane. It may have been full sound cancelling rather than transparency, and it works, and goes silent but it’s a weird silence. It sort of feels heavy, or loud.


I think the way this would work is you would have your Canadian friend/owner drive it across and then return via another mode of transport. It's entirely possible you could get away with it pretty much indefinitely (especially in an area where folks are used to seeing Canadian plates), but I could also see someone checking a list of "foreign vehicles that entered the US and never left" at some point and one or both of you having some explaining to do (i.e. being ruled inadmissible).


I had a couple of coworkers who had them. I vaguely remember it being based on a ~$35k value in 1997 dollars, so definitely out of my price range as a new graduate earning only a little more than that in a year.

On top of that I'm pretty sure the unit economics were firmly in the negative, even discounting the R&D costs.

They were pretty remarkable though—I got a chance to drive a pre-production one at a ride-and-drive a year before and was super impressed.


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