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Comment Re:Connecting things to the internet. (Score 1) 125

The successful solution implemented by several cities has been to have real live people in a central traffic command centre monitor and adjust lights. It still requires the sensors and lights to be networked, it just doesn't use software to automatically adjust them (at least not during peak times).

Why are people still talking about stupid things? Because people who think you should give them money for their "ideas" have to come up with those ideas somewhere. It's different this time. Really.

Comment Re:Connecting things to the internet. (Score 1) 125

That's a start, but there is also value in having this traffic light know that up the street there's a backup so it might as well let the cross traffic go despite what the sensor is telling it. Or conversely, that light up the street might want to turn green for the group of cars that just went though this one.

Internet connected appliances are dumb. That was tried during the last bubble.

Comment Re:This pretty much sums up IoT ... (Score 1) 125

It depends on what it is. Cab companies are finding out that having your cabs (or their drivers) connected to the Internet is very important. We already discovered that hooking refrigerators up to the Internet was kind of stupid.

In terms of "smart" cities, traffic sensors at important intersections and central control can really improve traffic flow. Parking meters you can pay by app are very convenient (provided the fee is reasonable). Busses with GPS on board and an app to show when they're coming seems like it should be a no brainer. But a lot of the other stuff companies are trying to push is just stupid.

Comment Re:Not really. (Score 1) 380

Actually, yes, it does. There's also a web page written by a fusion researcher featuring that graph and it gives a good, accessible rundown on the progress that's been made to date and a good projection of what still needs to be done.

Keep in mind, IIRC, those projections were made in 1976. It wasn't "we need more money" it was a set of recommendations for the US to decide how aggressively to pursue fusion research, from Manhattan project level to "you might as well not even bother."

Comment Re:A step forward, but... (Score 1) 380

Suppose we're using a two stage reaction:

D + D -> 3He + n + 3.27 MeV
D + 3He -> 4He + H + 18.3 MeV

That gives us 21.57 MeV = 3.5e-12 J per 3He atom. World energy usage is 6.0e20 J.

To supply that, assuming we have a 100% efficient reaction, we'd need to produce 1.6e32 4He atoms, which is 2.7e8 mole, or 1.0e6 kg

A standard 11" balloon apparently requires .015 m^3 of helium, which is about 2.7 g. So we could inflate about 400 million balloons. Incidentally, they could lift about 4000 tonnes.

Unless I made a mistake.

Comment Re:Mission accomplished (Score 2) 380

It's good to have options. As you say, wind and solar are doing just fine. They're today's technologies. Fusion is looking promising. It's the technology of tomorrow. The power density, self containment and controllability of a practical fusion reactor lets you do things that wind and solar can't.

"We learn from history that we learn nothing from history." -- George Bernard Shaw

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