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.
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.
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)
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.