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Comment Re:Solar cars aren't viable, but that isn't the po (Score 1) 58

Hey, I'm a member of the solar car team from University of Toronto, we're also racing this year. Were you around for the 2007 WSC?

Unfortunately, I can't go to the race personally. You're lucky that you get to go as an alumni. Good luck to you guys! Say hi to the UofT team if you see them, they're a friendly bunch. :) (maybe a little disgruntled from the work and lack of sleep)

Comment Re:Definitely interesting, but I am asking myself. (Score 4, Informative) 57

1) Current manufacturing process are struggling to get transistors any smaller than millions of molecules each, and Benzine, the molecule specifically used here, is not very big.

The current state of the art manufacturing process is at 32nm, which is much less than millions of molecules each. 32nm is 320 angstrom, so we're at roughly 300 molecules size.

Comment Re:So it's $70 a year.... (Score 1) 697

I'm pretty sick and tired of people not reading articles properly. This is not directly totally at you, you just happen to be the last person among others. It's just depressing, and makes me wonder why I even provide links to back up my claims.

Anyway, from the article I linked to earlier, here are some important quotes:

"If you want to promote energy efficiency you don't subsidize the price of electricity, you've got to raise it," said Jack Gibbons, lead author of the study

Ontario Power Generation also gets a below-market return on its generating assets that amounts to $850 million annually.

"In essence, a full-cost pricing strategy represents a tax shift from subsidizing wasteful consumption to rewarding efficiency, which in turn is a much more economically efficient and beneficial use of government revenues," according to the study.

The rebate that's mentioned in the article is the new rebate scheme they want the subsidy to be replaced with, not the current subsidy. And you didn't answer my question, why would the rate be so much cheaper in Ontario versus other regions if there's no subsidy?

Comment Re:So it's $70 a year.... (Score 1) 697

Just from first few results from google. Cost overruns from large power projects is of the reason why electricity rates is higher, but consumers don't see the effect of those cost overruns due to the subsidies.

Why do you think the rates are so much higher for regions? It's definitely not because we're that much more efficient.

Comment Re:blackouts (Score 1) 332

What happens next in a fully interconnected North American grid is that quarter of a billion people lose power.

No, that's not true. Read all of my posts and not just focus on one small part of it. The August 2003 blackout could have been prevented through 2 ways. First way is following the NERC reliability policies, which FirstEnergy did not do. The second way is implementing situational awareness on the grid that would have prevented the blackout. This is currently being worked on after the recommendation from the joint task force report. The worst case that would have happened would be the area controlled by FirstEnergy goes without power, but it won't drag down the rest of the grid.

The risk management answer is: from any given local grid, don't routinely import or export more electricity than your local grid is capable of surviving should that import or export suddenly cease.

They already do that. That's the N-1 criterion I mentioned earlier.

Comment Re:Why 22 sq miles? (Score 1) 332

One thing I can think of is that the AC transmission lines for the 3 different interconnect aren't all at the same location. There probably isn't a location where all 3 systems meet, and you need to have access to HVAC lines in order to transfer power to and from each system. So logical location would be somewhere that is closest to all 3 systems.

While you're correct that it's cheaper to have shorter superconducting DC lines, they don't seem to be that expensive. Their website indicates it's on par with HVAC lines:

A big part of the cost of having DC line is the high efficiency and high voltage power converters to transfer from AC-DC-AC, which you need regardless where the location is.

And no, you can't get arc that's 5 miles long, that would be quite a sight though. :)

Comment Re:Modify the phase variance (Score 1) 332

What insulation are you talking about? HVAC transmission aren't insulated at all. The advantage of AC over DC is that you don't need high efficiency high voltage power converters, which are very expensive compare to transformers. This is changing with advances in power electronics, but it's still more expensive than regular transformers.

HVDC is actually cheaper than HVAC on a per mile basis, but the power converters you need at the terminal brings up the cost. So for really long transmission, it starts to be more cost effective to use HVDC. One example is the HVDC on the west coast of US.

Comment Re:blackouts (Score 2, Informative) 332

That's simply not true. The grid operates with accordance to guidelines set by the North American Electricity Reliability Commission (NERC), one of the policy is something called "N-1 Criterion". Which means any one single transmission line or generation unit can go down without affecting the grid. And NERC also requires that the operator balance the grid to satisfy N-1 criterion after one contingency happens. So it's not like once one unit trips, another unit trip would destroy the grid. Yes, balancing the grid after a contingency takes time, but the likely hood of 2 events happen so closely is low. Plus, the N-1 Criterion requires the grid to remain stable for the single WORST scenario, which many contingencies aren't.

The cause of the August 2003 blackout also was caused by improper procedure by FirstEnergy, along with lack of situational awareness on the grid. The joint task force report on the blackout concluded the blackout could have and should have been prevented by proper operating procedure. You can find the link to it at the bottom of that wiki page you linked to, or here:

Yes, electricity travels fast, but that doesn't mean the grid is not operated to handle failures. BTW, this is my current research area, so I know at least a little bit of what I'm talking about. Not to make the logical fallacy of appealing to authority or anything.

Data Storage

How To Store Internal Hard Drives? 393

mike writes "I have been ripping all my movies and TV shows for easy viewing through a media PC. Because I would rather not rip everything again I'm looking for a simple backup solution. I'm considering a hard drive dock and several internal hard drives to use as 'disks' to back things up every once in a while but I don't know what the best way to store internal drives would be in the meantime. Could they sit together in any empty box and be OK, or would a number of externals be worth the slightly higher cost with fewer worries about storing them in the meantime?"

Comment Re:Plus, electrical demand is != bandwidth demand. (Score 1) 222

I think there's still some benefit to making the residential customers paying the true cost of electricity. True, not everyone will change their behaviour, but some might try to do their laundry during off peak hours. The cumulative effect might or might be big enough to make a difference. However, even if it's not big enough, at least utilities get a bit more money, which is in desperate need to upgrade the ancient infrastructure we have.

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