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Comment don't call these offers. they aren't (Score 4, Insightful) 227

This article is about spam, not real offers. If they were real offers, it would give the lowdown-- location, skills, duties, and pay. It would be an actual employment contract, and all the candidate would have to do is sign up, or not.

So often, these so-called jobs are fake. There isn't a real job, they're just harvesting resumes. Or maybe there is but they've already settled on a candidate, and everyone else has no real chance, the employer is only going through the motions to satisfy EEOC rules.

Comment Re:'Hidden city' explanation (Score 2) 126

And the lawyers, who billed for the time filing the case. And the clients who, I suspect, worked with the lawyers to find the friendliest venue to file the case ina: a friendly venue can make an enormous difference in court cases. It's called "forum shopping", and it's a critical tactical factor.

Comment Re:Prior art (Score 1) 60

Unfortunately, their incentives are diametrically opposed to common sense. There is literally no downside for a USPTO examiner to rubber-stamp everything on his or her desk. They get to go home early to beat the traffic, while productive society is left to deal with the legal fallout. The net effect is to devalue legitimate IP while rewarding the trolls.

THIS IS WHY WE CAN'T HAVE NICE THINGS

It's because of this and copyright abuse that I think, sometimes, that we should just chuck it all and rely on trade secrets and a free-for-all on copyright. These jerks are not just poisoning the well, they're throwing dead goats in it.

--
BMO

Comment Where we need to get to call this real (Score 1) 480

Before we call this real, we need to put one on some object in orbit, leave it in continuous operation, and use it to raise the orbit by a measurable amount large enough that there would not be argument regarding where it came from. The Space Station would be just fine. It has power for experiments that is probably sufficient and it has a continuing problem of needing to raise its orbit.

And believe me, if this raises the orbit of the Space Station they aren't going to want to disconnect it after the experiment. We spend a tremendous amount of money to get additional Delta-V to that thing, and it comes down if we don't.

Comment Re:Can't wait to get this installed in my house (Score 1) 514

There's charging and discharging efficiencies to factor in too. You don't get as much energy out as you put into the battery - some of it gets converted to heat. Typically it's around 70%-80% (which would make the 5.5 years you calculated about 6-6.5 years), but it depends a lot on the battery tech, voltage, and charge rate. Better to wait and see what the real specs are.

On the flip side, if it works as advertised, expect to see utility subsidies for these. Time-shifting load from peak to off-peak means they can increase daily capacity without having to build new generation plants. So often it's more cost-effective for them to subsidize technologies like this rather than fund construction of a new plant.

Comment Re:Well... (Score 1) 108

With some optimism that might only be thousands of years rather than hundreds of Millions.

But it's only necessary for Earth to be uninhabitable for a short time to end the Human race. And that can happen due to man or nature, today. If people aren't somewhere else during that process, that's the end.

Comment Re:A glimpse into our future (Score 1) 67

there's a need for things like this so family who lives far away can still make sure parents are OK.

Actually, in Asia, elderly parents usually live with their kids. That something like this is needed is more a sign of the rising number of dual income households where the elderly parents are left home alone during the day.

California (which has a high Asian immigrant population who didn't budget for nursing home expenses) tried to tackle this with Adult Day Health Care - basically day care for the elderly. Your parents live at home, you drop them off at the ADHC during the day while you and your spouse work, and you pick them up when you get off work. But the program got sharply curtailed during the recent budget cuts.

Comment Re:Show me the math on the Tesla. (Score 1) 280

Show me the math for both ICE cars and Tesla, from well-head to road. Because generating electricity takes energy, and there are losses in the distribution system, and the charging systems are not 100% efficient either.

Sorry for the repost. This is probably a better place for this.

The 1100 BTU/mi figure is consistent with the efficiency of a ICE vehicle from crankshaft to wheels. It takes about 20-25 hp to push a ICE vehicle at 60 mph. So in an hour it will burn 53.7-67.1 MJ. Since it travels 60 miles in that hour, that works out to 0.89-1.12 MJ/mile. Or 848-1060 BTU/mile at highway speeds.

If you factor in other losses for the Tesla, add in a 40% efficient coal plant generating the electricity, 97% transmission efficiency over high-power electrical lines, and 75% charging efficiency and the Tesla actually uses 1100 / (.4*.97*.75) = 3780 BTU per vehicle mile. So it's actually not much different from an ICE from an energy consumption standpoint. (There are discharge losses too, but since the 1100 BTU/mi figure was apparently derived from a 85 kWh battery and 265 mile range, the discharge losses are already included.)

The vast majority of the reason an EV is cheaper to operate is because coal is so much cheaper than gasoline. Coal costs about $50 per ton. A ton of coal has approximately 24 GJ of energy. That's about 0.21 cents/MJ. Gasoline costs about $3/gallon, and has about 120 MJ/gallon, or 2.5 cents/MJ. For the same amount of energy, coal is an order of magnitude cheaper than gasoline, which gives the EV a huge advantage in terms of operating costs. This is not a bad thing - being able to transfer a cheaper but traditionally static energy source into use in a mobile application is an economic win. But don't confuse it for better efficiency.

Yes you could argue that we can make electricity from renewables. But the vast majority of the cost of renewables is in the initial production of the turbine or PV panels. Operating costs are nearly nil (limited to maintenance). So for a fair comparison you then need to incorporate production and transport costs. At which point renewables lose because on a per Joule delivered basis, even with coal plants being only 40% efficient, coal is still cheaper than wind and solar power. (Wind is only about twice the cost of coal, so cheaper than gasoline, but I suspect solar would be about the same cost as gasoline.) You need to incorporate cost of harm done by pollution for renewables to pull ahead. (And even then, only hydro, wind, and geothermal. PV solar still has a ways to go.)

Comment Re:This is stupid (Score 1) 280

Either compare flying a small plane to driving a car, or compare a huge bus to a plane.

No, you want to compare likely transportation alternatives. If you're going to go on vacation, a likely decision you'll face is whether to pay for airline tickets and fly, or pay for fuel (and possible rental) and drive. That makes the plane vs. car comparison completely valid. Same reason a car vs. bus comparison is valid for intra-city travel, even though you've defined them as being nothing like each other. In fact the bus vs. plane comparison is probably the least valid, since the vast majority of buses are used for intra-city mass transport, while the vast majority of planes are used for long-haul inter-city transport. So it's very rare (at least in a large country like the U.S.) for you to have to decide between taking the bus or taking the plane.

Incidentally, I'm not sure why this is news. These types of comparisons have been done before. Trains win. Then planes, then cars, then buses, then way at the bottom are taxis (which is why "services" like Uber are a bad idea - you want to minimize the number of taxis driving around).

Buses are rather interesting in that you'd think they'd score better than cars. But the fundamental problem you come across with mass transit buses is capacity vs convenience. You want to load each bus with as many people as possible to decrease its fuel consumption per passenger mile. But you also want to run the buses frequently so people aren't stuck waiting 45 minutes at a bus stop and instead decide to bum a ride from a friend or (worse yet) hail a cab. These conflicting demands mean you run the buses a lot more than would be ideal from an energy efficiency standpoint. Air travel avoids this problem by forcing people to adapt to the airline's schedule (other than a few shuttle services between well-traveled routes, and even those have mostly ceased service).

Comment No it doesn't more efficient (Score 1) 280

One factoid is interesting: it takes 4,211 BTUs per person mile to drive. This number will fall as we switch over to electric vehicles. For example, a Tesla Model S takes about 1,100 BTUs per vehicle mile.

No it doesn't. 1100 BTU (0.322 kWh) is the energy consumption from the battery to the wheels. You need to include the entire energy generation chain to get a fair comparison. Add in a 40% efficient coal plant generating the electricity, 97% transmission efficiency over high-power electrical lines, and 75% charging efficiency and the Tesla actually uses 1100 / (.4*.97*.75) = 3780 BTU per vehicle mile.

The vast majority of the reason an EV is cheaper to operate is because coal is so much cheaper than gasoline. Coal costs about $50 per ton. A ton of coal has approximately 24 GJ of energy. That's about 0.21 cents/MJ. Gasoline costs about $3/gallon, and has about 120 MJ/gallon, or 2.5 cents/MJ. For the same amount of energy, coal is an order of magnitude cheaper than gasoline, which gives the EV a huge advantage in terms of operating costs. This is not a bad thing - being able to transfer a cheaper but traditionally static energy source into use in a mobile application is an economic win. But don't confuse it for better efficiency.

Yes you could argue that we can make electricity from renewables. But the vast majority of the cost of renewables is in the initial production of the turbine or PV panels. Operating costs are nearly nil (limited to maintenance). So for a fair comparison you then need to incorporate production and transport costs. At which point renewables lose because on a per Joule delivered basis, even with coal plants being only 40% efficient, coal is still cheaper than wind and solar power. (Wind is only about twice the cost of coal, so cheaper than gasoline, but I suspect solar would be about the same cost as gasoline.)

Comment Re:The FAA Tried to Study This (Score 1) 36

Maybe they were afraid that small airports that do have controllers would start replacing those people with the remote setup. If those airports only get infrequent traffic, a couple of guys in a remote control tower can probaby handle dozens of them.

What surprises me is that the union actually has the clout to stop this.

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