字幕表 動画を再生する 英語字幕をプリント Nuclear power is like the unloved child of sustainable energy. It’s got so much potential, but it only gets noticed when it does something wrong. If only people could just see how cool it is. Ahoy-hoy fallout boys and girls, Julian here for DNews and today we’re going to talk about nuclear power. Now I know this is an element that splits the internet and leads to an explosive chain reaction (see what I did there?) but we are going to gingerly handle this sensitive material like the science-loving adults that we are. The most popular green energies people like to discuss are solar and wind power, and I agree, the idea of harnessing the phenomenal cosmic power of the sun and...snazzy earthy blowingness of wind is pretty cool. But we’re going to have to upscale our production in a big way if we are going to meet demands. Last year in the US, wind provided 4.13% of our power, and solar? A microscopic .23%. So we’d need almost 25 times as much of each just to meet demands, not to mention we’d have to overproduce and store energy for when it’s dark and not windy. And we’ll have to build the storage facilities. Meanwhile nuclear provides 19% of our energy in this country, but we’re using an idea we haven’t updated since the 50’s; the Light Water Reactor. Light Water Reactors split uranium 235 to heat water. In the US this water is kept at extremely high pressures to keep it in liquid form. This super-heated super-pressurized water then heats a second loop of water, turning it to steam and driving a turbine. Reactors like this became widespread because of their simplicity, but they only use about 5% of their fuel and the waste is radioactive for 10,000 years. The fuel can be recycled though. France has been relying on nuclear power since the 70s and by recycling, the total amount of high-level waste that could give a family of 4 power from when the kids are born until they’re in college is about the volume of a cigarette lighter. You still have to put that somewhere, and waste storage is one of the major dividing issues. Don’t kid yourself though, in California alone the production of solar panels makes over 13 million tons of toxic waste annually, and that’s just stored somewhere too. There’s no such thing as a free lunch. Molten Salt Reactors were a competing idea that were shelved in the 60’s, despite the fact that engineers built reactors that proved they could work. Lately interest in them is growing because of their potential benefits. The concept is liquid salt is the reactor’s coolant, meaning it doesn’t need to be pressurized like it’s light water counterparts. This means there’s no complications from loss of pressure like the rapid expansion of radioactive gas or loss of coolant to the reactor. In fact it’s possible to design molten salt reactors in such a way that they are self-regulating and melt-down proof. Pretty neat, huh? And it gets better, Molten Salt Reactors that would use Thorium as their fuel source would use almost 100% of their fuel. And they would breed more of their own. When thorium 232 is hit with a neutron, it absorbs it and eventually decays into uranium 233. U-233 is fissile, and shoots out 2 or 3 more neutrons. These can keep the chain reaction going and also bombard more thorium to generate more uranium. Thorium has the benefit of being 3 to 4 times more abundant than uranium, and right now is just a hazardous waste byproduct of rare-earth mining. So we’re already digging the stuff up, and have nothing to use it for. Thorium 232 has a half-life of over 14 billion years, but once it’s been used in a Liquid Fluoride Thorium Reactor, 80% of the waste decays to safe levels in 10 years. A small amount would need up to 300 years before it was safe, but that beats 10,000 years by a long shot. And the products of a LFTR reactor are harder to use for nuclear weapons, so there’s less of a worry about nuclear proliferation. Not that we don’t have enough weapons to murderize everyone already. MSRs still have issues of their own to work out, like keeping the liquid fluorides from corroding the metal they’re stored in. China thinks they can solve these problems and make safer, more sustainable, and less polluting nuclear power. They’ve planned to have a functioning thorium reactor within the next decade. If you’re worried about the storage of nuclear waste, Anthony has some pretty cool info for you here about how it’s compacted and stored. What are your thoughts on the future of energy? Do you have a personal favorite solution? Let us know in the comments. I’ll see you next time on DNews.
B1 中級 米 クリーンな原子力の未来がやってくる (The Future Of Clean Nuclear Energy Is Coming) 329 22 Jack に公開 2021 年 01 月 14 日 シェア シェア 保存 報告 動画の中の単語