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Mining Companies Are Using Autonomous Trucks, Drills and Trains To Boost Efficiency, Reduce Employees ( 94

schwit1 quotes a report from MIT Technology Review: Mining companies are rolling out autonomous trucks, drills, and trains, which will boost efficiency but also reduce the need for human employees. Rio Tinto uses driverless trucks provided by Japan's Komatsu. They find their way around using precision GPS and look out for obstacles using radar and laser sensors. The company's driverless trucks have proven to be roughly 15 percent cheaper to run than vehicles with humans behind the wheel -- a significant saving since haulage is by far a mine's largest operational cost. Trucks that drive themselves can spend more time working because software doesn't need to stop for shift changes or bathroom breaks. They are also more predictable in how they do things like pull up for loading. "All those places where you could lose a few seconds or minutes by not being consistent add up," says Rob Atkinson, who leads productivity efforts at Rio Tinto. They also improve safety. The driverless locomotives, due to be tested extensively next year and fully deployed by 2018, are expected to bring similar benefits. They also anticipate savings on train maintenance, because software can be more predictable and gentle than any human in how it uses brakes and other controls. Diggers and bulldozers could be next to be automated.

Comment Re: not quite correct (Score 1) 257

> There is nothing you can do with it today you can't do faster with native code

Which is not the point of the product, at all.

The only point of this effort is to allow you to use your existing .Net code on other platforms. It does that fairly well.

Other *really* means iOS and Android. I have used the iOS version and it does what it is supposed to, building apps that use native UI with our .Net business logic below. I don't know if the Android version is as good, but I can't imagine why it would not be.

Comment Re:Solar now competitive with coal and gas? (Score 4, Interesting) 220

There are lots of places in the world that are not the US, and don;'t have the same subsidy system you have. Wind and PV are doing even better there, mostly because they don't have entrenched billionaires like the Koch brothers spending millions of dollars to convince you it's all a plot.

Comment Re:Any thoughts on Thorium? (Score 0) 220

> Thorium seems like it might be viable alternative.


I just got the numbers from the World Nuclear Association a few days ago, from their last major report circa 2013. The "nuclear island" part of a reactor design is a little under 30% of the cost of the plant as a whole.

A modern plant like the AP-1000 costs about $7.60/Wp CAPEX. That means the rest of the plant is about $5.30. So the absolute minimum cost for a thorium plant, assuming the reactor costs zero dollars, is $5.30.

A wind turbine, complete and fully commissioned, costs about $1.50/Wp CAPEX. Now there's a difference in CF, but that's easily accounted for. Modern large (~2.5MWp) turbines have CF around 35%, while a modern nuclear plant is about 90%. So...

5.30 / .9 = 5.88
1.50 / .35 = 4.28

In other words, wind is ~30% cheaper than thorium even if you don't actually build the reactor.

Tell me how that is going to compete 20 years from now after wind costs continue to fall every year.

Comment Re:Great for 10% of the population (Score 2) 220

> the frequencies blocked by the clouds are not the ones that PV cells are most efficient at collecting.

Uhhh, yes they are. PV is most efficient in red, and clouds block that just fine.

My panels have been going for six years now, they show a pretty much linear production with cloud percentage.

The temperature effects you note are minor in comparison, I can't even see them on my production charts, except for gross seasonable time frames.

Comment Re:A confused article (Score 4, Insightful) 220

> Wouldn't it make more sense to

Ah yes, the "makes sense" clause, which in this case means "I have no clue but I'm going to post anyway".

> shut the turbine down and spare the maintenance?

No. The marginal production cost for wind is close to zero. As opposed to, say,a gas plant, where even at idle you're still burning fuel. This has been *repeatedly* covered here on Ars.

> The answer is the subsidies.

Maybe it's different in Texas, but everywhere I'm familiar with the subsidies are in the form of tax credits and are on the order of 20% of the LCoE. In comparison, something like the nuclear industry receives about 10 times that amount of money, all of it up-front, and still isn't competitive,

Why is anyone surprised by this? A wind turbine is a generator, which all plants have, some blades, a steel pole, and a concrete base. Of course that is going to be able to compete once the learning curve kicks in. PV is even simpler, it's basically a storm window with some wiring. It doesn't even have moving parts. On a pure CAPEX basis there's no way anyone can compete.

Comment Re:Cheaper than wind? (Score 4, Informative) 220

> Frequently they underestimate owner's costs and T&D in these comparisons and only look at simplistic
> models of construction labor/material and fuel costs

Fuel costs... for solar?

> I can tell you that natural gas combined cycle plants are still far cheaper to build and run than solar or wind.

They simply are not. They are certainly competitive, but in the last two years or so the CAPEX side for PV and wind has been plummeting. Here's a reasonably up-to-date listing:

Look on page 11.

Comment Re:Deiterium-Tritisum Fusion no good for power (Score 1) 431

> The only currently feasible ... is solar sails

I think you need to look up the definition of feasible. It does not include "that thing that we have never successfully deployed even at the scale of a pocket square", nor "spend billions of dollars to get something we can scoop up off a dry lake in Bolivia".

> colleague gave me recently

You work in the comic book industry?

Comment Re:Reads Like An Ad (Score 1) 431

> if we'd kept funding at the anticipated rate in the '60s, we might have working fusion already

This canard gets passed around in every thread on the topic. It is wrong. Period.

The prediction in question was made in the 1970s when everyone was *absolutely sure* that the latest generation of designs would reach break even. These included, among others, MFTR and TFTR. The prediction, then, was that by developing production versions of these designs one would have a commercial machine, and you could make reasonable predictions on how much those would cost to develop.

Except when they turned on TFTR, it didn't work. Instead, it exposed another group of previously unexpected problems. Some of these also applied to MFTR, which was then shut down shortly after (physical) completion. At that point it was clear that neither was a pattern for a commercial machine, and no one had any idea how much it would cost to fix it, let alone develop a commercial model from those fixes.

ITER represents those fixes. The answer, then, is that it costs about 25 times as much as TFTR to get a machine that produces the results TFTR was supposed to - and that's assuming ITER doesn't fail. Applying the same scaling factors to ITER that they applied to TFTR means the production machines will cost on the order of hundreds of billions to develop.

Meanwhile, in the last few decades the PV researchers, working on perhaps 1/100th the amount of investment, decreased the cost of PV about 200 times. If installed in sunny locations, like Nevada, it produces power for about 4 cents, making it (inflation adjusted) one of the cheapest forms of power in history. When faced with this reality, fusion supporters have retreated to various arguments about why you can't possibly use these sources for X and Y, in spite of people already using them for X and Y all over the world.

Comment Re:Top 3 promising fusion concepts: (Score 1) 431

> Focus fusion and Polywell are also promising

No they aren't. All modern pathways look promising until they tried to scale them up. And both of these are subject to the non-equilibrium braking radiation problem, which appears insurmountable.

> but underfunded

The problems with fusion cannot be solved by throwing money at that, that makes the problem *worse*. The problem is not actually physics, its economics, and we already know fusion is not competitive.

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