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Comment: Re:At the same time (Score 1) 323

True but...

A the time Model 80 was their ONLY model that used the 386, it was top end and crazy expensive. I never actually saw one. IBM was still offering entry level models based on the 8086. The cloners had long since abandoned the 8086 and had a large offering of fairly reasonably-priced 16MHz 386 machines in their arsenal.

They also offered entry level PS2 machines with ISA slots, but for some reason they did not offer any machines with both ISA and MCA slots. This was probably a good technical decision, but it was a marketing disaster. Then there was the non-standard HDD, non-standard floppy drive, non-standard graphics, etc.

In 1987, people were still looking to IBM to set PC standards, but they did such a craptastic job at such an unreasonable price that they became completely irrelevant.

Comment: Re:The utilities have reason to be upset (Score 1) 514

by cnaumann (#49593881) Attached to: Tesla Announces Home Battery System

"Because the transformers which convert distributed power (typically lower frequency and higher voltage) to the household power (60 Hz / 240 VAC split-phase) are made to work efficiently, one-way. Going the other way, they are considerably less efficient."

No.

Everything on a power grid operates at exactly the same frequency. DC interconnects and other exotic technology aside, it is one gigantic synchronous machine. If load increases faster than supply the frequency of the entire gird slows down a tiny amount, as supply increase and load drops, the frequency goes up a tiny amount. Supply is continuously adjusted to keep the frequency stable. It is like a train. Locomotives tend to speed it up, wagons tend to slow it down, but it is all going at the same speed.

Power transformers are not "considerably less efficient" "going the other way" .

It can, however, be a matter of who is paying for the inefficiency of the conversion. Assume that a transformer at the distribution level is 90% efficient going either way. So the power company has to generate 1.1 units of power to get 1.0 unit of power through your meter. They take that into account when they figure out how much to change. However, if you sell power back to them at the same rate, that 1.0 units of power you generate is only 0.9 units of power back on the grid. So if you take a unit of power off the grid at one point during the day and give it back at another point during the day, you net bill is zero but the utility company has lost 0.2 units of energy during the conversion.

Comment: Re:With REALLY Huge Fans... (Score 1) 280

by cnaumann (#49587959) Attached to: New Study Suggests Flying Is Greener Than Driving

The biggest advantage that liquid hydrocarbons have over conventional batteries is that you can use air as the oxidizer. The oxidizer is much, much heavier than the fuel. Think about it. For burning hydrogen, the oxidizer is 8 time the mass of the hydrogen. For burning carbon, the oxidizer is over 2.5 times the mass of the carbon.

But you don't have to use conventional batteries to operate an electric vehicle. You could use hydrocarbon-air fuel cells.

Comment: Re:The grid needs storage - not battery storage (Score 1) 334

by cnaumann (#49569239) Attached to: Why Our Antiquated Power Grid Needs Battery Storage

There are a lot of household tasks that use electricity that can be rescheduled to reduce peak demand. Water heating is a prime example.Lots of folks take a shower in the morning and leave the house. The water heater turns on to make water that will not be used in great quantity for 8 or even 24 hours later. If the water heater were smarter, it could keep a little hot water available for washing hands and stuff, but recharge overnight.

Your freezer could work in a similar way. It could be set to get colder at night and a little warmer in the day to reduce peak demand.

Air conditioning systems could run dehumidification cycles at night to help reduce the burden during the day. They could also increase temperature slightly at the neck in the 'duck curve' (late in the day where solar generation is ramping down, but demand is still very high).

Clothes drying and dishwashing could be scheduled to run at night.

The simplest way to make all this happen is for the utility companies to start charging different rates depending on the incremental cost of the power being generated. The utility company would update your meter several times a day, the meter would communicate with your appliances and you would have to decide if it is all worth it.

Battery storage at the household level may be part of the solution, but it is difficult to justify for most markets at the current prices of electricity and batteries. If you were paying a dollar per kilowatt hour for peak rates, you might think a little differently.

Comment: Re:So Germany is not a state? (Score 2) 265

Getting a core non-critical is the _easy_ part. Change of core geometry, loss of moderator, pretty much anything will take the core non-critical. The cooling down part is what is tricky. You don't just have a big chuck of material at some temperature that simply need cooling, the core will continue to generate gigawatts of heat due to the decay of short-lived isotopes for several days/weeks after it has been rendered non-critical. Simply dumping nuclear lava on a concrete floor will not work. You have to spray it or flood it with borated water which will produced copious quantities of highly contaminated hot water, steam, and hydrogen. You can't keep all that material in your containment building...

The disaster at Fukushima Daiichi clearly demonstrated that containment buildings are all but worthless.

Comment: Last fully supported version of Windows (Score 2) 640

by cnaumann (#48803733) Attached to: Microsoft Ends Mainstream Support For Windows 7

I have noticed a trend. There are several engineering software packages that I use that simply will not run under Windows 8. The vendors have basically said use Windows 7 (or even XP) or move to Linux. This obviously does not affect most users, but it is interesting.

I have used the UI for Windows 8 for a couple of years now. It works, but I do not like it. I think it is rather poorly designed.

So other than the fact that it will not run the programs I need and I do not like the UI, I guess it is a pretty good operating system.

Comment: Re:But does it report artificially low ink levels? (Score 1) 270

by cnaumann (#48576597) Attached to: Keurig 2.0 Genuine K-Cup Spoofing Vulnerability

Have you complained to Keurig directly about the "genuine K-Cups" that will not function and asked for replacements? The only way to prevent this sort of crap is to raise a stink about it. Also consider returning the coffee maker and gving it a negative review on Amazon. Seriously, why are you putting up with this quietly?

Once it hits the fan, the only rational choice is to sweep it up, package it, and sell it as fertilizer.

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