A nuclear power plant is large and complex, and one of the biggest reasons is safety. Splitting radioactive atoms is inherently dangerous, but the energy unleashed by the chain reaction that ensues is the entire point. It’s a delicate balance to stay in the sweet spot, and it requires constant attention to the core temperature, or else the reactor could go into meltdown.
Today, nuclear fission is largely produced with fuel rods, which are skinny zirconium tubes packed with uranium pellets. The fission rate is kept in check with control rods, which are made of various elements like boron and cadmium that can absorb a lot of excess neutrons. Control rods calm the furious fission boil down to a sensible simmer, and can be recycled until they either wear out mechanically or become saturated with neutrons.
Nuclear power plants tend to have large footprints because of all the safety measures that are designed to prevent meltdowns. If there was a fuel that could withstand enough heat to make meltdowns physically impossible, then there would be no need for reactors to be buffered by millions of dollars in containment equipment. Stripped of these redundant, space-hogging safety measures, the nuclear process could be shrunk down quite a bit. Continue reading “No-Melt Nuclear ‘Power Balls’ Might Win A Few Hearts And Minds”→
When was the first nuclear reactor created? You probably think it was Enrico Fermi’s CP-1 pile built under the bleachers at the University of Chicago in 1942. However, you’d be off by — oh — about 2 billion years.
The first reactors formed naturally about 2 billion years ago in what is now Gabon in West Africa. This required several things coming together: natural uranium deposits, just the right geology in the area, and a certain time in the life of the uranium. This happened 17 different times, and the average output of these natural reactors is estimated at about 100 kilowatts — a far cry from a modern human-created reactor that can reach hundreds or thousands of megawatts.
The reactors operated for about a million years before they spent their fuel. Nuclear waste? Yep, but it is safely contained underground and has been for 2 billion years.
Here on Earth, the ability to generate electricity is something we take for granted. We can count on the sun to illuminate solar panels, and the movement of air and water to spin turbines. Fossil fuels, for all their downsides, have provided cheap and reliable power for centuries. No matter where you may find yourself on this planet, there’s a way to convert its many natural resources into electrical power.
But what happens when humans first land on Mars, a world that doesn’t offer these incredible gifts? Solar panels will work for a time, but the sunlight that reaches the surface is only a fraction of what the Earth receives, and the constant accumulation of dust makes them a liability. In the wispy atmosphere, the only time the wind could potentially be harnessed would be during one of the planet’s intense storms. Put simply, Mars can’t provide the energy required for a human settlement of any appreciable size.
The situation on the Moon isn’t much better. Sunlight during the lunar day is just as plentiful as it is on Earth, but night on the Moon stretches for two dark and cold weeks. An outpost at the Moon’s South Pole would receive more light than if it were built in the equatorial areas explored during the Apollo missions, but some periods of darkness are unavoidable. With the lunar surface temperature plummeting to -173 °C (-280 °F) when the Sun goes down, a constant supply of energy is an absolute necessity for long-duration human missions to the Moon.
Since 2015, NASA and the United States Department of Energy have been working on the Kilopower project, which aims to develop a small, lightweight, and extremely reliable nuclear reactor that they believe will fulfill this critical role in future off-world exploration. Following a series of highly successful test runs on the prototype hardware in 2017 and 2018, the team believes the miniaturized power plant could be ready for a test flight as early as 2022. Once fully operational, this nearly complete re-imagining of the classic thermal reactor could usher in a whole new era of space exploration.
On August 8th, an experimental nuclear device exploded at a military test facility in Nyonoksa, Russia. Thirty kilometers away, radiation levels in the city of Severodvinsk reportedly peaked at twenty times normal levels for the span of a few hours. Rumors began circulating about the severity of the event, and conflicting reports regarding forced evacuations of residents from nearby villages had some media outlets drawing comparisons with the Soviet Union’s handling of the Chernobyl disaster.
Today, there remain more questions than answers surrounding what happened at the Nyonoksa facility. It’s still unclear how many people were killed or injured in the explosion, or what the next steps are for the Russian government in terms of environmental cleanup at the coastal site. The exceptionally vague explanation given by state nuclear agency Rosatom saying that the explosion “occurred during the period of work related to the engineering and technical support of isotopic power sources in a liquid propulsion system”, has done little to assuage concerns.
The consensus of global intelligence agencies is that the test was likely part of Russia’s program to develop the 9M730 Burevestnik nuclear-powered cruise missile. Better known by its NATO designation SSC-X-9 Skyfall, the missile is said to offer virtually unlimited flight range and endurance. In theory the missile could remain airborne indefinitely, ready to divert to its intended target at a moment’s notice. An effectively unlimited range also means it could take whatever unpredictable or circuitous route necessary to best avoid the air defenses of the target nation. All while traveling at near-hypersonic speeds that make interception exceptionally difficult.
Such incredible claims might sound like saber rattling, or perhaps even something out of science fiction. But in reality, the basic technology for a nuclear-powered missile was developed and successfully tested nearly sixty years ago. Let’s take a look at this relic of the Cold War, and find out how Russia may be working to resolve some of the issues that lead to it being abandoned. Continue reading “Echos Of The Cold War: Nuclear-Powered Missiles Have Been Tried Before”→
Have you been watching Chernobyl? Well, so has everyone else. Right now it seems the whole Internet is comprised of armchair dosimetrists counting roentgens in their sleep, but [Mark Wright] doesn’t need a high-budget TV show to tell him about the challenges of wrangling the atom with 1980s technology. He’s done it for real. His memories of working at a Westinghouse Pressurized Water Reactor over 30 years ago are so sharp that he’s been building a nuclear reactor “simulator” running on the Raspberry Pi that looks nearly as stressful as sitting in control room of the real thing.
The simulator software is written in Python, and is responsible for displaying a simplified overview of the reactor and ancillary systems on the screen. Here all the information required to operate the “nuclear plant” can be seen at a glance, from the utilization of individual pumps to the position of the control rods.
By pretty much any metric you care to use, the last couple of decades has been very good for the open source movement. There was plenty of pushback in the early days, back when the only people passionate about the idea were the Graybeards in the IT department. But as time went on, more and more developers and eventually companies saw the benefit of sharing what they were working on. Today, open source is effectively the law of the land in many fields, and you don’t have to look far to find the community openly denouncing groups who are keeping their source under lock and key.
In the last few years, we’ve even seen the idea gain traction in the hardware field. While it’s not nearly as prevalent as opening up the software side of things, today it’s not uncommon to see hardware schematics and PCB design files included in project documentation. So not only can you download an open source operating system, web browser, and office suite, but you can also pull down all the information you need to build everything from a handheld game system to an autonomous submarine.
With so many projects pulling back the curtain, it’s not unreasonable to wonder where the limits are. There’s understandably some concerns about the emerging field of biohacking, and anyone with a decent 3D printer can download the files necessary to produce a rudimentary firearm. Now that the open source genie is out of the bottle, it seems there’s precious little that you can’t download from your favorite repository.
Scratching an exceptionally surprising entry off that list is Transatomic, who late last year uploaded the design for their TAP-520 nuclear reactor to GitHub. That’s right, now anyone with git, some uranium, and a few billion dollars of seed money can have their very own Molten Salt Reactor (MSR). Well, that was the idea at least.
So six months after Transatomic dumped a little under 100 MB worth of reactor documentation on GitHub, is the world any closer to forkable nuclear power? Let’s find out.
The Chicago Pile led to the Manhattan Project, which led to the atomic bomb. In Germany, there were similar efforts with less success, and now we have physical evidence from the first attempted nuclear reactor in Germany. In Physics Today, there’s a lovely historical retrospective of one of the ‘fuel cubes’ that went into one of Germany’s unsuccessful reactor experiments. This is a five-centimeter cube that recently showed up in the hands of a uranium collector. In the test reactor, six hundred of these cubes were strung along strings and suspended like a chandelier. This chandelier was then set inside a tub surrounded by graphite. This reactor never reached criticality — spectroscopy tells us the cube does not contain fission products — but it was the best attempt Germany made at a self-sustaining nuclear reaction.
The biggest failing of the Arduino is the pinout. Those header pins aren’t all on 0.1″ centers, and the board itself is too wide to fit on a single solderless breadboard. Here’s the solution to that problem. It’s the BreadShield, an Arduino Uno-to-Breadboard adapter. Plug an Uno on one end, and you get all the pins on the other.
There’s a new listing on AirBnB. this time from NASA. They’re planning on opening the space station up to tourism, starting at $35,000 USD per night. That’s a cool quarter mil per week, launch not included. The plan appears to allow other commercial companies (SpaceX and whoever buys a Boeing Starliner) to accept space tourists, the $35k/night is just for the stop at the ISS. Costs for launch and landing are expected to be somewhere between $20 and $60 Million per flight. Other space tourists have paid as much: [Dennis Tito], the first ‘fee-paying’ space tourist, paid $20M for a trip to the ISS in 2001. [Mark Shuttleworth] also paid $20M a year later. Earlier space ‘tourists’ paid a similar amount; Japanese journalist [Toyohiro Akiyama] flew to Mir at a cost of between $12M and $37M. Yes, the space station is now an AirBnB, but it’s going to cost twenty million dollars for the ride up there.