The Long History Of Fast Reactors And The Promise Of A Closed Fuel Cycle

The discovery of nuclear fission in the 1930s brought with it first the threat of nuclear annihilation by nuclear weapons in the 1940s, followed by the promise of clean, plentiful power in the 1950s courtesy of nuclear power plants. These would replace other types of thermal plants with one that would produce no exhaust gases, no fly ash and require only occasional refueling using uranium and other fissile fuels that can be found practically everywhere.

The equipment with which nuclear fission was experimentally proven in 1938.

As nuclear reactors popped up ever faster during the 1950s and 1960s, the worry about running out of uranium fuel became ever more present, which led to increased R&D in so-called fast reactors, which in the fast-breeder reactor (FBR) configuration can use uranium fuel significantly more efficiently by using fast neutrons to change (‘breed’) 238U into 239Pu, which can then be mixed with uranium fuel to create (MOX) fuel for slow-neutron reactors, allowing not 1% but up to 60% of the energy in uranium to be used in a once-through cycle.

The boom in uranium supplies discovered during the 1970s mostly put a stop to these R&D efforts, with some nations like France still going through its Rapsodie, Phénix and SuperPhénix designs until recently finally canceling the Generation IV ASTRID demonstrator design after years of trying to get the project off the ground.

This is not the end of fast reactors, however. In this article we’ll look at how these marvels of engineering work and the various fast reactor types in use and under development by nations like Russia, China and India.

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Resurrecting A Recalcitrant SE/30

The Macintosh SE/30 is well regarded as the choice pick of the compact Mac line. Packing a powerful 68030 processor and with the capability to use up to 128 MB of RAM, it brought serious grunt to bear in a tight form factor. With these machines now over 30 years old, they’re often quite worse for wear. [This Does Not Compute] had his work cut out for him getting this particular example up and running. (Video embedded below.)

With the computer displaying the famous SimasiMac screen on startup, it was sadly non-functional when switched on. [This Does Not Compute] went through all the usual attempts to fix this – washing the board, recapping, checking potentially broken traces – all to no avail. After much consternation, the fix was not so hard – a fresh set of RAM helped cure what ailed the Mac.

With the Mac now showing some signs of life, there was more to do. The floppy drive refused to boot, ejecting disks and failing to read anything. A head cleaning proved helpful, but not enough. It was only when the head motor’s worm gear was relubricated, enabling it to seek properly, that the drive was successfully able to boot. The hard drive proved resistant of any attempts to get it to work, so was replaced with a SCSI2SD instead.

With the suite of repairs completed, the SE/30 was once again up and running. With a little elbow grease, the case and keyboard turned up a treat, too. [This Does Not Compute] now has one of the all-time classic Macs in excellent condition.

We’ve seen some great restorations over the past – this Commodore 64 full of dirt was a particularly compelling story. Video after the break.

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Hacking The IKEA TRÅDFRI LED Power Supply

Just because something is being actively documented and tampered with by enthusiastic hackers doesn’t mean the information is handily centralized. There can be a lot of value in gathering disparate resources in one place, and that’s exactly what [Trammell Hudson] has done with his resource page for hacking the IKEA TRÅDFRI LED power supply with wireless interface. Schematic teardown, custom firmware images, it’s all there in one convenient spot.

Back in 2017, the IKEA TRÅDFRI hacking scene was centered around the LED light bulbs but as the group of products expanded, the rest of the offerings have also gotten some attention.

Why bother tampering with these units? One reason is to add features, but another is to make them communicate over your own MQTT network. And MQTT is the reason you are only a Raspberry Pi and a trip to IKEA away from the beginnings of a smart home that is under no one’s control or influence but your own.