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Comment Re:Energy Conservation (Score 1) 710

Nuclear and solar are useful. However, you can't control them with the speed required to keep the net stable.
Natural gas ramps up in minutes.
Solar is unpredictable. You can't ramp it up.
Nuclear is slow. A controlled shutdown takes days.
If we want to fully switch to those resources we need large scale electricity storage. For example 20% of daily use in storage. The US used 4,095 x 10e9 kWh in 2012 according to wikipedia. That's on average 11.2 x 10e9 kwh a day. Assuming that my 20% figure is sufficient, that would mean that 2.24 x 10e9 kwh of storage is required.
If we use Li-Po batteries with 265 Wh/kg that is approximately 8.5 million tons of Li-Po batteries.
Ergo, currently such energy storage is unfeasible.

I agree with you on the coal. I don't know any reason why we should continue using that, apart from price. It is not as slow as nuclear but not fast enough to fix fluctuations in electricity usage. Not by a long shot.

Comment Re:LED Lightbulbs Re:user error (Score 1) 710

Do light bulbs use up *that much* of your electric bill? Huh. I thought that A/C or heating, plus refrigerator and other appliances took up 90% of your utility bill.

A/C: Incandescents produce heat, the AC has to work harder to remove that heat. Thus the energy savings should be multiplied by approximately 2,5 if the AC is running.

Heating: Heating electricity use can be lowered by using insulation and even moved from the electricity bill to the natual gas bill by using a gas heater. Not all places where people live need heating.

Refrigerator: Modern efficient refrigerators use far less power than lightbulbs use. Let's take a huge 215+89l refrigerator/freezer combo, class A+++: the Bosch KGE36MW40.
It uses approximately 149 kWh a year. If you have 10 bulbs of 50 watts running 3 hours a day that uses (10*50*3*365)/1000=547,5 kWh.

Comment Re:Security requires availability! (Score 1) 244

The old adage, being so tragically expressed here in real world terms, that the only "secure" computer is locked in a vault at the bottom of an ocean belies the very nature of security.

I always thought that was the response to someone requesting a completely secure computer. To explain why the requester really doesn't want what they are asking for.

Comment Re:user error (Score 1) 710

Modern dishwashers can be slightly more efficient than manual washing. But those A++ dishwashers are expensive.
Gas hot water over electric is not always an energy and cost saver. Usually the hot water is piped from the heater to the tap over a longer distance with gas heaters. The heat in the water in that piece of pipe is lost.
'round here the electric heaters are usually directly under the tap. 1 m of Ã10 mm (id) isn't much water. The gas heaters are often 10m away. With the same inside diameter that means there is 10 times as much lost heat.

Comment Re:So what? they can be tapped to. (Score 1) 244

If that is true, which is highly doubtfull, that 3g modem is only active when powered down. Powered down means there is no power to the memory banks. No power to the memory banks means the data in it will be destroyed in a couple of microseconds (bar cryogenic cooling). Ergo your encryption keys (which are in your memory banks) are destroyed.

And that is all dependent on that mysterious, magical "phantom power" actually working for a useful amount of time. On die capacitors are hellish expensive.

Comment Re:Automate successful execution as well (Score 1) 265

Disclaimer: I am not an IT professional.
Why not automate the deployment and go in via VPN afterwards to check if all is well?
Of course this should be done within driving range so that you can get there a couple of hours before business hours to fix the horrible, horrible mistakes that will be made from time to time. Or when the VPN doesn't respond.

Comment Re:Thrown from the vehicle (Score 1) 443

If I were a manager at Tesla I'd want to know how the car got stolen. Is the range on the keys too big? Does the car stop if it drives out of that range (which would mean the current driver has no access to the keys)? Were the electronics damaged before the crash? Was there a remote hack?

The crash, well, that is not as interesting. Most 100 mph crashes result in a mess. Not much you can do about that (unless you count limiting the max speed or adding so much support and crumple zones that it can't go 100 mph anyway)

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