Ugh. I typed this into my smartphone while sitting in someone else's house. Slashdot removed all paragraph formatting and there was no "preview" button. Ugh...

Crystalline silicon solar panels are by far the most common type. They require no rare elements. They are made out of silicon and boron as a dopant. Silicate rock is about 80% of the earth's crust. The amount of boron needed in such a solar cell is about 1 part per 10,000, which is lower than its abundance in undifferentiated crust. At present, silver is used for electrical contacts in solar cells, but it could easily be substituted with aluminum with only a very minor loss of efficiency. Aluminum is approximately 8% of the earth's crust. The supposedly "rare earth" elements are about as common as copper. Except we have been mining copper at about 100x the rate of rare earths, and have been mining copper on a massive scale for more than a century, and we haven't hit peak copper yet and are nowhere near it. Many wind turbines do not use any rare earth elements anyway, but use induction magnets instead. We have enough material to cover the terrestrial surface of the Earth in a miles-deep layer of solar panels, which obviously would be useless because only the top layer could generate electricity. Furthermore, the silicon, boron and aluminum used to make those panels are not being "used up" at any rate. The elements do not disappear after being used, and could be re-mined even if they had not been recycled. There may be temporary shortfalls of some rare earth minerals in the future. It will be accompanied by opening new mines and using obvious substitutes which are only slightly worse.

That may be true for wind turbines, but it's not true for photovoltaic cells. By far the largest energy input for the manufacture of solar cells is electricity. That electricity would increasingly come from other solar cells (and from wind turbines) as the share of coal-fired power in the energy mix declines, albeit gradually.

Wind turbines require large quantities of cement (for their foundations) and steel, and those are produced using gas and coal. However, wind turbines produce at least 20x more energy than was required to construct them over their lifetimes, and the output is electricity (obviously), not thermal energy. Assuming 33% thermal efficiency of the steam turbines in coal power plants, it is clear that we obtain approximately 60x as much electricity by using the coal to build wind turbines than by burning the coal in a pulverized coal power plant.

If you want to increase production by orders of magnitude, as this kind of project would require, you'd have to go for less economic ways of making lithium. And that means orders of magnitude higher costs.

You'd need some kind of quantitative analysis to support that point.

Many mineral resources are distributed according to a "resource pyramid", where there is vastly more resource available at each step down in ore grade. In which case, an order of magnitude increase in production may require only slightly higher monetary costs of extraction.

According to this paper, it is nearly economical at current prices to mine lithium from seawater, as a byproduct of desalination to obtain fresh water. The oceans contain nearly 10 million times as much dissolved lithium as in current terrestrial reserves, as per the paper above. In which case, the "ore grade" of dissolved salts in the ocean would not decline appreciably by our mining of them.

For people talking about the "time wasted stopping to charge", several important points.

I've read that argument several times on this forum. While true, it seems like a minor factor.

Presumably the reason that trucking companies keep their trucks driving all the time (using teams of drivers) is because "time is money", and stopping the truck means paying interest on an asset which is doing nothing. However, that's a fairly minor consideration. Even 4 hours of additional downtime per day (for recharging) would cost less than $30,000 in additional interest over the lifetime of the tesla semi. That's minor compared to the money saved on fuel.

Obviously the thing that matters here is total cost of ownership (TCO). If I do some back-of-the-envelope calculations, it appears that an electric semi is cheaper to operate when diesel costs more than $4/gal. Diesel already costs more than that in many parts of Europe. Here in California, diesel costs about $3/gal, but the price of diesel is heading upwards over time, whereas the price of batteries is heading downwards. (The price of electricity in the US is about the same as it was in 1975 when adjusted for inflation, and has never varied by much: https://www.eia.gov/totalenerg... ).

Another important consideration is that diesel has a very volatile price, and volatility costs money by itself. Large transportation companies buy futures contracts in order to insulate themselves against possible diesel price increases. Not long ago, oil costed more than $100/bbl, and it could return there soon. There are also plausible geopolitical events (such as war in the middle east) which could send oil prices above $120/bbl overnight. As a result, large trucking companies require "insurance" against price increases and spend money on futures contracts for that. If small trucking companies buy diesel trucks but don't buy futures contracts, then they are taking an uncompensated risk.

He also made comments about women being neurotic which some may construe as offensive.

He was fired for remarks made at work. In my opinion, his place of employment is not an avenue for his political opinions. He should have anticipated that his remarks about women (even if made about *most* women, not all) would have been construed as offensive and hurtful. The notion of free speech does not imply that Google must continue paying him despite unprofessional speech, in my opinion.

Ann, did you understand what you just read? I didn't say that sexism was non-existent at companies. I said that making remarks or writing screeds about "bro culture" in the tech field is even more stereotyping and worse than any sexism at companies I have observed.

Your response to that is simply to repeat the inflammatory remarks which were just pointed out to you?

It's astonishing to me that remarks like those are made routinely by feminists. I have heard remarks about "bro culture" many times now. Isn't that a stereotyping remark? Frankly, remarks like those are far more extreme than any stereotyping behavior I have ever seen at any startup, and I've been doing this a long time, as you have.

The idea that Gaeten Dugas was "patient zero" was thoroughly debunked soon after it initially circulated. The idea of "patient zero" sprang up because of a paper in the early 1980s (https://www.ncbi.nlm.nih.gov/pubmed/6608269) which implicated Dugas as patient zero. The paper tried to track down AIDS patients' sexual partners, and it included a graph of who had slept with whom. The graph had Gaeten Dugas at the middle of it, connected to all the other AIDS patients through a series of sexual links. Dugas was labelled as node "0", and the others were labelled "1" or "2", etc, depending on how many degrees they were removed from Dugas. (https://upload.wikimedia.org/wikipedia/commons/thumb/7/74/AIDS_index_case_graph.svg/250px-AIDS_index_case_graph.svg.png).

The paper was mistaken. Although those early AIDS patients were all sexually connected to Dugas by at most a few degrees of separation, that does not imply that they acquired the infection from him. It's known now that HIV has a latency period of more than 8 years in young men before overt illness appears. Most of the early AIDS patients reviewed in that paper had directly or indirectly slept with Dugas only 10.5 months before symptoms started appearing in them, which implies that they had not been infected by him. Those AIDS patients who started getting sick in 1982 probably acquired the infection in the early 1970s, long before the sexual encounters with Dugas outlined in that paper. This has been known for more than 20 years.

The problems with the paper are: 1) a few gay men are highly sexually active and sleep with 100+ partners per year; 2) it takes many years for overt illness to appear; and 3) HIV is not highly infectious. As a result, those early AIDS patients may have had dozens of exposures to the virus over the years before encountering Dugas. Within the gay community there is a smallish subset who are hyper sexually active, and they are all sexually connected to each other, with only a few degrees of separation, at least within a particular city. At that point you're just playing the Kevin Bacon game; you can connect anyone to anyone else, and draw a graph however you like.

I had a college professor who strongly resisted getting a new computer. He had a commodore PET with 8 KB of ram. He would type his handouts into the PET, but it could only hold about 3 pages of text before running out of RAM, so his handouts would end abruptly (sometimes mid sentence) because he had run out of memory while typing. On the PET, you could create longer documents by establishing a new file when you ran out of RAM, but he usually didn't bother. When he printed the document, he only had an 8 pin printer, so it couldn't print the letters 'g' or 'p' properly. It was hard to read because he would use a mimeograph machine to produce copies after printing,

I've lived in the San Francisco area almost my entire life. In the SF area, the vicious cycle works like this:

1. Some progressive people live in an urban area, and they decide that they cannot stand urban areas, urban development, or tall buildings. They protest any construction, relentlessly, for decades. Any time anybody tries to build anything, the result is protests, lawsuits, and so on. This has been going on since about 1980. As a result, there was almost no housing development in this area for 3 decades despite steadily increasing population and prices. Granted, some construction started about 4 years ago, but it's WAY too late and not nearly enough. (Apparently, the same thing is happening in New York. The most preposterous example of this is people who've moved to Manhattan and decided that they can't stand tall buildings in Manhattan because tall buildings cast shadows).

2. When rents increase, those people who prevented housing construction decide to blame Google, blame Yahoo, and so on, not blame themselves. Remarkably, they start protesting the construction of housing again. I live in Oakland (just east of SF) and there have been protests against building new housing on EMPTY LOTS, during a housing shortage of critical proportions. People show up and start chanting "we want development without displacement!", as if displacement was caused by too much housing.

Recently I walked around the area south of market st, and saw that typical rents for a 1 bedroom are $6000-$7000 per month, and it's not a luxury area at all. Oakland is getting bad too, but not that bad yet. As a result, the progressive faction has now erupted into a fit of hysterical rage and they vomit on buses which transport tech workers to work.

No, it works with non-controversial subjects.

Unfortunately, it also works with controversial subjects if the article is obscure enough.

I recently came across a page about a fringe crackpot group which included highly inflated membership estimates (in the millions of members, rather than a more accurate estimate of about 300 members). Since the group was very obscure, the incorrect claim had persisted for years. The only people monitoring the page appeared to be group members.

Fortunately, the tools for automatic jerk identification are improving.

If that were true, you wouldn't be able to post on slashdot.

As one of the people who spends time cleaning up stuff like that, it's seriously annoying.

It was a legitimate experiment to an extremely obscure article, and it had no serious negative consequences.

Promoters of wikipedia frequently claim that the source is highly accurate because inaccuracies are rapidly corrected. If they make claims like that, it's legitimate to test whether the claims are true.

As an experiment, I added a spurious and incorrect fact to an obscure wikipedia article, complete with a reference to a document which did not support the claim. It took years before my edit was noticed and reversed.

This only works with obscure articles. The more obscure the article, the less it's checked. If you try inserting something spurious into the page on Obama it will be reversed in about 5 minutes.

I don't think that's right. I've known a couple of EV owners in CA who claim that the electricity costs are less than half what gasoline costs, per mile. The Chevy Volt uses 10 KwH of battery capacity to travel approximately 40 miles. That's 0.25 KwH/mi, which is $0.0375 per mile with electricity at $0.15 per KwH (in CA). Gasoline is about $4 gal and can take a car about 35 miles, which is $0.1142 per mile, which is ~3x as expensive as the EV.