Spyke

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Heat pumps can't take the cold? Nordics debunk the myth

Good Lord - $2600 for a whole house system? I think that's what my local (mid-Atlantic US) HVAC shop is getting for a single-room mini-split.

Wait until people find out about ground-source heat pumps and water heater heat pumps. What you get out of those is more consistent year round, too. It's almost like leveraging technology has benefits over just burning carbon and hydrogen to make heat.

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Tesla Cybertruck gets less than 80% of advertised range in YouTuber’s test

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In traffic, the largest reduction of efficiency comes from accelerating and the braking. You use energy to start moving (proportional to m V^2) and then you dump that energy into heat in your brakes to stop. The second comes from idling where you use energy to keep the engine rotating. As others have mentioned, EVs use regenerative braking so a substantial portion of the energy used to slow and stop the car is used to recharge the battery. EVs have no need to keep an engine running so unless you’re running the a/c there are minimal demands on a stopped/idling EV.

On the highway, you have the internal friction in the drivetrain to overcome, the constant deformation of the tires, and - most importantly - wind resistance, which is proportional to cd x rho x V2.

Cd (drag) and rho (air density) are low, but that V (speed) squared means driving at 75mph incurs 25x the energy use as driving at 15 mph. An EV gets no sage harbor here - plowing through a fluid (air) is essentially the same work.

To give you a sense of numbers, my vehicle (F150) gets less than 10mpg the 5 miles to my local pool/gym. The speed limit is 25 mph but there are stop signs every block or two. Lots of braking loss. On back roads with gentle curves and a 45 mph limit I get close to 30 mpg. That’s the sweet spot between overcoming transmission friction and air resistance. On the highway at 60 mph I get 22-23 mpg. At 78-79 mph I get 19 mpg. These are all generally on flat stretches using the 6 min average on my dashboard.

(Sorry for the long post…I’m an engineer and mechanical efficiency and aerodynamics are my happy place)

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60% of subreddits are still dark! Reddit activity down 30%

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True punishment would be active, content rich posters zeroing out their posts and comment history. By doing so, the Google searches - which currently refer a ton of traffic to the site - will start to fade. The body of knowledge- users knowledge, not Reddit’s- is what drives new traffic to the site. I plan to remove my contributions later this month, presuming nothing changes.

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It’s Surprisingly Easy to Live Without an Amazon Prime Subscription

Prime used to mean something. Guaranteed 2 day shipping with no minimum for no extra charge. $5 for next day shipping. Then next day disappeared. Then the 2 day guarantee disappeared. Then delivery times were in the 3-5 day range for most things. Then, in my university town, around the time of students returning to school for terms it would be 1-2 weeks. I’m not paying an ever increasing annual fee for that.

steam

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Valve releases the Steam Deck OLED with up to 1TB storage

One reviewer mentioned disappointment that it's still a full 11.7" long and 2" thick. I realize that some people are not built for that kind of size, but I enjoy the heft and find the ergonomics of the original pleasing. I find that it stands out among smaller equipment and any substantial reduction would limit the versatility and, quite frankly, my overall enjoyment.

world

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Stunning State Department Memo Warns Diplomats: No Gaza 'De-Escalation' Talk

The Administration knows there is no solution to this conflict. It also knows there is no state-side position which is politically expedient.

I’m going to say this as loud as I can. There will be no winners in this conflict. Ever. For anyone, involved or on the sidelines.

This memo is confirmation that the US administration knows there is no solution and doesn’t want anyone to say anything because no matter what they say it will make things worse. This is a tacit admission that there is nothing anyone outside can do. It’s like trying to extinguish a lithium battery fire - the stored energy will continue to be exothermic until it’s expended and any attempt to tamp it down is likely to make things worse.

It’s a shitty position were in, but this isn’t some Hollywood script where you can just write a happy ending. There is no happy ending.

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Waymo issued a recall after two robotaxis crashed into the same pickup truck

The description of an unexpected/(impossible) orientation for an on road obstacle works as an excuse, right up to the point where you realize that the software should, explicitly, not run into anything at all. That’s got to be, like, the first law of (robotic) vehicle piloting.

It was just lucky that it happened twice as, otherwise, Alphabet likely would have shrugged it off as some unimportant, random event.

xkcd

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xkcd #743: Infrastructures

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Well, that and every time you touch a DOC/DOCX file it reformats itself to your local settings, fucking up the entire layout. PDF is a terrible, inefficient, poorly (or at least variably) implemented format which was proprietary for two decades but is now about the best option we have for a document to look the same at the recipient end as the sender and still include text, vector, bitmapped, semi-interactive, and certifiable/traceable contents.