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mchannon

3,157 karma · joined March 15, 2012

Thanks for asking! I'm a real engineer (Materials, Electrical, Solar, and getting into Chemical) and I'm working on a new project in the IoT space.
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mchannon··on Benzene Exposure Alters Endocrine Activity
Looks like a small dose is about as effective as a massive dose.

What’s the downside of a quack doctor selling benzene-contaminated supplements for fat loss?

I’m sure there’s a huge increase in cancer risk, but wouldn’t this cause a lot of fat loss in a human?

mchannon··on Japanese biomass venture using microorganisms to tackle waste disposal
Yes and no.

When you exercise, are you burning calories? Yes.

Are you literally burning calories, as through combustion the way most people understand it? No.

I guess a way to look at this would be akin to community trash fires that are sub-combustion temperature. Yay, now we don't have to truck it 100km to the incinerator, we can just burn it in the village square.

Composting is really challenging because a number of waste products, from citrus to inorganic or hybrid-inorganic garbage, can ruin the compost process and compost product. If someone leaves a metal nail in the compost pile and someone else later plants potatoes in it, that nail could end up in your mouth after a potato grows around it.

mchannon··on Daniel Ellsberg has died
Perhaps the aforementioned phenomenon is his send-off.
mchannon··on Apply with Me to YC W24 in the Next 100 Days and Build the OnlyFans of Trading
Excellent post, but we know very little about you.

What do you bring to the table as a founder? Can you bring in money, can you sell? Is your pitch to YC all set to go, just need the validation of a tech cofounder on your team?

Your idea, which I can see working, is far less important than your ability to make it happen. Can you sell yourself as a partner to a top dev to build your machine and share it with you?

As to the naysayers, the reasons they say this'll never work are identical to the reason OnlyFans would never work. Except it does work. Well.

mchannon··on The US is getting its first new nuclear reactor in 40 years
"But why don't we pay it off in Canadian dollars and save ourselves some money?"

"Just so you know, if that's a route you want to follow, it's 50,000 American, It would be 70,000, roughly, Canadian dollars."

"How are we going to come up with $120,000?!"

mchannon··on The US is getting its first new nuclear reactor in 40 years
2008 called. It wants its prices back.

A visit to sunelec.com or santansolar.com yields a litany of panels for sale well under $1/W. Half the offerings on Amazon are below $1/W as well.

As such, nowadays you should be paying no more than $10k for a 5kW system.

mchannon··on The US is getting its first new nuclear reactor in 40 years
Now that’s just silly. Lots of things are more expensive than a nuclear reactor.

Grid-tied batteries are now about $300/kWh. Capitalized over 25 years, that adds 3.3 cents to peak (11AM) solar prices, which themselves can go negative at times (duck curve in action), and overall are 3-4 cents per kWh.

Nuclear (new) portends to cost between 7 and 20 cents per kWh according to Wikipedia.

Downvote me if you must, but the numbers are right there. Nuclear may have been the best option for a time, but that time has passed and is not coming back.

mchannon··on The US is getting its first new nuclear reactor in 40 years
Than solar, ok.

Than solar plus batteries, the numbers don't back you up on that (or no longer do).

mchannon··on The US is getting its first new nuclear reactor in 40 years
Watts Bar got approved an eternity ago and just got finished 30ish years late.

Vogtle 3 & 4 got approved recently, though I’m not sure the 40 years number is an apples-to-apples comparison.

The elephant’s foot in the room (see what I did there?) is that nuclear is just not cheap the way it used to be. It takes a lot of steel and a lot of concrete.

The reason we haven’t been building nuclear plants is that other plants, gas, wind, and solar, deliver way more power in way less time, and with a lesser quantum of plant size.

The fossil fuel consumption of a nuclear plant, while certainly less than coal, is still higher than wind or solar.

mchannon··on Direct air capture: our technology to capture CO₂
Too late to edit, but I should qualify this:

They claim 4000 tons per year, I did the math on 4000 tons per day. So ~3-4 acres of PV to power, not 1000 acres.

To completely counteract the 37 billion tons per year produced worldwide, and do it with PV only, assuming desert southwest conditions, would require ~30 million acres of PV. That sounds impossibly high, but is only about the size of the US state of Mississippi. 20% of the land area of Texas, on the El Paso side, would be sufficient to keep pace with the entire world's carbon dioxide emissions.

I remain skeptical that this is the most cost-effective approach, as well as skeptical of its ability to scale, but I apologize for crapping on it at first gloss.

mchannon··on Direct air capture: our technology to capture CO₂
We’ll run out of CO2 through the natural version of this process (weathering) long before the O2 encounters this problem. At that point all the plants die, still with plenty of O2 in the air.

In other words, it’s the carbon content that’s more endangered over the next billion years than the oxygen.

The problem with this technology isn’t side effects like this, it’s prohibitive power requirements.

mchannon··on Direct air capture: our technology to capture CO₂
1000 kWh/ton (found it on google):

166 kW/ton in a sunny place:

1000 square meters/ton in a sunny place:

4 million square meters = ~1000 acres of PV to power. One unit.

Yeah, that’s going to happen. /s “We’re too ashamed of our energy requirements to post them on our page and are well aware they’re dooming this technology until cold fusion comes out” is what I read between the lines on their fluff page.

mchannon··on Direct air capture: our technology to capture CO₂
One reason, and not a very compelling one, is that trees in certain latitudes exacerbate global warming by absorbing more heat than naturally occurring grasses (which tend to be more reflective).

In sum, it’s not better.

mchannon··on Direct air capture: our technology to capture CO₂
Removing ALL the CO2 in the atmosphere would be 1-2% the partial pressure of O2 in the atmosphere (barometric pressure where you live swings more than that). Of all the concerns, this one’s low on the list.
mchannon··on Ozempic drug supresses desire to smoke, drink and more?
Eli Lilly's scientific name for LY3437943 is retatrutide.
mchannon··on After 20 Years as a Prosecutor in Illinois, I Quit
Perhaps a good idea in theory, it'd be horrible in practice.

Enough "horse-trading" goes on as it is (you go easy on client A, I'll offer client B up to you on this other case on a silver platter; that way we both make our numbers and look good).

A better idea would be the appointment of a special "evidence master" who holds and controls all evidence and determines who gets to see what evidence, with a bias toward everybody seeing everything. Right now police turn their evidence over to prosecutors and prosecutors determine what the defense (and public) see. If prosecutors don't want them to have something, they don't get it, and no one's ever going to know. I have real trouble believing any society where prosecutions rely on bluffing and brinksmanship to coerce plea bargains is a fair and just one.

There should be no plea bargains. There should also be no peremptory juror challenges. In all honesty, I think AI would be a great candidate to replace both prosecutors and defense attorneys. The playing field would finally be level for once. Judges too.

mchannon··on Widely used chemical strongly linked to Parkinson’s disease
It’s the reverse. People wanted decaffeinated coffee and the TCE stayed for the ride.
mchannon··on After 20 Years as a Prosecutor in Illinois, I Quit
The trope is that public defenders should be and are funded equivalent to prosecutors’ offices. It’s less untrue in IL than in, say, Louisiana, but it’s still untrue.

Prosecutors suffer a self-serving delusion: they’re born on third base thinking they hit a triple.

mchannon··on After 20 Years as a Prosecutor in Illinois, I Quit
After being railroaded by a dirty prosecutor, I’d like to dispel one trope:

Brandolini’s law, also known as the bullshit asymmetry principle, states that it takes 10x the effort to dispel bullshit as it takes to make it. Therefore, every set of bullshit charges takes a public defender 10x the resources to counteract. Any fair system, every fair system, would have public defenders substantially better funded than prosecutors.

I think I speak for a good number of Cook county residents when I say: Bye Felicia.

mchannon··on Carbon-negative concrete
Calcium hydroxide is an extremely weak base in practice, and wouldn't oxidize carbonaceous materials if your life depended on it.

But I could see it depositing in biochar as Calcium Oxide. A physical mixture, not a chemical reaction, is what I meant.

mchannon··on Carbon-negative concrete
First one's on me, the rest you can pay for, or google:

https://e360.yale.edu/features/the_case_against_ethanol_bad_...

mchannon··on Carbon-negative concrete
Exactly.

But you will find dozens of examples in a google search of people who somehow think they've solved the world's water woes by collecting condensate off a disassembled A/C or dehumidifier, and ignorant uncritical news reporters buying it hook line and sinker. Collected funding, even had a whole embarrassing incident at Cal involving the freshman engineering class a few years ago.

There is definitely a need for clean water out of air, but it's got some subtle limitations: you don't need it when it's already raining, and the further you get from that condition, the less well dehumidifiers work in terms of gallons produced per kwh consumed. Below 50% RH, you're getting bupkis for condensate. Most of that energy is spent cooling off air but not quite cold enough to get it to leave its moisture behind.

Here's an easy thought experiment next time you run across one of these "inventions". If a cubic foot of air at 40% humidity contains .24 mL (sorry for mixed units) of water, give them the benefit of the doubt and say their setup is 100% efficient for pulling every last molecule of water out of air. and it runs on a 28cfm computer case fan. How many gallons per hour would that be? 0.1. The reason these suck is not that they don't work in dry conditions (though they don't), but that they don't move enough air to be useful.

mchannon··on Carbon-negative concrete
The article claims "[t]his calcium carbonate strengthens the biochar" but this runs counter to my understanding and I'd like to see some numbers, particularly versus alkalized biochar that is never exposed to CO2.

How important is binding in compression (which is what concrete is used for)? Not very.

Carbonate doesn't strengthen, it weakens. And if forming carbonate in biochar strengthens versus standard biochar, I would imagine forming oxide in biochar would strengthen even more.

mchannon··on Carbon-negative concrete
Since Elsevier is hiding the meat in that journal article, I can only go off what I read, but it looks identically flawed.

• Compressive strength of normal concrete: 25-50MPa

• Compressive strength of their slag concrete with 2h CO2 added: 12MPa

• Compressive strength of their slag concrete with 24h CO2 added: 24.3MPa

My takeaway:

Using slag instead of cement = good idea.

Using slag OR cement plus CO2 = bad idea.

mchannon··on Carbon-negative concrete
I doubt it's intentional. It's just the modern day equivalent of a perpetual motion machine or a "machine that makes water out of air" (dehumidifier).

This particular subject matter area falls in a blind spot where electrical, chemical, and environmental engineering meet, and nobody gets rich pulling the rug out like I just did.

I write about this in my book Fat Gas. Plenty of modern-day snake oil salesmen out there.

mchannon··on Carbon-negative concrete
Making cement releases carbon dioxide in the conversion of flimsy calcium carbonate to sturdy calcium oxide by roasting it.

Reversing the process by injecting carbon dioxide in curing cement is turning sturdy calcium oxide into flimsy calcium carbonate. Every pound of CO2 you sequester this way necessitates multiple pounds of CO2 released elsewhere to get that oxide to your construction site (production + transportation).

The economics and carbon footprint are similar to corn ethanol- attractive and green if you pay no attention to the total balance.

A corn belt politician I’d expect this from. IEEE should know better.

mchannon··on Elizabeth Holmes loses bid to stay out of prison
While incarcerated, half the people "know a guy". Maybe the prison was "better", or maybe it was just a different mix of pros and cons.

Not only was the advice I received unhelpful, following it actually made my stay longer. My family would have been better off taking the substantial amount of money and setting it on fire.

mchannon··on Elizabeth Holmes loses bid to stay out of prison
Hucksters, almost all of them.

They prey on the desperate. They preyed on my family.

mchannon··on Elizabeth Holmes loses bid to stay out of prison
The Bureau of Prisons will designate where she goes, and unless there's some prevailing medical reason (unlikely), or other reasons involving cooperation, request, security threats, access to particular religious facilities, or a repeat stay, my understanding is they're constrained by statute to pick a reasonable distance from home (that might be only X years from release date though).

The women's FCI in Dublin, California is an easy drive and they (presumably) have her level of security. If she wants to say F California (maybe she did in her PSR) then maybe Bryan TX is her destination. Could also be some random third facility. I don't think if a flight risk to Mexico is a concern that they'd be sending her so close to Mexico, but it may upgrade her security level enough that Dublin's off the table.

It's all time and it all sucks. Her kids will get to see her if their father wants them to, perhaps every weekend.

mchannon··on How ^NOT to Forge a Search Warrant
I encourage you to watch or re-watch the stoning scene in Life of Brian. (https://www.youtube.com/watch?v=bDe9msExUK8 @ 2:50).

"You're just making it worse for yourself!"

"Worse? How could it be worse?"

Terms of service are an interesting thing:

1. They have no force of law behind them.

2. They aren't written by congress and should not be treated as such.

3. A corporation writes them for their own benefit.

4. A corporation changes them for their own benefit.

5. A corporation follows them, or doesn't, for their own benefit.

Any violation of corporate terms of service is, at best, a civil tort, not a criminal offense against these United States. Unless you're me, I suppose.

Further, these aren't terms of service I clicked "Agree" to, and in fact they evolved several times without my having read them, nor needed to have read them.

In retrospect, a steady series of frog boiling changes turned my conduct from allowed to questionable. I say questionable instead of illegal, or even forbidden, because I also had, upon every adjustment, explicit written permission from the company to adjust transactions I had not made. Maybe they didn't intend that with their word choices (they reworded it once without changing the meaning), but that just makes it sharp dealing, not fraud. That was absolutely sharp dealing (not a single other customer lost out on rewards, because of how their system was set up). Sharp dealing also happens to take place when an average consumer signs up for a rewards program, or a protection plan, or this week's sale when the actual price on a sale item is actually higher than last week's. I sharp dealt a sharp dealer. That much is true.

The accounts were actual accounts, predicated on fake information (this is not a minor distinction). The fake information was never read by any human, and fake not as a vehicle to defraud (since no human read them), but to avoid getting confused with other customers (it had been a problem), and to avoid getting junk mail. Is the person in line ahead of you at Kroger or Albertson's a fraudster for doing the same? Even if they have 5,000 rewards accounts? Assuming the worst motives in people might be the most comforting way to be, but it's not always the correct way to be.

Appreciate the legal advice (though I don't advise giving people legal advice), but I'd appreciate your considering how many people advise me to do what is easy (they think) instead of what is right. Ever considered signing something you knew wasn't true? That's what the plea offers were, not true. I had 20+ years staring at me on the other side of this false paper I was asked to sign and I don't think I could've signed it if my life depended on it. There's something deeper and more visceral to a signature than an idle scrawl. It's a door to your soul. Does that make me a more moral person than average? Perhaps not, but better than the treatment I've been getting.

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