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Bill Gates Is Beginning To Dream the Thorium Dream
Daniel_Stuckey writes "TerraPower, the Gates-chaired nuclear power company, has garnered the most attention for pursuing traveling wave reactor tech, which runs entirely on spent uranium and would rarely need to be refueled. But Terrapower just quietly announced that it's going to start seriously exploring thorium power, too."
The Gates connection is an idiotic myth.
No, the connection is wrong only as far he didn't literally say "ought to be enough for everyone".
That the correct quote:
I have to say that in 1981, making those decisions, I felt like I was providing enough freedom for 10 years. That is, a move from 64k to 640k felt like something that would last a great deal of time. Well, it didn't - it took about only 6 years before people started to see that as a real problem.
yup, he admit that he had a part in designing the 640k limitation and admits that he though at the beginning that it shouldn't be problematic, but the realised the error later.
Yes it was due to the design of the original PC, which used 640k for RAM and the rest for video & BIOS.
The 8088/8086 processor used in there machine has no such limitation. (Hint: 640k isn't a power of two, so very likely, it isn't a bus limitation. The bus is 20bits, meaning that it can address spaces up to 1MB).
The 640k is purely an arbitrary choice. You have to put the non RAM parts (ROM, Video ram, etc.) somewhere in the address space.
The most prevalent way to do it back then is to put this part in a fixed range at the beginning of the address space, and then put the ram afterward. That's the way it was designed on most home micro computers.
IBM and Microsoft (per Bill Gate's own admission) collaborated in the designing of the PC architecture. Surprisingly, they did NOT follow the prevalent way. They opted to sereve the address space 00000-9FFFF for RAM and A0000-FFFFF for the rest. (That's where the 640k come from: it's the first address with a hex "letter" instead of "number" because that the arbitrary point they choose for the RAM/ROM split).
Had they chosen to go for the most prevalent way, problems would never had arisen, the upper simply being pushed as newer CPUs with wider buses became more widespread.
But, IBM though of the PC as a glorified terminal with which to talk to their big irons. They didn't see much interest in providing much RAM. The important part was their minicomputers and mainframe, and those DID have more provision built-in. ...except it wasn't. If they were paying a little bit more attention to what was happening around them, they might have thought a little bit better and thought of a design which doesn't put a restriction on memory.
Microsoft on their side, came from a background of 8-bit home micro computers, in which 64k was huge.
As Billy said, 640k could seem to them as being more than anything ever needed. They could write software running inside 64k. The PC could even ship with incredible amount of RAM like 128k. Why would anyone need addresse of more than 640kb.
Also the first PC were equiped with amounts of RAM varying between 16k and 256k - so it was not "640k of RAM, then BIOS" but more like "a few kb of RAM, a huge unused gap in the address space, then BIOS" - given the huge gap, the address split might have looked reasonable...
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Some of the richest uranium deposits known are in northern Canada, in locations so remote they'd have to fly the yellowcake (uranium oxide in the form of U3O8) out in cargo planes. Today the spot price (25th July 2013) for yellowcake is $40 per lb. which makes it uneconomic to work that ore body given the logistics costs involved. If the price of yellowcake tripled then maybe it would start to be worthwhile opening up those orebodies. That tripling of the raw material price would only increase the price of nuclear-generated electricity by about 1.5 cents per kWh though because the fuel is still ridiculously cheap and a minor part of the total cost of nuclear electricity.
Long time back before WWII, nobody was really interested in uranium, it had little or no industrial uses. After WWII everybody started looking for it but it was thought at that time it was rare hence the early interest in thorium, breeder reactors etc. It turned out that it was actually quite a common substance with lots of easy-to-mine ore bodies in places all over the world. We're still working on the easiest to extract sources of uranium because they're cheap. As they run out we'll dig up more expensive ores, lesser grades requiring more digging and processing and the price will rise.
The wonderful thing is that uranium is so compact a source of energy that we don't need to dig up a lot of ore to keep the lights on, not compared to coal or oil or gas. The US' entire electricity demand could be met by a couple of million tonnes of uranium ore each year, without reprocessing spent fuel -- if that was done (at a price) a few hundred thousand tonnes of ore would suffice. In comparison it would take about 4 billion tonnes of coal each year to do the same job.
The bottom line price for uranium is extraction from seawater -- Japanese experiments suggest that would cost about $300 per kilo of uranium metal although nobody's bothered to build a pilot extraction plant because, guess what, uranium is so cheap right now it's not financially viable to even try. There's enough extractable uranium dissolved in the world's oceans to power the world for millenia if we had to.