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Archive for the ‘Uncategorized’ Category

Links for October 2023

Monday, October 2nd, 2023

Exclusive: John Kelly goes on the record to confirm several disturbing stories about Trump

Hair Turns Gray Due to Stuck Stem Cells: Hair-coloring stem cells must swing back and forth between their maturity states to give hair its color. Sun et al., 2023

Unvaccinated more likely to have heart attack, stroke after COVID, study finds. Being fully vaccinated reduced the risk by about 41 percent.Jiang et al, 2023

Are the costs of Brexit big or small? by John Springford
“the British economy is around 5 per cent smaller due to Brexit”

The Overwhelming Case for CBDCs (central bank digital currencies) by Willem H. Buiter

Scarce Labor As The Cause Of Innovation. The Habakkuk thesis, Rome and the robotics revolution by Angela Nagl

Book: Ignition!: An informal history of liquid rocket propellants. by John D. Clark

The Tacit Knowledge Series

Why can’t our tech billionaires learn anything new? On Marc Andreessen’s “techno-optimist manifesto” by Dave Karpf

Links for September 2023

Saturday, September 16th, 2023

The Trilateral Shitpost Fire that was the 1980 GOP convention, part 1: On the long history of thinly veiled antisemitic conspiracy theories on the GOP’s right edge by Seth Cotlar

An Exciting New Approach to Autoimmune Diseases by Eric Topol

Absent Gods, Absent Catastrophes : The Sharing Knife and The Lord of the Rings

Disaster Conservatism: There’s nothing worth saving from the Tory years. Nothing at allby Nick Cohen

Links for March 2023

Monday, March 6th, 2023

The Bluestocking, vol 259: Dahl and Fleming

Two Stories About Tacit Knowledge To build a nuke or (can) not build a nuke by Rohit.Krishnan

Book: The Gutenberg Parenthesis The Age of Print and Its Lessons for the Age of the Internet by Jeff Jarvis (2023)
“The Gutenberg Parenthesis traces the epoch of print from its fateful beginnings to our digital present – and draws out lessons for the age to come.”

Book: Glass Art From the Kiln by Rene Culler (2010)

Marx generator This circuit generates a high-voltage pulse by charging a number of capacitors in parallel with DC, then suddenly connecting them in series.

Perimeter of an Ellipse. Estimate or infinite series.

2014-2015 Flint water lead

Monday, March 6th, 2023

This article by Kevin Drum argues that the Flint water lead poisoning episode was not that bad, there was little lasting damage, and the biggest issue today is people hyping the issue and scaring kids (link).

I have to disagree that “…little damage done. Lead levels never got all that high”. True, the attention the problem received led to a quick response that soon fixed the water, and the lead levels in children’s blood began to decline.

But when the lead issue was discovered, “Resident Zero”’s water had lead levels of 217–13,200 μg/L, 14X – 900X alarming levels (!

In the initial study, in 7 of the 9 Flint wards, > 20% of households had water lead levels > 15 ppb, the action level. In the worst wards, child blood lead levels were elevated in 11%, 9%, and 6% of children ( In a quick search, I don’t see how high blood lead levels rose in these kids.

There were 17 months between the water switch and the start of corrective measures. The water lead issue was first identified in Feb 2015, and testing over the spring and summer raised greater and greater alarm as it became clear this was a widespread water issue, and then in Oct 2015 corrective measures were taken.

Several thousand children <6 years old (of 9,000 in Flint) had significantly elevated blood lead levels for more than a year due to this poisoning.

COVID-19 origins, again

Saturday, March 4th, 2023

With an announcement by the DOE, that they sorta think COVID-19 leaked from a lab, the discussion is back on. But there is no new evidence, just a mention of ‘intel’.

I am not an intelligence professional, but I have a few related
questions. US intel on this could come from phone intercepts, emails
collected in real time or hacked out more recently, or from chatting
up Chinese virologists at conferences, etc., but this will give the US
at best a more limited view than the Chinese govt has. No doubt there
were calls, emails, reports issued, panic and alarm as China became
aware of the outbreak and tried to contain it. But how likely is it
that the Chinese govt or scientific officials knew the origins of
COVID-19 early on, or worked it out later on? If Chinese officials
don’t know, an effective intelligence operation can’t extract an

How could China know? If one or more people at the Wuhan Institute of
Virology came down with COVID-19, passed it on to family and
acquaintances, and then COVID-19 spread more widely, they could track
these connections. Classic gumshoe epidemiology. But that did not

Chinese doctors only became aware of a new disease in Dec 2019, health
officials jumped in by the end of Dec, and samples were collected from
Jan 2019 – March 2020 in the Wuhan market. These samples and those
from early cases in the region have all been sequenced, published, and
shared. This was close to the origin of the pandemic, and it is
unlikely China has any better information on what happened than the
rest of us have. COVID-19 passing into humans much earlier and only
becoming pandemic in 2019 is ruled out by the analysis of COVID-19

The best guess at the origin of COVID-19 remains a couple of papers looking at the evidence, the epidemiological evidence of when and where early cases arose, and how it was transmitted, and the genomic evidence from sequencing of COVID-19 in early patients, and comparing these to each other to make a tree of early -> later virus genomes, and to see how the early viral genomes in human patients differ from wild relatives and samples found in the Wuhan live animal market. This sort of analysis can also provide estimates of time–how long the virus has been circulating in human hosts. (ref1, ref2, ref3).

Stupidest things in Movies (part 2 of an ongoing series)

Saturday, January 14th, 2023

In the Marvel movie, where Thanos snaps half the universe to dust. Incredibly, inexcusably stupid. Let’s take Earth as representative, the population doubles in ~50 years. So Thanos worked for decades, centuries (longer?), with heroic effort, developed an army that destroyed planets, and his big effort bought the universe 50 years?! Do these people not know basic math? Can’t think at all about population dynamics?

If Thanos had dusted 99% of people, it would have bought the universe 400 years. If he dusted 99.999% of people, he would have bought the universe 1000 years, maybe more if too few people survived to keep tech civilization humming along. So it’s all marginal, hardly changes anything.

So maybe Thanos doesn’t dust people, he dusts entire civilizations. If Thanos destroys 99.999% of civilizations, they again bounce back in 1000 years, but takes potentially more time to spread from planet to planet, say 100,000 years. Not nothing, but not that many years, 1 part in 100,000 of the age of the universe.

Thanos really needs to give his ‘less crowded universe’ plan more thought than the two seconds the scriptwriters / comic writer gave this.

Green energy and nuclear power

Saturday, January 14th, 2023

In discussions of wind and solar power, sensible centrists always pop up with, “We must build new nuclear power plants too!”. And then mumble on about how nuclear power isn’t really dangerous, especially new designs, and talk about how nuclear power provides steady base load power which is necessary because wind and solar are intermittent.

For example, see this Freakonomics Radio podcast hosted by Stephen Dubner, which is noteworthy for never meationing the cost or relative cost of nuclear power. No economics in Freakonomics! And in a more reasonable discussion between host Ezra Klein and Jesse Jenkins covering a host of energy / decarbonization topics, nuclear power is boosted as a necessary component, again without a discussion of costs.

But this idea that nuclear power is necessary and complementary is mostly nonsense. Yes, nuclear power has killed very few people, and compares favorably in overall safety to coal power plants which cause plenty of deaths due to air pollution. But this argument is almost entirely off target.

The intermittency of wind and solar power is a big issue. Working out solutions for providing steady power in a grid powered mostly by wind and solar is the challenge for the next generation or two.

The thing is, nuclear power doesn’t help with that. Nuclear power plants are run full out except for maintenance (a capacity factor of 92%). What’s needed to complement solar and wind are power sources that are dispatchable and can be ramped up and down quickly. Hydroelectric power provides that in places like the US’s northwest that have lots of dams. And today gas peaker plants and coal plants provide fast and slow power that can be ramped up and down as needed.

And nuclear power is expensive, very, very, expensive. Today nuclear power costs 3-4X as much as solar and wind power. And that is market cost, excluding the subsidies provided by the federal government for nuclear power. Nuclear plants are insured by the US government. The costs of a meltdown are immense, from billions to hundreds of billions, and with a chance of a nuclear plant disaster of at least 1 in 165 over the life of a plant, the risk is substantial. Long term high level nuclear waste disposal has not been paid for or figured into costs–US nuclear plants store high level waste on site, along rivers and coasts, with the US government expected to handle final storage. And nuclear plant decommissioning will likely cost more than the collected funds account for.

So nuclear plants don’t make economic sense on their own and they do not complement wind and solar power generation.

What is needed to make a power grid with wind and solar the primary power sources able to provide reliable power? There needs to be ways of meeting short term (minute to minute), medium term (hourly and daily), and long term (days and weeks) interruptions in wind and solar power production. Short term irregularity can be met today with small grid storage and hydropower.

Dealing with the daily cycle of solar power production requires much larger grid storage, generally not available today, and/or large scale demand shifting not done today. Short periods of low wind are fairly common, and week- or month-long regional low wind is known to occur. Solar power production is lower on cloudy days, and varies seasonally.

It is not clear today what solutions will be used. Grid scale power storage is an active and promising R&D area. Over-capacity–having more solar and wind capacity than is needed will help, and solar and wind are already cheap enough for it to be economic, but this creates a new problem–what to do with the excess power generated during high periods.

Demand-shifting has a lot of promise, and will help with hourly and daily power demand balancing. Residential and industrial power use modulated by utilities is already in widespread use, mainly used to shave off peak demand and do modest demand shifting today, but there is much more potential, especially as electricity gets used more widely for heating water, cars, and homes.

For long periods with low wind and solar power production, other strategies are needed. Today, fossil fuel plants are used. Grid interconnects able to transfer substantial power between regions can be part of the solution–areas with low wind and heavy cloud cover are typically regional. Long-term, there is also potential for storage of energy in other forms–compressed air, hydrogen, or hydrocarbons. A round trip efficiency of ~25% is enough to make this practical.

So there are challenges to powering the grid mainly with wind and solar power, but nuclear power doesn’t help with solve them. If nuclear power with lower, competitive costs can be developed, then it is safe enough to use.

Energy and green energy

Wednesday, January 11th, 2023

Several times I’ve run into the argument that renewable energy can’t supply enough energy, because it will take too much land and other resources to build. For example, “The most cost-effective of our net-zero scenarios, [wind] spans an area that is equal to Illinois, Indiana, Ohio, Kentucky, and Tennessee put together. And the solar farms are an area the size of Connecticut, Rhode Island, and Massachusetts.” link.

That sounds off, so let’s check it out. The US has a total energy production capacity of 1.2 TW (2022). The US used about 4,000 billion kilowatt-hours (kWh) in 2022 (link). That works out to 38% utilization of the power generation capacity. Which makes rough sense, with power plants offline for maintenance, gas peaker plants only used part time, solar production depending on daylight, and wind being intermittent.

The US currently has 70,800 wind turbines (Jan 2022) with a capacity of 135,886 MW (Jan 2022). And the US has 120,503 MW of installed solar panels (2021). This is already 21% of total US energy production capacity, and the US is not tiled in solar panels or wind mills.

Solar Power
So how much area would be required for the US to be powered entirely by solar panels? Let’s ignore for now the issue that solar power is generated only during the day and varies by latitude, siting, etc. Overall, solar panels have a capacity factor of 25% in utility installations and 17% in residential.

Solar panels are rated at 200W / m2, so a capacity of 1.2 TW requires 6e9 m2 of solar panels. With 1e6 m2 per square kilometer, that works out to 6,000 km2. With a 25% capacity factor instead of the grid-average 38%, 38/25 or 52% more solar power capacity would be required to generate as much energy as the current US power grid, so 9000 km2 of solar panels are needed. The continental US has a area of 8.5 million km2, so about 0.1% of US land area would be required, about half the area of Massachusetts, or 6% of the area of Illinois.

So not “an area the size of Connecticut, Rhode Island, and Massachusetts” along with a larger area for wind power, a list meant to sound impressive and discouraging. But the listed states are tiny, with a combined area of 35,000 km2. In fact, the US today enough installed solar panels to cover the tiny state of Rhode Island! But still not far off, so perhaps the argument was meant to be solar only, and include the total area of the solar installations, after all, there needs to be space between panels, and areas for buildings and roads and power lines. Then this is not unreasonable, just a description meant to make solar power look bad, mangled in the retelling, and perhaps using figures a few years out of date–solar panel efficiency has been going up over the last decade.

Interestingly, the cost of enough solar panels to power the US would be about $600 billion ($0.33/W), or $4 trillion ($2.25/W) for complete solar installations. The US currently spends $400 billion / year on electricity.

Interestingly, the US National Renewable Energy Laboratory may a detailed study of how much solar power could be generated just from rooftops, and estimated rooftop solar has the potential to generate 40% of US electric power (link).

Wind power
Wind mills have a higher power capacity than solar panels, “Capacity factor of land based wind in the U.S. ranges from 24% to 56% and averages of 36%.” (link). And while intermittent, on average wind mills produce more power at night than during the day, and more in winter than summer months. So they provide a good complement to solar power.

Let’s do some estimates using wind mills of a typical size, 3 MW. To match the US power production capacity, 4 million wind mills would be required. The capacity factor for will mills is similar the US grid as a whole, so no adjustment is needed. Wind mills need to be spaced out so they don’t block each other’s wind. Minimal spacing (link) works out to one per acre or 250 per km2. So 4 million wind mills will require 16,000 km2. Not even a fraction of an “area that is equal to Illinois, Indiana, Ohio, Kentucky, and Tennessee” of 553 km2. Which is 3/4 the area of Massachusetts, or 11% of the area of Illinois. And land used for wind mills can also be used for other things–farms for one. The ground footprint of wind mills is only a fraction of their spacing.

The US grid already includes 6.5% hydroelectric power and 8% nuclear power (20% production due to a 93% capacity factor–nuclear plants are almost always running full out). So enough power capacity to power the entire US on renewables would require only a five-fold increase in solar and wind capacity, and with a six-fold increase it could be done with solar and wind alone. This seems eminently doable.

Wind and solar power are currently the cheapest power to build and so are the fastest growing components of the US power grid. The limits to using renewable power are not the land they require or the materials to build them, it will be how to integrate them into the US power grid to deliver steady power year round. Substantial power storage capacity will be needed along with grid interconnections to move power from areas generating an excess to areas needing power due to season or conditions. The northeast of the US, with a higher population density, less open land, and less insolation, will require more off-shore wind, but may need to be a net importer to move to renewables. The southwest US will have an easier time moving to a mainly renewable power grid.

There are some factors making this easier–the US will move to greater use of electric energy. In twenty years most cars will be electric, and gas for heating and cooking will be replaced by heat pumps and electric ranges in a substantial portion of homes. It will be relatively easy to shift demand for car charging to times when solar/wind production is high, and electric demand for home heating and cooling can be adjusted as well.

The Solar roof

Sunday, December 18th, 2022

David Brin, in a comment on his blog describes Elon Musk as a ‘successful innovator’ rather than an investor or government subsidy truffle pig. Brin seems to be under the impression that Solar City “put up 2 million solar roofs”.

As best I can find, Tesla has only installed a few thousand ‘Solar Roofs’. Electrek reported in 2022 that Tesla was doing 23 installs / week, and was pausing installations. Tesla started mass market deployments of the product in 2020.

Tesla bought SolarCity in 2016. SolarCity does mainly ordinary solar panel installations, and Tesla uses combined figures to make it seem like the ‘Solar Roof’ product is more successful. The Tesla ‘Solar Roof’ costs several times more per watt that ordinary solar panels, and doesn’t make economic sense.

Check Mac MDM status

Friday, December 9th, 2022

profiles status -type enrollment