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New Wave of Fusion and Robot Innovation at MIT
An anonymous reader writes "Popular Mechanics has been getting some great access inside the labs at MIT all week, and they've gotten some interesting looks at developing technologies. Robot-assisted rehab with gaming-style controllers comes out of the biomechanics lab, blind and crash-proof UAV testing with F/X cameras is being done at the aerospace controls lab, and work on electric scooters with super-cheap assembly is proceeding at the Media Lab. Perhaps most exciting is a fight for funding while the holy grail of clean fusion power in reach at the plasma center. The article on fusion predicts, "We'd see economically feasible fusion power by 2035, at the earliest, and increasingly efficient commercial reactors somewhere in the middle of the century."
The truth is, we still don't fully understand how plasmas act in the real world. The article alludes to this, by mentioning turbulence and instability. Fluid models and magnetohydrodynamics just aren't detailed enough, and full-blown simulations are far too complex to be of much use on a fusion-reactor scale.
A key concept is "transport". What a fusion reactor requires is to keep heat bottled up. The ions in particular need to be kept hot so that they can fuse. What happens, though, is that heat gets dumped from the ions into the electrons (which are useless for fusion) at a rate which exceeds theoretical predictions -- one of many "anomalous transport" phenomena. (Great phrase, which you may recognize from HL.)
Bottom line: we need to do more research on fundamental plasma physics for fusion. Yet for whatever reason, fusion funding has been dropping for decades.
Once we discover a large reservoir of concentrated easy to mine hydrogen it will make sense to have a hydrogen energy economy. Currently, I can't think of many things more idiotic than burning carbon fuels to make energy at low efficiency, which is transmitted at low efficiency to a plant, which is harnessed at low efficiency to make hydrogen, which is transported by a familiar large infrastructure of energy using vehicles, to a station where you can fill up your hydrogen car that can burn the hydrogen at low efficiency. I wouldn't be surprised if the amount of energy being consumed (at the plant) compared to the amount actually usable by the hydrogen car is near 1%. What a fucking waste.
Or we could just cut all that shit and have cars that run at 20-40% efficiency burning carbon fuels.
You should look China when you are talking about Scooter.
They have a wide selections in Carrefour, or whatever Supermarket.
Price tag: ~1200RMB (150USD). Probably can goes up to 30MPH.
May be not as stylish as the MIT one, but definitely cheap, usable and actually are all over the streets. And there are more scooter than bicycle on the street.
Some models looks just like more than a hack of Bicycle + Motor + Battery pack, but works! Most design with battery pack can be swap out, and can be plugged to the main directly for charging. I have seen the janitor in Office bringing her pack upstair for charging.
It's just cheap!
It's not just him ya know. Pretty-much every fusion researcher on the planet who isn't working on a Tokamak has had their funding dry up. This isn't because Tokamaks are so close to being ready, quite the opposite.
How we know is more important than what we know.
Most of the energy from DT fusion comes out in the form of fast neutrons. What's envisioned (emphasis on envisioned) is to have a lithium "blanket" surrounding the first reactor wall that will 1) be heated by neutrons 2) breed tritium for the fuel cycle. For bonus points make this a molten lithium system and run it through a heat exchanger. The rest is just a standard balance of plant: steam generator and turbine. Nothing exotic.
The main problem is dealing with all these pesky neutrons. Aneutronic fusion avoids them, but is far more difficult than DT fusion.
Of course the first generation of clean energy infrastructure will have to be built using dirty energy. But then you use the energy from those sources to build the next generation. Like bootstrapping a compiler on a new system. You have to compile it with the old compiler before you can compile it with itself.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton