 So guys, we are here on location at General Fusion, where they are attempting to build the world's first commercially viable nuclear fusion power plant, and uh... It might not look like much, but the only way that the technology inside could be any more space age would be if I was actually shooting on the moon today, so why don't we go take a look? Oh! After I tell you about TunnelBear! TunnelBear makes really simple, easy to use VPN applications so you can enjoy a more open internet. Check them out at tunnelbear.com slash LTT. So, what exactly is nuclear fusion? Well, on an atomic level, basically you take a couple of hydrogen atoms, get them up to a really high temperature, and then you like, smash them together. Once they're fused, you'll be left with a helium atom. Oh, I'm Steven today. So, because one proton plus one proton equals two protons, and you'll get some energy. Or rather, you'll get a lot of energy, like, like ten times what you'd get from a nuclear fission reaction, like the ones that power traditional nuclear plants. So, that all sounds super cool already, and we haven't even gotten to the best part yet. Nuclear fusion works around the clock, unlike solar or wind, and it's 100% clean and safe. The reaction is actually incapable of causing a meltdown or other radioactive incident. And as much as this might look like some kind of a, you know, death ray, the only direct byproducts are helium, like for party balloons, and energy. So, no depleted uranium seeping into the environment for thousands of years, no greenhouse gas emissions, and get this, the fuel for it is practically free. You input deuterium, a hydrogen isotope that you can extract from ordinary seawater with a centrifuge. Oh, that's awful. And lithium. And some critics might point out that these materials, particularly lithium, are not technically renewable, but at least for heavy water, the reaction uses so little of it, and there's enough sitting around that by the time we run out, the sun will have enveloped the earth anyway. So, yeah, I think we are probably good there. Well, okay then Linus. If it's so great, why is fusion power taking so long? Ah, I'm glad you asked. While the fundamental principles have been reasonably well understood for decades, the engineering and science required to build something practical in the real world are, well, in scientific terms, a total b**** to get right. In order for nuclear fusion to occur between two hydrogen atoms, they need to be heated up to 150 million degrees Celsius. That's about 10 times hotter than the center of the sun, and you've got to do that efficiently. No one's gonna buy a fusion power plant that consumes more power than it outputs. Duh. So then how would you get something that hot? Ah, well, you could use a device called a tokamak to make a plasma donut and then manipulate it with liquid helium cooled magnets. Sounds promising. You could take a, let's see here, peppercorn sized piece of frozen deuterium and then bombard it from all sides at exactly the same time with what is quite literally the world's most powerful laser effectively blowing up the outside, compressing the inside enough to start the reaction, and both of those methods have actually succeeded at using nuclear fusion to get close to producing more power than they consumed. But the problem is that via both of those methods, it is extremely difficult to actually harness the power to generate electricity. Ah, not gonna do that again. General fusion's approach is kind of like a hybrid of the other two, and it operates kind of like a super high-tech diesel engine. So first they use one of these guys to create a 5 million degree ball of plasma, then they rapidly compress it with steam powered pistons, the pressure from which heats it to 150 million degrees. At that point, the deuterium kind of ignites releasing energy. And if all this sounds difficult, don't worry, in real life, it is way harder. This is general fusion's last generation large scale plasma injector, where they prototype their process of creating a plasma of sufficient quality that it can survive for long enough for the pistons in the compression chamber to fully compress it. So during a cycle, these valves right up here will inject just two milligrams of deuterium evenly into the chamber, which goes all the way around in a ring. Then one million amps at 15,000 volts, so this is about the same as your average lightning bolt, goes across the electrical feed right here and strips the electrons off the deuterium, creating a ball of plasma. These particles then spin around the ball of plasma, wrapping it in its own magnetic field, creating an insulating layer around the plasma to give it a longer lifespan. From there, these big electromagnets here will push the ball of plasma out the front of the injector into the compression chamber, which would be under this part right over here. Now, the rest of this guy, which is actually about the front two thirds, is just for data collection. Every test that they run generates about a gigabyte of data, and even after 150,000 experiments, there is still work to do. I guess that's why General Fusion is so open about showing off their work, because even if you stole all the drawings and built yourself one of these machines, there are literally hundreds of thousands of variables to tune for plasma quality. So you basically have built yourself a multi-million dollar paperweight. On the subject of millions of dollars, much of the research is actually done on smaller, less expensive, little injector prototypes like Spector here. These guys only take a couple of months to create instead of years, and they give the team valuable insight in between larger projects. Mind you, even this kind of thing does not come easy. Every aspect of this research is complex and expensive, like, okay, here. How do you know if your plasma is at 5 million degrees? You can't just stick a K-probe in it. Ah, so it turns out you have to shine a super strong laser through the plasma and then measure the small bit of light that is deflected by the plasma. And this is only about one in every quadrillion photons that you pump in that get turned into some kind of useful signal. So interpreting that data is quite literally the full-time job of Bill here, who has a PhD from the University of Maryland. And that is just one example. But they are making progress. Inside this cage is the largest and most powerful plasma injector in the world. It's the latest generation of the one that we looked at earlier, and they're running tests on it every day in hopes of using a similar model to create a fusion demonstration plant in as little as four to five years. So unlike the other one, this guy is actually hooked up. Do you see all these containers around me? These are capacitor banks. So when all of them are operating, they'll be capable of 20 gigawatts of power. That's enough to send 16.5 DeLoreans back in time simultaneously. The problem, though, is that when you're unleashing a lightning bolt worth of power, you throw out a ton of electronic interference. It's such a big problem that all of the sensor data has to be transmitted through fiber optic cables to a nearby Faraday cage full of General Fusion's own custom-made digitizer boards. They ended up designing their own because creating an electronics engineering department was cheaper than buying gear like this off the shelf. Now, General Fusion weren't the first ones to come up with the idea of smushing plasma, but the U.S. Naval Research Labs' incredibly named Project Linus ended up getting abandoned back in the 1970s because there were a couple of problems they just couldn't overcome. Behind me is a couple of solutions. This is General Fusion's piston-driven compression chamber proof of concept. Now, the real one would have many more pistons, but the operating principle would be similar. Every piston would push down simultaneously with a tolerance of about 10 microseconds injecting liquid metal stored in the pistons and in the 1000 RPM spinning grid on the inside, and that metal would squeeze the plasma bubble that would be injected from the top. Now, the timing for all of this has to be so precise because much like squeezing a water balloon in your hands, if you don't compress it evenly, then it'll kind of splurt out or break apart, and that would cause a misfire. Assuming everything goes right though, and the simulations say it should, the fuel ignites, fusion occurs, and that liquid metal gets heated to about 600 degrees Celsius, after which it gets circulated through insulated pipes by a magnetohydrodynamic pump to a traditional steam turbine power generator, just like what you would find at a coal or a natural gas power plant today, which should make General Fusion's solution sort of a drop-in upgrade for an existing facility. Now, fun fact, it is not a perpetual motion machine because it does require a constant supply of fuel, but some of the steam that gets generated is actually going to be used to actuate the pistons, keeping the cycle going. General Fusion hopes that once they reach production, they'll be able to run one of these reactions every second, generating about 100 to 200 megawatts of power, about the sweet spot for replacing existing coal power plants in developed countries, and not so much that it would blow up the power distribution systems in developing countries, a market where the most new power generation will have to happen in the coming years. Now, none of this is a sure thing, I mean, nothing in life is, but if General Fusion and its investors, which includes Jeff Bezos, apparently, by the way, can stay on course, then the future looks really bright, not just for their company, but also for the world. Speaking of companies with bright futures, are you finding as a freelancer or small business owner that the thing holding you back is spending your time on complicated accounting software instead of just doing your work? Well, FreshBooks is the solution you're looking for. 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