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Comment Re:Why does the ESA have a worse record of landing (Score 2) 81

NASA picked up a lot of experience putting landers on the moon. The Soviets also sent a lot of moon landers, but never really ironed out the bugs (had a lot of failures). Those problems followed them to Mars where they went 0 for 6 (well, 1 for 6 but the single success ceased communicating after 14.5 seconds with no useful data received).

Comment Re:Oh Boy (Score 1) 130

Current Li-ion batteries only have about twice the energy density of NiCds. The reputation NiCds got for having lousy energy capacity was due to a memory effect. If you kept recharging the battery before it had been fully discharged, it "learned" the low charge state as its new zero state, and you lost that bottom portion of its capacity (due to crystalline growth).

Rechargeable batteries have increased about 2x in energy density in the last half century, and about 3.5x in the last century (from lead-acid to li-ion). So claims of a 10x increase in the near future are going to be met with a lot of skepticism.

Comment Re:AT LAST! (Score 2) 60

Oh wow! You POSTED A "VLAD IS FAT" REFERENCE! Congratulations!

Just kidding.

Posting Vlad memes is literally the most basic, desperate, tragic, hopelessly-void-of-meaning, outrageously obnoxious, troublesome, costly, and downright pointless cry for help that the universe has ever screamed. Wow, you were born as a merely BORDERLINE retarded member of your species. WOW! INCREDIBLE! You managed to open your web browser and go to Slashdot (which in evolutionary terms, willing translates roughly to "fucking desperate for at least a few reasons") managed to somehow visit Trolltalk and post a "LOCKWOOD IS FAT" reference that was stale in 2001! WOW! This has literally only been taking place for ALMOST TWENTY FUCKING YEARS! WOW! Except guess what, nobody even reads Trolltalk anymore... which means you failed at submitting yourself to an act which means absolutely nothing. The only thing left to do now is kill yourself.

Not nearly as obnoxious as your post.

Comment Re:How is Inform as a writing tool? (Score 1) 21

IIRC I once ran into a Steampunk in Second Life who did a bit of writing (participating in NaNoWriMo and such), who used Scrivener, but had dabbled a bit in IF using Inform.

I wonder if it would be possible to combine the two, using Inform to maintain a "database of attributes" for characters, locations, etc etc. Something akin to:

Aragorn is a Dunedain, Dunedain are also Numenoreans, Aragorn is the Son of Arathorn, who is also a Dunedain. Aragorn is a Descendant of Elros, Elros is the brother of Elrond. Elros has another name, Tar-Minyatur. Elros was the First King of the Numenoreans. etc etc.

Comment No, they handle 1.2% of all retail sales (Score 1) 62

TFA says they handle 15% of all online retail sales, maybe 20%-30% if you include third party sales handled through Amazon. Online sales comprise only 8.1% of all retail sales. So Amazon's (very small) slice of the whole pie is just 1.2%, possibly 1.6%-2.4% if you include their third party affiliates.

Amazon barely cracked the top-10 stores in retail sales for 2015. There's a tendency for people who like to be online to over-exaggerate the effect of the Internet. Retail sales are still very much a brick and mortar business.

Comment Re:For all the night shift Tesla owners (Score 3, Informative) 80

Localization of the power source doesn't matter. Everything is interconnected by the grid anyway, so only total generation and total consumption matter. Say everything except your Tesla uses x kWh.
  • Original case: x kWh generated, x kWh consumed.

Now add the Tesla and solar panels on your house:

  • Work night shift, Solar panels generate y kWh, Tesla consumes y kWh to charge (set them both to y to simplifiy):
    x + y kWh generated, x + y kWh consumed
  • Work day shift, Solar panels generate y kWh which is sent to the grid, Telsa consumes y kWh from the grid to charge:
    x + y kWh generated, x + y kWh consumed. Same as above.

Basically, if you work the day shift, the addition of your solar panels at your house reduces the amount of power the coal plant needs to generate by y kWh. When you plug the Tesla into a charger at work, it increases the amount of power the coal plant needs to generate by y kWh. And the whole thing is a wash. Exactly the same as if you charged the Tesla at home using (only) power from your home solar panels.

A lot of people don't seem to get this. The marginal increase power use doesn't have to be directly connected to the marginal increase in power generation to have the same effect. This is also why you should conserve electricity even if you're in the Pacific Northwest which is powered mostly by hydroelectric. Any reduction in your consumption means a little bit of hydro power is left over and can be transmitted to the rest of the country, and a coal plant elsewhere needs to burn a little less coal. Exactly the same as if someone living next to the coal plant conserved electricity.

For the same reason, EVs are predominantly powered by electricity from coal and natural gas, not by renewables. Those are the two power generation sources which are flexible enough to ramp up with increases in demand. EVs are only powered by electricity from renewables if you wouldn't have built the renewable plant if you hadn't bought the EV. If you would've built the renewable plant anyway, then it results in a marginal decrease in the generation from coal and gas, while the addition of an EV results in a marginal increase in the generation from coal and gas. So the EV's power is coming from coal and gas. This is the case even if the electricity from your solar panels are going straight to your EV. If in the absence of your EV the electricity from your solar panels would've instead gone onto the grid, then by putting it into your EV you are depriving the grid of those kWh, and a coal/gas plant elsewhere needs to generate those kWh.

Tesla understands this, which is why they're trying to link home solar installation with EV car purchases. If you can link the two, then the purchase of the EV results in the installation of PV solar generation which would not have existed without the EV. And then you can truthfully say the EV is being powered by electricity from solar.

Comment Re:Thankfully NASA took the pictures (Score 1) 108

NASA was much the same before the Challenger accident. The PR people had way too much power - enough to force a launch to proceed when the engineers were saying it wasn't safe.

I'm willing to cut the ESA a little slack here. Nobody was really hurt by trying to de-emphasize the lander's failure, and the bulk of the instruments are in the orbiter (which will also serve as a communications relay station for future missions). So while the mass media obviously was focused on the lander's failure, from a scientific standpoint the orbiter's success was the bigger story.

Comment Re:Weird... (Score 1) 66

That's a key difference between how regular people and rich people tend to think about money. $x million is an amount. Income is a rate. Regular people think having a large amount of money is being rich. $100 million > $50 million, so they'll take the $100 million. Rich people think having a high income is being rich. $100 million earning 5%/yr is increasing at $5 million/yr. $50 million earning 40%/yr is increasing at $20 million/yr, and will exceed the value of the $100 million in 5 years,. So they'll likely consider the $50 million to be the better choice. You can see this among lottery jackpot winners. The long-term payment (over 20-30 years) is usually the better choice, but most winners opt for the immediate lump-sum payment.

Likewise, Microsoft offered to buy FB for $24 billion because they thought that was the best place to invest their money to get the highest return on investment. Zuckerberg turned down the offer because he thought his highest ROI was in continuing to work on improving FB, rather than taking the money and investing it elsewhere. 50% of new companies fail within 5 years; 2/3rds fail within 10 years. So if you think the company you currently own is likely to experience strong growth, selling it with the intent of using the money to start a new company is a very risky proposition.

Comment Re:Walmart also uses direct solar (Score 1) 57

This. Commercial PV panels are about 18% efficient at converting solar energy into electricity, and the best fluorescent bulbs are about 15% efficient at converting electricity into light (the rest becomes heat). So if you install PV panels to power your lights, you're only converting about 2.7% of the sunlight hitting your solar panels into interior light.

In other words, covering your roof entirely with PV panels gets you as much solar lighting as cutting holes in 2.7% of your roof. The little squares in the Walmart pic you've linked covers about 1/12th the roof (one per 3x4 grid), or 8.3%. So it's providing 3x more free lighting than if you'd covered the entire roof with PV panels. Most of the warehouse stores I've been to (Costco, Home Depot, etc) use similar natural lighting extensively. (Note that you can still cover the space in between these skylights with PV panels.)

Comment Re:Economics? (Score 1) 337

0.9 is the historical capacity factor for nuclear in the U.S. Yeah, nuclear is really best for base load. It's slow to ramp up or down, so is not very good for peaking power load (the hourly and instantaneous spikes and dips in power consumption for the grid overall). Peaking load is usually handled by hydro and gas plants, sometimes coal.

The difference is that nuclear power proponents do not advocate making 100% of power generation nuclear. They are ok with using hydro, gas, wind, solar to handle peaking load. Renewable power proponents OTOH advocate 100% of our power come from hydro, wind, and solar, even though none of them are suitable for base load. Geothermal was really the only viable renewable for base load, but it has become collateral damage in environmentalists' war against fracking. (The energy of earthquakes triggered by fracking was already in the earth. If that energy hadn't been released by the fracking, it would've been released in a natural earthquake some time in the future. But in their zeal to shut down fracking for oil by incorrectly blaming fracking for all the energy released in an earthquake, they've poisoned public perception so that geothermal would also be blamed for earthquakes.)

As for rates for different power sources, wind is getting close to nuclear, but solar is still nowhere near. And as mentioned above, neither are suitable for base load. Most of the articles I've read proclaiming renewables will overtake nuclear and fossil fuels in cost mistakenly omit capacity factor in their comparison. They wind up comparing peak generating capacity, which has very little to do with rates. Theoretically you could use renewables for base load if you had sufficient storage capacity. But the most efficient storage system (pumped storage) only has about 75% efficiency, so that automatically makes it at least 1.33x more expensive than its source.

Comment Re:Economics? (Score 3, Insightful) 337

Nuclear power has a capacity factor of about 0.9. So a 1 GW plant will generate on average 900 MW throughout the year after taking into account downtime for maintenance and refueling.

8766 hours in a year (taking into account leap years), so that's 7889 GWh per year.

At a U.S. average rate of 12 cents/kWh = $120/MWh = $0.12 million/GWh, that's $947 million worth of power generated per year.

Nuclear plants are licensed to operate for 40 years. So that's $37.9 billion worth of power generated over 40 years.

Most of the older plants have had their license extended to 60 years. Some are requesting an extension to 80 years because everything is working just fine. So the actual power generated over the lifetime of the plant will likely be 1.5x to 2x higher.

So yeah, the $4.7 billion construction cost is tiny compared to the return you'll get. For your example of a 3.2 GW output plant that costs £24.5 billion ($30 billion) including financing, at the UK average rate of US$0.22/kWh, the expected power generated over 40 years would be worth $222 billion.

Comment Re:Clever design (Score 1) 259

online in pickup groups of strangers is for adults.

That's not what I said. I said you CAN play with random strangers but you can also FRIEND those strangers and play regularly with them if your play well together and your schedules coincide. You don't seem to understand the concept of "online friends". I've known certain people online for over a decade.

Perhaps being stuck in the past, you don't know about things like "friends lists" or "guilds" that exist in online games these days.

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