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thebluehawk

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That's a compelling idea. I've seen systems that use essentially solar panels on the roof that heats up a liquid in a loop then goes to a heat exchanger which heats up your water before it goes to the water heater, thus making it so the water heater doesn't have to work as hard.

Could we use the exhaust from your fridge, A/C, furnace, etc. to also heat coolant in a similar system that circulates to your pre-water heater, thus boosting efficiency. Especially if you can dump the exhaust of your fridge outside rather than paying to heat up that air, then cool in down again with your A/C.

The question is if the cost savings would be worth the cost of the system.

I would agree, with the caveat of "all else being equal". There is a danger in ignoring vast socioeconomic divides that can put people at a disadvantage that can make things more difficult for certain demographics.

Orbital mechanics.

The earth is orbiting the sun at 30 kilometers per second. So if we launched something into space, since it started on earth, it would have that speed (similar-ish to throwing a ball from a moving car). So that object would now also be orbiting the sun at 30 km/s. We would need to slow it down that much in order to "fall" into the sun.

Once something was in earth orbit, it would only take about 12 km/s of delta v (change in velocity) to escape the solar system.

More info and math here: https://space.stackexchange.com/questions/3612/calculating-s...

Context is important. Pretty much the entire aerospace industry is terrible at time estimates. SpaceX has accomplished some incredible things, so bashing them for "the whole Mars thing" when they are still hard at work on it seems premature and pithy.

And as far as I'm aware they never promised a 30k car? They promised a 35k car, which you can buy today (you just have to email them or go in person and ask for it, it's not available online)

I think there needs a be a different term.

To me "compost" is a decomposing pile of natural materials. Plants, certain types of food waste, animal waste, etc. that anyone can put in their backyard (or scale up to industrial size) to turn waste into nutrient rich soil.

A very specific industrial process that can break down a very specific type of material in just the right circumstances is so completely different that it seems odd to me to share the same name.

A good example are the helicopters with workers inside that work on high voltage lines while they are charged.

The workers touch the lines to bring themselves (and the whole helicopter) to the same voltage and then get to work. That high of voltage should be fatal, but voltage is relative. They are at the same voltage and there's no path for the electricity to follow.

In a truly ungrounded system, if you touch one of the wires in the system, your body will match the voltage of that wire and nothing "bad" will happen. Only if that voltage has a connection back to the other side of the system will current flow through you, either by touching the other wire or if one of the wires is grounded and you touch the "hot" side.

Do you have sources to back up the claim that these people left because of safety or ethical concerns?

From what I've heard, it's a grueling job working long hours and that people get burned out pretty quickly, which is a different issue from saying there are legal, safety, or ethical concerns.

You made several bold claims. Do you have any proof of any of them? The statistic you provided is useless without context. In the last 8 months there were ~24,000 automobile fatalities in the US. What's important is how Tesla Autopilot compares to that.

Also, do you have any proof that Autopilot is getting worse over time that doesn't rely on anecdotes?

Tesla Model Y 7 years ago

Yes and no.

Anytime a li-ion battery is charging, discharging, or even just sitting there the chemistry is breaking down slowly. Charging at higher speeds, charging at higher temperatures, etc. all speed up that break down.

Supercharging does measurable damage to batteries.

However, I'm calling bullshit on this statement, unless by "measurable" you mean you will maybe lose 1% more battery capacity (which would be maybe 3 miles of range) than someone who coddled their battery. Measurable? Barely. Meaningful? Not really.

My Model S is 5 years old and at 80,000 miles, and I supercharge regularly. My battery has gone from 265 miles to 260, which is inline with what is expected.

This is incorrect. They are closing retail stores, but those are usually not the same as the service centers, even if they share a building. An analogy would be a dealership shuttering their sales department but keeping the service department.

The iPhone wasn't a massive success because there were no other smart phones out there. It was that it was a much more compelling product than what the competitors were making.

The Bolt is the blackberry of EVs. Sure, on paper it checks the "mass market EV" boxes but no one is geeking out in cult-like fashion about Bolts like they do for iPhones and Teslas.

It's annoying that they don't make it more clear that's what they are doing, but the gas saving is a real thing. I used to spent $120 a month on gas, that went to $45 a month of electricity, then I got on a Time of Use plan where electricity is cheaper at night and now my monthly "fuel" cost is $15.

I disagree. I think their policy of reacting to content that is harmful and dangerous is a good idea. It's not like the are censoring them. They are still free to spout whatever nonsense they want, they just won't be monetarily compensated for putting other people's lives at risk.

If someone made a cleaning video that encouraged users to mix bleach and ammonia to make a super cleaning liquid, I don't think anyone would disagree that it's harmful and dangerous.

So they require you to do forced arbitration, then just refuse to act on it (or act very slowly).

From a business stand point, of course they would. Most of these cases will at best require time and money to sort out, and at worse cost them even more money (compensating a driver for damages or lost wages). So why wouldn't they let these get tied up in bureaucracy until the drivers decide it's not worth the effort?

Force arbitration is bullshit and anti-consumer.

As with every manufactured good, certain things are prioritized. Your small commodity laptop battery was likely made to be cheap and light, but not necessarily built to last a long time.

That's like comparing a lawn mower engine and an engine in a car designed to last hundreds of thousands of kilometers. They just weren't designed with the same things in mind.

Tesla especially has done a fantastic job with the chemistry and cooling allowing their batteries to have long life even when they are rapidly charged (which usually wrecks batteries).

I would put it somewhere more secure than wallet/purse, unless you are forgetting your master password daily. I put mine in a place similar to a hidden folder in a filing cabinet. I haven't forgotten my master password yet, but I know that it's there if I need it.