Slashdot is powered by your submissions, so send in your scoop


Forgot your password?

Comment Re:No it isn't (Score 3, Insightful) 215

> The problem is inefficiency. Power drops with the square of distance.


That's how radio works.

Actually the resonant schemes DON'T use radio, they use inductance; which is just magnetic fields; and they work at much lower frequencies.

By contrast, radio is a particular mixture of magnetic and electric fields that propagate to infinity, and you tend to lose them. That was the genius of Marconi, to get the mix right.

But magnetic fields on their own don't propagate, that's partly why magnets don't go flat. The energy hangs around the transmitter and can be absorbed by a suitable receiver.

Comment Re:As it was before (Score 1) 215

Except that now the device can have chips in to measure the amount of power being supplied, and if somebody hasn't paid, can cut it off.

And actually the original problem about how you can be billed was solved by television broadcasters; mostly it relied on people being honest, and occasionally driving around with a truck with equipment to sniff out people that were stealing.

Comment Re:Efficiency should kill it (Score 1) 284

There's lots of electricity in things that aren't in your house, in street lights, shops, factories etc. etc.

The total energy per capita for example is over 5kW in the UK for example (10kW in America), check out the final column in this table:

Things like mobile phones are completely irrelevant really, and laptops are pretty much irrelevant.

I saw a number which was ~2kW by an academic for the UK, that IRC would have been electricity only (presumably he took total electricity supply and divided by population).

Comment Re:Efficiency should kill it (Score 2) 284

These devices use very little power.

A typical person in the Western world uses, on average, 2+ kW. That's not 2kWh per day, that's 2+ kWh EACH AND EVERY HOUR.

These devices that are proposed to be charged wirelessly are usually just a few watts, about 1/1000 of what the person is using; so even if the power efficiency halved for those particular devices, it would make essentially sod-all difference.

The other thing is that in many cases if it's easier to recharge, then you don't need such a big battery; batteries are incredibly expensive compared to wall supplied power.

Comment Re:Working as intended (Score 1) 333

You have a very rosy view. And that's not what happened in this case; for example. There are a large number of admins that will quite happily remove primary sources, even though the actual policy is much more nuanced, and ALLOWS adding material from twitter and blogs to be used in cases like this; a clear public statement by an author that something or other wasn't his inspiration, while it cannot be taken as proof of that, could easily have been mentioned in the article.


blah says this,[ref1] somebody else said something else,[ref2] but the author disagreed and said something else.[ref3]

Protip: sanctions like you describe are usually more to do with other users/admins ganging up on someone, not so much not what they do right or wrong.

Comment Re:Working as intended (Score 1) 333

It really doesn't really work like that, although it might seem like that if you're a novice.

The admins have a rough set of rules they actually use, that are somewhat disconnected from the real rules; admins rarely read the rules.

The way it works is that each admin basically makes a decision what the rules 'really' mean, and any given admin will hardly ever override what another admin decides (they call this 'wheel warring').

The admins, by and large, have a pretty hazy understanding of the rules; usually it seems like they've just read the title of the rule, and imagined what it said, and they are in deep contempt of anyone that really does understand the rules (they call that 'wikilawyering' and it's an insult.) If you quote the rules to them, you will get absolutely nowhere. The admins will very often apply rules in a way that the rules themselves explicitly say is not what they mean.

Slashdot Top Deals

You can tune a piano, but you can't tuna fish. You can tune a filesystem, but you can't tuna fish. -- from the tunefs(8) man page