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Comment Re:Supplant Niche (Score 1) 66

Disagree. A good car doesn't have down force (beyond gravity), downforce means aerodynamic drag, a good car should rely only on the force of gravity for its grip. The things that help a plane also make a car more fuel efficient - streamlining and lightweight construction. Cars have slightly different streamlining reqs due to operating near the ground, but the general principles are the same. Of course you've got wheels out there, but so do many light planes. Lightweight construction is often described as the opposite of crash safety, which is very important in cars, but with foam core composites you can have both.

As for the GP's comments: I don't think anyone really expects your average driver of a flying car to be behind the stick controlling flight surfaces; I think most people envision something more like a good quadcopter where everything is managed for you by control software that maintains position and attitude (despite changes in balance, wind, etc) or even fly preset routes / automated traffic management. People don't envision runways, they envision VTOL. They envision not a helicopter (non-roadworthy, giant exposed spinning prop), but something roadworthy with nacelles.

One big former problem with flying cars was the weight, size, cost and complexity of the sort of high power engines you needed for them, and if you needed multiple engines (quadcopter-style), then all the more problem. It pretty much ensured that your flying car would have a supercar price tag. But electrification of transportation looks to be solving that one - high power outrunner electric motors are very simple and have just ridiculous power to weight ratios. Battery energy density is still a problem (and would be even more of a problem if your lifting surface area is limited and you lose a little efficiency to your prop geometry), but it's constantly improving, the percentage rate of growth on electric passenger airplanes is even faster than that of electric cars (although starting from a much smaller starting point, mind you).

No, I'm not saying I envision the world suddenly switching over to flying cars - far from it. I'm just pointing out that the problems aren't as intractable as folk often make them out to be.

Comment Re:The Discovery channel? (Score 4, Insightful) 103

Both are terrible, and started going downhill around the same time, racing each other to the bottom - beginning in 2005 (when you started getting shows like Deadliest Catch and Decoding the Past, which became the prototype for many future series of increasingly less "reality"), and then full force by 2007 where you start getting too many shows to name.

One thing that drives me crazy almost as much as the blatant pseudoscience presented as fact is the extensive acting presented as reality. I mean, okay, I get it, a purely "reality" program is pretty much impossible, the very requirements of filming it make it so. Even in stuff like Les Stroud's "solo" work he always had a base camp just a couple kilometers away from him and stayed in communication with them by radio. But now the stage guidance, product promotion, and "weekly scripted adventures" have gotten so absurd and obvious, they don't even try to hide it any more. I thought that they couldn't get any lower than the bogus survival show Man vs. Wild (where the host pretended to be living in homemade shelters and surviving off wild food, when he was actually staying in luxury hotels and show consultants prepped everything from making "rafts" for him to releasing "wild" animals for him to catch). But now almost all of their shows are like that or even worse. And the product promotion, my god - have you seen the Pawn Stars plugging for Skype? If you're going to have your "reality show" stars plug a product in your show, at least get people who can act.

The changes are so visible with time, too. Take Mythbusters for example - watch some of the early eps and compare with the modern eps and look at how much more is obviously staged acting with everyone reciting a script (not to the extent of Smash Labs, but still). Apparently Discovery Communications has decided that this is what people want to see - bad actors going on "daily adventures" and having "witty banter".

Comment Re:not big in UK (Score 2, Insightful) 120

My BS detector went off when I saw that graph, so I had to actually read the paper... and now I understand the graph and it's not at all what it seems to be.

See that giant circle for silver? That doesn't mean "a massive amount of silver", or even "a massive amount of environmental impact from silver". These circles are sized proportionally to how much more of a resource is needed than in the current generation mix, if all power came from that source. Since almost no silver is used in the current generation mix, anything that actually uses silver - even if a rather small amount - will dramatically inflate its circle.

In all of the study's graphs, the amount of silver used is so small that the bars don't even register one pixel tall, so you can't really estimate how much they're talking about. The only graph where you see any height at all, Fig 8, is the graph relative to total world production - but even in their highest scenario it's less than 0.5% of world production. And the study itself notes, "Silver in PV cells might be replaced by other metals". Silver has only a 6% better conductivity than copper, it's not a big difference. And if you're willing to use slightly thicker or more frequent connects, you can use cheap and hyper-abundant aluminum. Either way, the amount of metal involved is practically irrelevant, the interconnects we're talking about here are practically microscopic.

Comment Re:Small-scale, real-time. (Score 4, Insightful) 502

Um, yeah, I don't believe you for even a quarter second.

1. Nobody who runs a wind farm would refer to wind turbines as "windmills". Seriously, that's like a third-grade level mistake. This is a windmill. This is a wind turbine. Nobody in the industry would ever call a wind turbine a windmill, they'd get laughed at.

2. The typical bat in the US weighs about 10 grams. Even if we assume that the "trucks" are only pickup trucks that can haul 2 tonnes and your use of the plural only means two - about the lowest possible way we could interpret your "truckloads every year" comment - that would be 400 thousand bats per year. Your mere 700 commercial-scale wind turbines (less than 2% of the US total) would have long ago driven to local extinction any bats in your area.

The reality, of course, is that estimates for all bat deaths from wind turbines in the US combined range from about 30k per year to 800k per year. All combined.

3. Your "destroys the health of operators and technicians" line puts you solidly in autism-vaccine cookoo land.

Just ignoring your grossly inaccurate description of wind power availability, or the concept that a wind farm operator is going to hire someone who despises wind power with a red-hot passion to run their facility.

Comment Re:Don't be silly. (Score 1) 119

I actually totally get Amazon's logic on this one. If there's only a $10 extra profit on each drone delivery (something I'm sure tons of people in range of the service would pay for in order to get their item in half an hour), and if we assume each drone operational cycle takes one hour (delivery, return, charging), then that's $240 a day. Doesn't take a lot of days to justify the cost of a drone with a return like that.

Comment Re:Every month a new battery breakthrough, but.. (Score 5, Insightful) 119

Except that you have bought them; you just haven't realized it. Energy density of li-ion batteries has grown by about 50% in the past five years. Have you seriously not noticed how cell phone and laptop battery mah ratings keep growing while they keep making the volume available for the batteries smaller?

It's big news when a new tech happens in the lab. It's not big news when the cells first roll off a production line.

Most new lab techs don't make it to commercialization. But a lucky fraction of them do, and that's the reason that you're not walking around today with a cell phone with a battery the size of a small brick.

Comment Re:More Range Needed (Score 2) 119

If everyone last person was going to be driving electric cars tomorrow, yes, that would be a problem.

Given that that's not the case, and for decades it's always going to be such that the people whose situation best suits an electric car are going to be the next ones in line to adopt them, then no, it's not a problem. You really think people can't build curbside/parking lot charging stations over the course of *decades* if there seems to be steadily growing interest in EVs?

As a side note, I don't know those exact neighborhoods in your pictures, but in my experience, most people who live in such places don't own *any* car.

Comment Re:More Range Needed (Score 1) 119

Actually, 800 is quite a sensible number. At an average speed of 60 miles per hour (aka, factoring in driving / bathroom / meal breaks), that's 13 1/2 hours of driving - a good day's drive. Throw in a few more hours driving time / a couple hundred miles more range if you charge while you're taking your breaks. Once you get that sort of range, charge speed becomes virtually irrelevant because it happens while you're sleeping (and getting ready for bed / getting up in the morning). A regular Tesla home charger could handle that sort of load.

I agree with you that a half hour charge isn't actually that onerous, but it definitely will scare off people who are used to filling up faster. And charge stations that can do half hour charges on 300 miles range (150kW+ for an efficient car, more like 250kW for a light truck) are exceedingly rare as it stands. A charger that powerful isn't some aren't some little wall box with a cord hanging off of it, it's the size of a couple soda machines put together (bigger if you add a battery buffer so that you don't need a huge power feed) that feeds so much power that its cable has to be liquid cooled and which costs around $100k installed. Ten minute charges are, of course, around three times that size. I've only ever come across mention of *one* charger in the ballpark of the required 750kW to charge a 300 mile light truck in 10 minutes - an 800kW device custom made a couple years back for the US Army Tank Command. I have no clue what it cost, but I'm guessing "Very Expensive".

I'm not saying that the problem is intractable, by any stretch, I totally believe that we're going to transition over to EVs. I just question the sort of time scales that a lot of people envision. The average car on US roads is 10 years old. Implying an average 20 year lifespan. And many cars don't get scrapped then, they just go to the third world. Even if you suddenly switch all new car manufacturing over to EVs, you're talking decades to replace them. But of course you can't just switch over like that - even if everyone was right now sold on the concept of EVs with current tech, you're talking at least a decade, possibly more, to tool up to that level of production. But of course, not everyone is right now sold on the concept of EVs with current tech.

Realistically, you're looking at maybe a 40 year transition. I hate to say that, because I love EVs, but I'm not going to just pretend that the reality is other than it is.

I'll also add that while fast chargers are big and expensive, the size and cost actually are comparable to building a gas station on a per-pump basis, and the economic argument works out for making them even if there's only a reasonable (50% or less) surcharge on the electricity sold and if they're only selling electricity a couple percent of the time. But you need to get a couple percent of the time usage to economically justify them - one person stopping for 10 minutes every few days just isn't going to cut it. And not every EV is going to stop at every charger even if they're driving on the same route - if your chargers are that far apart, then that means you're pushing people's range so much that they're not going to be comfortable driving that route. All together, this means that if you want to have fast charging infrastructure economically justifiable in an area you need high EV penetration, where several dozen EVs driving long distances will be going by each charger every day - even out in the boonies. And when you're talking at prices on the order of $100k per unit, you're no longer talking about a range where peoples' goodwill toward EVs or interest in having a loss leader outside is going to pay for them.

Basically, while busy interstate routes on the coasts and the like can economically justify them with a small fraction of a percent of people driving EVs, out in the boonies, they're going to be stuck with smaller, cheaper, slower chargers for a good while. Unless people are willing to pay a big surcharge on the electricity sold, that is (500% surcharge instead of 50% = 1/10th as many vehicles needed).

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