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Comment Re:Stop Now (Score 1) 174

"End all involvement. This is a massive and pointless waste of money. It will never lead to any practical source of energy."
"I'm so glad you're smarter than all the scientists working on it."

Maybe he is, maybe he isn't. But he's still right.

There are two definitions of "working" one needs to consider. One is "this device fulfills a minimum technical requirement". The other is "this devices works, and is economically attractive". It is very clear to everyone involved, including "the scientists working on it", that ITER-like devices will almost certainly never fulfill the second of those two definitions.

I don't say this idly. I know some of the scientists working in fusion personally, I've written to and had conversations with a number of others. I've distilled the information down into the majority of the articles you'e read on the topic on the Wikipedia. I have a good overview level of the technology, and more critically, the other technologies fusion completes with. So I can speak with a good level of authority on this topic.

It's that (second) lash point that's important. If fusion were, as someone in this thread put it, "the only solution" to our energy problems, then the two definitions become one. As soon as it works, you start building them. But it's *not* the only form of energy that can solve "all our problems". And those solutions already work, and more importantly, will cost less than fusion of the ITER (or NIF) ever could. Period.

Even if ITER works, and even if there is a follow-on device that works better, there is, in theory, no way to make it cheap enough to compete with existing devices. For instance, on often sees the complaint that solar can't be the solution to our problems because the sun doesn't shine at night. Well actually it does, it just does it somewhere else. It will cost less to build enough panels to power everything AND a HVDC network to spread it around the world than it would to get the same power from fusion.

But don't take my word for it. Here's the word of *the guy that ran the US fusion program*:

First, we have to recognize that practical fusion power must measure up to or be superior to the competition in the electric power industry. Second, it is virtually certain that tokamak fusion as represented by ITER will not be practical.

If you want to know *why* this is, go here:

http://matter2energy.wordpress.com/2012/10/26/why-fusion-will-never-happen/

Comment Re:I'm playing the world's smallest violin (Score 1) 469

"However, even elite violinists cannot tell a Stradivarius from a top-quality modern violin, a new double-blind study suggests"

Is anyone really surprised to hear this?

"Antonio Stradivarius and his shop built wonderful instruments that probably played like 2x4s when new"

I suspect you would fail the same double-blind test, today, then, or in 100 years.

People convince themselves "they can tell the difference" when they can't. They've been doing it for all of history. Here is the canonical example:

https://en.wikipedia.org/wiki/N_ray

Comment Who cares? (Score 1) 470

"By incorporating examples of pseudoscience into lectures, instructors can provide students with the tools needed to understand the difference between scientific and pseudoscientific or paranormal claims"

Everyone already has all the tools they need to separate "real" from "pseudo" science. It's not that they can't, they just won't.

People who want to believe in this stuff believe in this stuff. It's not a lack of understanding or intellect, they simply want to (or not to) believe.

Comment Robot vision (Score 1) 496

I'm surprised how low-tech these solutions are. They appear to be going for the "classic solution" of simply piping a camera's view to a screen, perhaps with some overlays.

I recall seeing a demo many years ago of a robot vision system. If you're not familiar with the term, it uses a number of low-res cameras (all cameras were when the demo was made) pointing in different directions, and fused the imagery together in 3D software to produce a view from any location looking at any location. The idea was to put these in armoured vehicles and allow the guys inside to look anywhere.

This seems like a much better solution here. Instead of simply replacing the mirror with a high-def camera, replace it with a dozen VGA cameras around the car. Fuse the imagery back together and then overlay it on a 3D model of the car as seen from above. Now you get a birds-eye view from the front looking down showing you all the traffic in the area.

Comment Re:Cents per Watt (Score 5, Informative) 79

> Can someone who understands the subject matter better than I do please explain
> to me how "cents per watt" is an applicable comparative metric for fossil fuels and solar cells

The price of electricity is basically the total money you put into running the plant over its lifetime divided by the total amount of power you get out of it during that lifetime. That's called the "levelized cost of electricity" or LCoE.

For plants that don't use fuel - wind, hydro, PV - the total amount of money is basically the price of the plant, the price of repairs and operations, and the price of borrowing the money to pay for the first two. For systems that go up in a short time, like wind and PV, the costs are utterly dominated by the price of the equipment.

For other sources the total cost of operations varies. Nuclear plants use fuel, but so little of it that it's not a major factor. However, these plants have enormous up front costs and decades long building cycles, so their LCoE tends to be utterly dominated by the prevailing interest rate. Coal and natural gas plants cost about 1/4 that of a nuclear plant and are therefore more heavily dominated by fuel costs, so their cost of operations goes up and down with the cost of the fuel.

So when you're trying to compare the price of a PV plant to a coal plant, for instance, the key metric in the case of PV is the cost of the panels. That's because there's no fuel cost and almost zero maintenance (had mine 5 years, done exactly $0 work on them so far).

Since the amount of sunlight shining in a particular area is averaged over long periods and available online, you can then predict the amount of power the plant will produce over its lifetime. For instance, in Toronto 1000 W worth of panels (i.e., a set of panels that will produce 1000 watts under specific conditions) will produce about 1200 kWh of power every year, after all conversion losses are factored in. We expect those panels to last about 25 years. So then

LCoE = (cost in cents/watt * size of system in watts) / (25 years * 1200 kWh * system size in KILOwatts)

So let's say the system, *all in*, costs you $3.50 a watt (about right these days). Then if you put up a system with 12 panels like mine, you get

LCoE = (3.50 * 3000) / (25 * 1200 * 3) = 11.66 cents/kWh

I think you'll find that is very comparable to what you are paying from your local utility, which is why PV is the fastest growing power source in the world today.

This same basic formula can be used with any power source, but the inputs will differ. For instance, the equivalent number for a nuclear power plant is about 7500 to 8000 kWh per kW of panels installed, because they run full out 24/7, or at apt 85% full power, or "capacity factor". But as you might expect, construction costs are much higher, about $8/W or more (that plant in Florida came in at about $11/W, which is why they cancelled it).

Likewise, wind turbines here in Ontario average about 30% "capacity factor" (CF), so that's about 2600 kWh/kW. That sounds bad until you consider they cost about $2/W installed. So when you compare the two head up it's something like (2 / 0.3) = 6.66 for wind vs. (8 / 0.85) = 9.41 for nuclear, which is why wind is the second fastest growing power source on the planet.

And that's why we measure everything in terms of cents per watt. If you know that (although dollars per watt is the typical figure) and the capacity factor, everything else sort of disappears. So you can get a *very* good idea of the economics simply by dividing the ($/W) by (CF).

If you'd like to do this on your own, with real numbers and more factors, you can. It's actually very easy and you can run through a given location in about 2 minutes:

http://matter2energy.wordpress.com/2012/05/21/green-apples/

Comment Re:Yay! (Score 1) 125

> You can never have a monopoly on a web page

Balogna. Google has content that they have captured both themselves and from other people that they use to feed their search results. Examples include AdWords, Books and YouTube. Since those two already exist, and block competitors from getting the data, you will find it very difficult to make a search engine that comes anywhere near as close to being as good. You'll have access to public works, but not the private ones that Google has swallowed.

Comment So this is a bad why? (Score 3, Insightful) 259

"1996. The first reports of root worm resistance were officially documented in 2011"

So we got 15 years of pesticide-free corn? And the downside is we have to return to what we used to do, until we get another variety?

If it's 15 years for that one too, I suspect we can out engineer the bugs continually.

Comment Re:fusion is expensive (Score 1) 196

> Who's to say that eventually, reactors will be built that not only work economically, but even cheaply?

Basically anyone that's not in the fusion industry. You know, like nuclear bomb designers:

Lawrence E Lidsky, ‘The Trouble With Fusion’, Technology Review Vol. 86 October, 1983. Pages 32-44.

Or large scientific groups:

Allen L Hammond, William D Metz, and Thomas H Maugh II, ‘Energy and the Future’ Washington DC, American Association for the Advancement of Science, 1973.

Or the entire US power industry:

http://fire.pppl.gov/EPRI_Fusion_Criteria_1994.pdf

Or even supporters of other versions of fusion:

http://dotearth.blogs.nytimes.com/2012/10/19/a-veteran-of-fusion-science-proposes-narrowing-the-field/?_php=true&_type=blogs&_r=0

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