Slashdot Mirror


User: Guspaz

Guspaz's activity in the archive.

Stories
0
Comments
4,511
First seen
Last seen
Profile
(view on slashdot.org)

Comments · 4,511

  1. Wait, past cold war space race levels? on President Obama Calls For New 'Space Race' Funding · · Score: 1

    So, Obama wants to get NASA's budget higher than it was at the height of the space race? Presuming we're talking in inflation-adjusted dollars here (and not percentage of federal budget, because that would be nuts), that's an increase to about 2.1x the current budget.

    It seems to me that doubling NASA's budget is not terribly likely. America's chances of comprehensive space travel seem like they have little chance except through the dramatically lower cost of commercial spaceflight.

  2. No. on Could New York City Cut Emissions 90% By 2050? · · Score: 1

    If a headline asks a question, the answer is no.

  3. Re:Throwing money away on CES: Tiny Fuel Cell is Supposed to Charge a Cell Phone for Two Weeks (Video) · · Score: 1

    I'm presuming you'd have both the fuel cell and ICE powered by the same fuel (like butane)? If we use the Nissan Leaf as an example, and consider the EPA's estimates (we want the total time spent driving until battery exhaustion regardless of range), we see the following power usage scenarios (24 / num hours driving):

    Cruising (ideal): 6.6 kW
    City traffic: 5.5 kW
    Highway (with AC): 18.9 kW
    Winter stop and go (with heater): 5.8 kW
    Heavy stop and go (with AC): 3.1 kW

    As you can see, your idea of a 3 kW fuel cell could make a huge difference in range before the butane ICE would have to kick in. In most of those examples, the fuel cell would roughly double the range of the vehicle before it had to use the butane ICE, and in the heavy stop and go traffic, the ICE would never be needed before the battery ran down. Of course, I'm ignoring things like carrying around the extra weight, but you get the idea.

  4. Re:Small print on CES: Tiny Fuel Cell is Supposed to Charge a Cell Phone for Two Weeks (Video) · · Score: 1

    That butane portable generator looks like a terrible idea. Compare the equivalent power Yamaha EF1000iS gasoline generator to this new Honda butane generator:

    Size
    Butane: 1.78 cuft
    Gasoline: 1.45 cuft

    Weight (dry/full)
    Butane: 19.5 / 20.5 kg
    Gasoline: 12.7 / 14.5 kg

    Runtime (225w / 900 w)
    Butane: 2.2 / 1.1 hours
    Gasoline:12.0 / 4.3 hours

    Noise level in LWA (225w / 900w)
    Butane: 54 - 59
    Gasoline: 47 - 57

    Cost for 1 kWh of power at 225w (quarter load)
    Butane: 792 yen / 8.58 USD (4x TOHO butane cans based on 2.2 hour runtime at 225w per two internal canisters))
    Gasoline: 0.88 USD (4.4 hours of runtime using 0.926 litres of fuel at current average US gas price of 0.954 USD per litre)

    In other words, the Butane model is a bit bigger, a lot heavier, a lot louder, enormously more expensive, and has a tiny fraction of the runtime... A butane-powered 900 watt portable fuel cell would perhaps resolve many of these issues, but this Honda generator isn't a fuel cell. It's a non-competitive ICE generator.

  5. Re:Throwing money away on CES: Tiny Fuel Cell is Supposed to Charge a Cell Phone for Two Weeks (Video) · · Score: 1

    Well, the zombies might be attracted to the loud generator (even their decaying ears can hear something that loud), but fuel cells are much quieter ;)

  6. Re:Throwing money away on CES: Tiny Fuel Cell is Supposed to Charge a Cell Phone for Two Weeks (Video) · · Score: 1

    If you're going on some sort of a trip where you'll need to keep your phone charged for an extended period of time, it may not be feasible to carry enough lithium ion capacity with you. But those sorts of scenarios will be pretty rare. My IMP120D isn't exactly a lightweight at about a pound, but it'll recharge my smartphone several times over...

  7. Re:Throwing money away on CES: Tiny Fuel Cell is Supposed to Charge a Cell Phone for Two Weeks (Video) · · Score: 1

    To reply to myself with an example, consider military use. There are a lot of scenarios where you need a lot of electricity (powering soldier electronics, surveillance drone, robotics) where any kind of replenishment (be it charging or refueling) isn't feasible or practical. If using this sort of fuel cell system can let a drone stay up ten times longer or a robot operate ten times longer without having to resort to noisy gasoline engines, it might be pretty damned useful.

  8. Re:Throwing money away on CES: Tiny Fuel Cell is Supposed to Charge a Cell Phone for Two Weeks (Video) · · Score: 1

    If you need power density and cost is no object, the spare fuel pods for this Nectar thing have an enormously higher energy density than a lithium ion battery. The fuel pods in isolation get 1,570 Wh/kg while a lithium ion battery in isolation gets typically 150-200 Wh/kg. So you're talking about up to ten times the energy per weight as compared to lithium ion batteries. The cost is very high (prohibitively so for anyone who isn't rich), but there are certainly some situations where the weight is more important than the cost, and a ten fold increase in energy means that trade-off might matter.

  9. In terms of total energy density, the small fuel pod in the Nectar is waaay more energy dense than a comparable lithium ion battery. Considering that I've never seen a lithium ion battery ever actually explode (spark, catch fire, melt through tables, yes, but actually kaboom no), I'd argue that the butane pod would have a better "blast radius" if the conditions were right.

  10. Re:Vaporware? on CES: Tiny Fuel Cell is Supposed to Charge a Cell Phone for Two Weeks (Video) · · Score: 1

    Some googling shows the actual fuelcell will be $300. The energy capacity if you carry a bunch of spares is actually much better than a lithium ion battery, although the fact this thing can't even provide as much power as a normal USB port (2W vs 2.5W) is going to be a problem. This thing can charge a cellphone, but not while you're using the phone.

  11. Re:Small print on CES: Tiny Fuel Cell is Supposed to Charge a Cell Phone for Two Weeks (Video) · · Score: 2

    Yikes, I had written up a long reply comparing the density and cost to existing solutions and against the Horizon unit, and lost it all. Suffice it to say that the Nectar was about $490 to hit the first kilowatt, the NewTrent IMP120D battery was about $77, and the Horizon as (due to free refills) only $378.

    Also, the Nectar actually provided roughly double the power per weight or volume as compared to the lithium ion (a first for a fuel cell to do so well), while the Horizon was about even in weight and terrible in volume (the thing only provides 15 Wh, compared to 55 for the Nectar and 44.4 for the IMP120D).

    The Nectar is the first mobile fuel cell to actually be a better alternative than lithium ion. Everything else anybody has put out before (especially the Horizon thing) has been a laughable joke of a product.

    The only downside is cost. $10 per refill (which is what everybody reports, not the $20 Brookstone has) is incredibly expensive when compared to the half cent it would cost to recharge a lithium ion battery (based on HydroQuebec pricing, anyhow). The Nectar, despite its advantages, is only useful in two cases. Either you're rich, or you need to be able to carry a whole lot of refills with you.

    Ultimately, the low amount of power produced by the Nectar is a problem. Two watts is not even enough to provide the same amount of power as a regular USB 2 port (2.5W), let alone USB 3 (4.5W), and nowhere near enough to charge a tablet (10W). In fact, most modern cellphones need more power than a USB port can provide to charge at full speed, and an iPhone draws more power under full load than USB 2 can provide. So if an iPhone's battery will slowly drain under heavy use even while charging, the lesser power provided by the Nectar would be even worse.

    Still, for pure density, throwing a bunch of the pods in a backpack will beat out any competing solution, problems notwithstanding.

  12. Re:Yawn. on Surface Pro: 'Virtually Unrepairable' · · Score: 3, Informative

    Right, I was merely pointing out that while they made the thing impossible to maintain or upgrade (and how the hell are you supposed to get inside it to clear the dust off the fans/heatsinks?), they're using bog standard notebook components. A real tablet would have soldered the NAND chips to the motherboard. Heck, even the Mac Air have a custom form factor SSD in order to save space in the small chassis. The Surface Pro doesn't even do that, it has a full sized mSATA card in it.

  13. Re:Yawn. on Surface Pro: 'Virtually Unrepairable' · · Score: 1

    It should be pointed out that not only does the Surface Pro have an SSD, it has a standard form factor mSATA SSD, the kind you can buy at retail. The kind you even find in small form factor desktops like a Shuttle XPC.

  14. Re:Musk isn't doing himself any favors here on Elon Musk Lays Out His Evidence That NYT Tesla Test Drive Was Staged · · Score: 1

    You don't have to worry about getting stranded if you're not continually failing to charge your car and departing on 60 mile trips on a 30 mile charge. The point of pointing out the speed and the climate settings is that both of these activities (extra heating, extra speed) consume more power, and reduce range. By lying about these things, the author of the fake article was attempting to make the car look worse than it actually is.

  15. Re:1 Hour of Recharging every 200 miles? on Elon Musk Lays Out His Evidence That NYT Tesla Test Drive Was Staged · · Score: 1

    One hour on a super charger is supposed to completely top off the battery, although their claimed range is 300 miles rather than 200. Half an hour is supposed to get you 150 miles.

  16. Re:I'm a skeptic. on Elon Musk Lays Out His Evidence That NYT Tesla Test Drive Was Staged · · Score: 5, Informative

    So did Motor Trend... They named it their 2013 car of the year. As did Automobile Magazine.

  17. Re:Very very poor article on Intel Supports OpenGL ES 3.0 On Linux Before Windows · · Score: 1

    Sorry, I should clarify, the GPU is more than double the size of the GPU in any APU.

  18. Re:Very very poor article on Intel Supports OpenGL ES 3.0 On Linux Before Windows · · Score: 1

    The PS4's use of an APU is an unsubstantiated rumour at this point, the Wii U definitely doesn't use an AMD CPU at all (it's a PowerPC for Pete's sake), and the XBox 720's rumoured to have a GPU that's more than double the size of the biggest one they're shipping today (as far as I can tell), indicating a more traditional CPU/GPU architecture...

  19. Re:.3mm must be wrong. on CES: Formlabs Co-Founder Describes Their Stereolithographic 3D Printer (Video) · · Score: 2

    0.3mm is the dot size (minimum feature size). The equivalent measurement on the Makerbot Replicator 2 is 0.4mm. Both the Form 1 and he Replicator 2 can position the feature more precisely than that, but those measurements are how small the feature can be once positioned. Another relevant measure is the minimum layer thickness; 25 microns for the Form 1, 100 microns for the Replicator 2.

  20. Re:Very very poor article on Intel Supports OpenGL ES 3.0 On Linux Before Windows · · Score: 1

    Microsoft going AMD Fusion would be surprising, since the AMD Fusion chips that can compete with Haswell on a power usage standpoint make the Atom look high performance by comparison.

  21. Re:Why? on Intel Supports OpenGL ES 3.0 On Linux Before Windows · · Score: 4, Insightful

    On the other hand, if you're not the one writing the apps, it can be infuriating to use a system that supports only OpenGL ES. Last time I tried to use Ubuntu on a system with only OpenGL ES support, I discovered that OpenGL ES basically meant "no graphics acceleration", because nothing in the repository supported it; everything wanted OpenGL.

    That's probably changed since then (it was a few years ago), but it was pretty frustrating at the time, especially since the GPU itself was rated for full OpenGL, it was only that PowerVR charged extra for that driver and TI didn't want to license it.

  22. Re:The damage is already done. on Moving the Linux Kernel Console To User-Space · · Score: 1

    I'm not a system administrator... This is a home file server, and apparently you and everybody else is convinced that people who want to use home file servers need to build an enterprise-grade datacenter in their homes.

  23. Catching up? on GNU Hurd To Develop SATA, USB, Audio Support · · Score: 1

    Adding support for sound cards doesn't mean Hurd has caught up with anything but the mid to late 1980s. Both Mac and PCs had support for this sort of functionality in the 1980s (1984 for the first Mac, 1989 for the first Soundblaster).

  24. Re:So tablets at PCs now? on Apple Now the Top PC Vendor, For Some Values of PC · · Score: 1

    Ah, but in this case, it doesn't have any BIOS emulation, it's flat-up UEFI only. It only runs Windows because Windows was adapted to run without a traditional BIOS, not because the Mac was made to provide that functionality.

  25. Re:The damage is already done. on Moving the Linux Kernel Console To User-Space · · Score: 1

    Don't own any Android devices. Sorry.