rfrey

41 ms·

571.
by rfrey 5y ago
That was our company thesis, that carbon was systematically underpriced and we wanted to amass a portfolio of carbon credits before that was corrected. But you still need to provide project investors with a competitive ROI if you want to bu
572.
by rfrey 5y ago
Typically 15 years.
573.
by rfrey 5y ago
But the LCOE is a normalized (usually to $/kwh) price that accounts for the amount of energy produced for a given capex, plus the operating costs, plus the cost of capital, plus the lifetime of the plant. It tries to bake that all in.
574.
by rfrey 5y ago
Sure, I understand delta-T, and Carnot haunts my nightmares. My question about fusion isn't about thermodynamic efficiency, but about economics. Our waste heat solutions produced electricity at about 2x the LCOE of a natural gas turbin
575.
by rfrey 5y ago
Exhaust from a gas turbine for a pipeline compression station is around 600C at about 95kg/second. That flow contains about 100MW of heat energy, which can be captured with Organic Rankine Cycle (like steam cycle, but using organic flu
576.
by rfrey 5y ago
Our heat sources were typically in the 500-600C range, with plant exhaust flows containing about 80-150MW of energy. Current tech can convert that with about 20% efficiency. Not at all like conventional electricity plants, the heat is alrea
577.
by rfrey 5y ago
We tried to build in Europe and America as well; the economics are just hard. In the US there was very little market for carbon, which is why I said "even in Canada" since there is a regulated price for carbon here. The plants wer
578.
by rfrey 5y ago
Meta-question about fusion energy -something I don't understand about the movement. I spent a few years as CTO of a company providing heat-to-electricity plants. We financed and built them off high-heat plants like natural gas turbines
579.
by rfrey 5y ago
If that's the case, they should really link those developments/retractions/apologies in the comments of that issue. The way the comments end in that issue is a really bad look, and there's no hint to the reader that th
580.
by rfrey 5y ago
I feel like that quote spoke to a particular time. Nowadays I'd point at premature abstraction as the fount of evil.
581.
by rfrey 5y ago
Your parent said they used to read the forum, not that they ran it.
582.
by rfrey 5y ago
It's not nostalgia. It's an observation that the middle class is shrinking. There used to be lots of jobs that supported families that are now subsistence labour. "Well, you shoulda been a programmer" is not a satisfacto
583.
by rfrey 5y ago
Any perceived hostility may come from your very uncharitable read of the the title. The reference isn't any mom, and there isn't any suggestion that moms can't be programmers or are clueless in any way. The reference is you
584.
by rfrey 5y ago
You don't think that bring physically stronger has any role in this on a historical basis? That it's just due to some vague "masculine nature" that women "subconsciously sense?"
585.
by rfrey 5y ago
... on the weekend.
586.
by rfrey 5y ago
Alternative framing: Solution to someone's problem is to propose a tool one has built that helps fix it.
587.
by rfrey 5y ago
Spoiler: a sharpie mark is about one ten-thousandth of an inch thick (depending on color, because size of the pigments!) An interesting use of this bit of trivia: when machinists are trying to grind a block square, they may measure a slight
588.
by rfrey 5y ago
Yes exactly. I was blown away (ahem) and instantly regretted my life choices, which until that point had not involved microns in any way shape or form. The instrument readout looks like this: https://www.perfectionmachinery.com&#
589.
by rfrey 5y ago
Start with researching the "three plate method" to generate a flat surface. A flat reference plane is the first thing you need to make precision machines. (The second is an accurate way to divide a circle.) But the three plate met
590.
by rfrey 5y ago
I overspoke when I said "constant" - like everything, involute shape is a compromise, in this case (I think) between constant torque and manufacturability. I should have said "the shape is intended to minimize torque transmis
591.
by rfrey 5y ago
> (most expensive sector is metrology) Absolutely. But ohhhh... those instruments. I saw a friend with an electronic gauge put it on one end of a 1' bar of steel. He put the gauge on one end and zeroed it. Then he breathed on the ot
592.
by rfrey 5y ago
Slightly know-it-all, but in fact involute gears do rub against each other - they experience pure rolling motion where they contact at the pitch circle. That's the only point where the circumferential speed of the gears is the same. Th
593.
by rfrey 5y ago
The other appealing (to me) thing about machining is that one simultaneously: (1) is forced to realize that perfection is completely illusory: everything is made of rubber, there's no such thing as an exact dimension (2) gets as close
594.
by rfrey 5y ago
The youtube channel "blondiehacks" is excellent for the machining-curious.
595.
by rfrey 5y ago
Your parent did not say any of the things you say they did.
596.
by rfrey 5y ago
This is stunning. I searched "winemaking" because it's my latest obsession, and turned up dozens of links to high-quality pages I'd never seen despite spending an hour a day for three months cruising Google on the topic.
597.
by rfrey 5y ago
Yeah, somebody should really teach them about scrum. XTreme sawmilling.
598.
by rfrey 5y ago
100%. Commodities are for producers, consumers, and speculators.
599.
by rfrey 5y ago
Most construction lumber is kiln dried in less than five weeks.
600.
by rfrey 5y ago
Maybe they can set up some kind of affiliate program with parents to further increase engagement.

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