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User: WolfWithoutAClause

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  1. Re: What? "We're sorry we got caught"? on Volkswagen CEO Issues Apology Over Emission-Cheating Software · · Score: 1, Insightful

    You will almost certainly not achieve that, you'll get closer than you would in America- it helps a lot that European gallons are 1/3 bigger.

  2. Re:"It would likely cost quite a lot of money ..." on Club Concorde Wants To Put a Concorde Back In the Air · · Score: 1

    Specifically, it was 5K for going east. For going west you could get a ticket for £800 or so.

    The main reason it existed was to avoid the red eye; landing in the early morning at Heathrow is unbelievably horrible. Concorde avoided that.

  3. Re:Of course on How Wind and Politics Pushed the Price of Texas Electricity Below Zero · · Score: 1

    Depends what you mean by "experimental". If you mean whole communities and countries using renewable energy solely for their electric power then there's a list of those that already do that, and many have done for quite a long while:

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

  4. LOL, liquid (actually supercritical) CO2 is used to make decaffeinated coffee.

    Just because it sublimes, doesn't mean it doesn't have a liquid phase.

  5. Re:A good use for hydrogen on Proposed Lapcat II Hypersonic Airliner: Brussels to Sydney in Less Than 3 Hours · · Score: 1

    Nah, it's fairly practical, you just end up with a big aircraft. The only real problem is finding a big enough runway. Similar problems with the A380 faced.

    There's also cost, it's not a cheap fuel; but on the upside it has twice the energy per unit weight and it's a marvellous coolant.

  6. Re:A good use for hydrogen on Proposed Lapcat II Hypersonic Airliner: Brussels to Sydney in Less Than 3 Hours · · Score: 1

    Not sure about the Mach 8 version, but the Mach 5 LAPCAT A2 has extraclever turbofan engines, so should be quite quiet and efficient subsonically, and then when they're out over the ocean, they can turn it up to 11 and go Mach 5.

  7. Re:Funny you mention that... on Genes and Ancient Remedies May Help Fight Antibiotic Resistance · · Score: 2

    Um, unless you have a hole in your eardrum, that doesn't work; or at least it cannot work by disinfection.

    Peroxide in your ear can help get rid of earwax, but the kind of earache you get that needs antibiotics is on the other side of the eardrum, which is sealed from that side.

    Unless the earwax was building up to the point it blocked your Eustachian tube or unless the tickling on your eardrum cleared your Eustachian tube then it could just be a coincidence.

  8. Re:It's simple... on Slowing Wind Energy Production Suffers From Lack of Wind · · Score: 1

    Actually, you can change nuclear power pretty quickly (provided you don't want a complete shutdown) you just shove the rods in a bit and it cools down quite rapidly.

    The problem is that it just makes the electricity more expensive when you do that; when you run at 80% power, the energy is 20% more expensive, and it wasn't cheap to start with.

  9. Re:Not quite ready on Slowing Wind Energy Production Suffers From Lack of Wind · · Score: 1

    They're called 'peaker plants'. They're inefficient hydrocarbon plants that are relatively cheap to build that kick in when all else fails.

    But not all places need them. For example, if there's hydroelectric dams nearby you can just vary the hydroelectric output; it doesn't use any more water, it averages out.

    Denmark for example is on 40% wind power right now; they use Norway's hydro to even out their power. Norway doesn't on average supply them any power; but at any instant, Denmark will be powering them, or they will be powering Norway.

    Other schemes also work; having some biofuel around also helps, or batteries or pumped hydroelectric etc. etc.

    There's lots of ways to skin this cat.

  10. Re:meanwhile solar output from the sun was stable on Slowing Wind Energy Production Suffers From Lack of Wind · · Score: 1

    Still, people use less energy at night, so PVs aren't as silly as they look.

  11. Re:It's simple... on Slowing Wind Energy Production Suffers From Lack of Wind · · Score: 2

    Actually nuclear energy is more expensive than wind, and the lead times on nuclear reactors are huge, whereas wind turbines can be put up in a few years at most.

    Wind is not a direct replacement for nuclear, but it mostly doesn't matter. Also, variable power sources don't mesh well with nuclear reactors; nuclear reactors are expensive infrastructure, and have to be run flat out to be cost effective.

    For these reasons, as well as others, we're unlikely to see large widespread deployments of nuclear reactors any time soon, and renewables can be expected to continue to grow exponentially for perhaps a decade or so.

  12. Re:Not even close... on Plunging Battery Prices Expected To Spur Renewable Energy Adoption · · Score: 1

    Turns out that the battery price is dropping at about 8% per annum right now, and also the price paid for a battery depends on battery quantity- Nissan and Tesla pay less for their batteries than other manufacturers because they buy so many of them.

  13. Re:More batteries = more polution on Plunging Battery Prices Expected To Spur Renewable Energy Adoption · · Score: 1

    I hope you never drive anywhere either, because gasoline has a significantly higher risk profile per mile than lithium ion batteries.

  14. Re:Still a bad value on Plunging Battery Prices Expected To Spur Renewable Energy Adoption · · Score: 1

    Lithium ions still have a shelf life even with optimal use.

    There's essentially a form of corrosion going on inside the lithium ion pack, and after 5-10 years (depending on how it's stored and the pack's chemistry) it loses about 25% capacity, and the loss of capacity gets much faster after that.

    It helps to keep the pack at lower charge, and not permit it getting too hot, and not charging or discharging it too rapidly, but it still happens.

  15. Afghanistan is always a massive problem; it's not the external forces so much, it's more that it's so heavily tribal, and you don't know who is on your side, and that can vary. If somebody is identified as an islamist of some kind by an informant, chances are it's just another tribe settling a score. And later, did they just bomb you because they're terrorists, or because you just shot somebody who was on their side???

    Outsiders never quite know what's going on, and the Afghanis don't want you there anyway, because you're invading their country. Stir in lots of Afghani fighters with a reckless, fatalistic streak and... you're gonna have a hard time.

  16. Re:Fuck precious metals- propellant all the way ba on John S. Lewis On the Space Commodities Market · · Score: 1

    Yes, steam rockets, delta-v is a bit marginal though, ion drives might be better for the return to earth burn for the propellant.

    And actually, space elevators are extremely easy on Ceres, you can even build looped elevators that can lift stuff up into orbit. You don't need anything special, just some pulleys, long rope or metal cables, no carbon anything is needed.

  17. Re:Fuck precious metals- propellant all the way ba on John S. Lewis On the Space Commodities Market · · Score: 2

    NEOs can have much lower deltav but have much worse Synodic periods. That's because the orbital periods are similar, and they take longer to line up each time. And for a near Hohmann transfer which most travel is likely to use, they have to line up.

    So opportunities to travel there or back are few and far between. This makes them surprisingly useless as a propellant source, because unless the mining operation is unreasonably quick to perform, for orbital mechanics reasons you have to wait for multiple synodic periods before you return anything, and another one again before you can do it again. For example, if the synodic period is 5 years it could take 15-20 years to get your first shipment.

    Ceres is further out, but its synodic period is only 466 days; so you end up with a propellant shipment every 466 days.

    Getting to Ceres initially with mining gear is harder but a penalty that you only have to pay once, and you can use ion drives which can have high exhaust and deltav for that, but once you're returning propellant, you have the propellant you need to send further stuff to Ceres from Earth, and Earth to Ceres, so, although the deltav is the same each time, the effects of the delta-v penalty aren't quite so severe and you can set up cyclers to make the trip repeatedly at lower delta-v, and use aerobraking at Earth for the propellant.

    The other thing is that Ceres is outside the snow line; most NEOs have probably been baked out of volatiles on their surface, so mining them is much harder. Ceres is further out, so ice evaporates very slowly.

    All in all, Ceres looks like a much better bet all round.

  18. Fuck precious metals- propellant all the way baby on John S. Lewis On the Space Commodities Market · · Score: 2

    The thing is, to do anything in space you need propellant. Launching it from the ground is a mugs game; it costs ~$1000 per kg to get it even to LEO, even more to higher orbits.

    No, if you can mine propellant, then you can get ROI on any propellant you can return to LEO (or higher orbits).

    The thing is, we know for pretty high probability that (for example) Ceres has huge deposits of water.

    You can split water into hydrogen and oxygen, and use that for propellant. Once you have propellant you can set up cyclers that take about 15 months to deliver a load to LEO, and then go back and get some more. The amount you return each time can potentially grow exponentially each time, because you're using propellant to deliver propellant/"mining" equipment.

    The thing about Ceres, it looks like there's ice volcanos there, so "mining" water may be as simple as putting a funnel over the stream coming off Ceres, and bring it to a halt and pumping it into a tank. You can then use some of the water to send the rest of the water back towards Earth.

    And water in LEO is TREMENDOUSLY useful. Want to go to the moon? You need propellant to go there. Want to go to Mars? You need propellant and radiation shielding. Guess what- what is brilliant radiation shield as well.

    I'm not against other types of mining; but propellant mining is the one that all the other things rely on- it's the equivalent of oil in space.

  19. Re:This will be tricky. on The Lingering Effects of Ebola · · Score: 2

    The virus has been shown to be capable of hanging around in peoples eyes for weeks after they've otherwise recovered, (where it's NOT contagious unless their eyes gets mushed) and some of the patients have subsequently developed eye problems/blindness presumably because of this.

  20. Re:Fine but they should invest in wind next on Japan To Restart Nuclear Power Tomorrow After Energy Prices Soar · · Score: 1

    You can do conventional farming almost everywhere in a wind turbine farm.

    Wind power uses very little space, only a small footprint for the tower, and maybe a road; just a few percent of area is lost,

    Backup usually only starts to be a problem with very large wind power penetration percentages. If you're below 20% (which is much more than nuclear's penetration in most places), it's largely a non issue, and even 30% shows only modest increases in costs (n.b. Japan was on 30% nuclear power). Basically, the rest of the grid is typically flexible enough to ramp up and down as necessary.

    And note that nuclear has issues with variations; but not as the weather varies, as the demand side varies, nuclear doesn't usually demand follow; since nuclear power gets expensive when run at partial power, because it's costs are virtually all infrastructure costs.

    And no, Japan has very few wind turbines right now, only a couple of gigawatts or so. The UK has 14 GW and it's a significantly smaller country.

  21. Re:Fine but they should invest in wind next on Japan To Restart Nuclear Power Tomorrow After Energy Prices Soar · · Score: 1

    Nah. A fiscal policy that involves spending money in a recession often helps because the spent money is people's wages and they mostly spend it right back into the economy where it circulates, and some of it ends up helping repay the debt that is depressing demand. It also helps because any inflation created reduces nominal debt that is holding back the demand side.

  22. Re:Fine but they should invest in wind next on Japan To Restart Nuclear Power Tomorrow After Energy Prices Soar · · Score: 1

    They should be immune, the size of a tsumami is lot lower out at sea and they'd likely to be strong enough to take the impact anyway if they can take high winds. So far as I know, fixed things like bridges didn't get swept away, even on land, it's more fragile things like houses and cars and people that couldn't take it.

  23. Re:Fine but they should invest in wind next on Japan To Restart Nuclear Power Tomorrow After Energy Prices Soar · · Score: 1

    Doing it would doubtless help Japan's economy- a big infrastructure project is always good in a recession.

  24. Re:Fine but they should invest in wind next on Japan To Restart Nuclear Power Tomorrow After Energy Prices Soar · · Score: 2

    Things still fail, shit still happens.

    Yesterday I saw a picture where corrosion had eaten about 7 inches into a huge thick piece of metal in a reactor; but I can't find it today. Really scary.

    People make mistakes, in specifying, designing, building and operating equipment; even with things a lot less complicated than a nuclear reactor.

    The difference is, with other things, you don't have to evacuate towns (or entire CITIES) for hundreds of years when they fuck up.

  25. Re:Fine but they should invest in wind next on Japan To Restart Nuclear Power Tomorrow After Energy Prices Soar · · Score: 1

    There's over 600 GW of potential on and off-shore wind power around Japan, the normal average capacity factor with wind is at least 25%; often 35%. In other words there's enough wind power to power the entire country, just with wind power, at least on average. (For reference, the peak electricity demand in Japan is around 160GW during the summer.)

    https://en.wikipedia.org/w/ind...

    If you add some solar, and the existing hydroelectric then there's more than enough power and energy right there.

    And imports are a non issue with solar and wind.