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Comment Re:Wake me up... (Score 1) 108

Remember: I-squared-R losses go up with the SQUARE of the current. So running 1.2V across a board to your chips loses 400 TIMES as much power as running 48V to the regulator next to them.

Oops. Make that "loses 1600 times as much power". (Multiplied the 10s but forgot to multiply the 4s.)

When a board has several chips running at 10 or more watts apiece you can easily be dealing at currents where the heating of the board consumes more power than the heating of the chips. With a rack of electronics dissipating several KW you can pay for a LOT of tiny switching regulators to avoid more than doubling that.

Comment Re:Wake me up... (Score 1) 108

Give me a call when those fuel cells are ready for deployment, then we can talk about all these wonderful uses. No talk about the carbon footprint of operating fuel cells?

Natural gas (methane) has the highest energy/carbon emission ration of any saturated hydrocarbon (gas or oil) and beats the HELL out of coal. If you're going to use fossil fuels (or renewable fuel from biodegrading vegetable waste, sewage, or cow flops), and a fuel cell is in the efficiency ballpark with a grid plant, why not put the fuel cell in the rack?

The article mixes the use of fuel cells as a power source with efficiency improvements. The only place that makes sense is with the minor savings that may be seen by eliminating DC converters, but you will still need DC regulators which will have some losses.

Fuel cells are not limited by the carnot cycle efficiency limt. They can be FAR MORE EFFICIENT than a heat-engine based power plant.

Modern circuit boards in servers ALREADY HAVE switching regulators near the chips. With the very low operating voltages of modern electronics, the supply currents are SO high that you lose less energy by running 48V on the power planes of the PC board and regulating it down at the load than you do running, say 3.3, 2.5, or 1.8 volts and a correspondingly higher current across several inches of thin copper.

Remember: I-squared-R losses go up with the SQUARE of the current. So running 1.2V across a board to your chips loses 400 TIMES as much power as running 48V to the regulator next to them. It's like high-tension transmission lines in miniature. (They'd go higher except that over 50V gets you out of the easy part of the electrical code and into the region where electrocution becomes a major issue.)

Putting the switching regulator next to the chip also gives you much more stable voltage. When it's already there to save power, this makes good regulation "cheaper than free".

A major oversight of this article is the fact that fuel cells are major heat generators, not something you want in a data center. They would need to be installed in a separated structure, therefore idea that "Rack-level fuel cells would do away with data-centre-wide electricity distribution for servers" is hard to imagine.

They also need and external air supply and to have their exhaust removed rather than dumped into the room air. So you're going to give them their own plumbing. You want to SAVE that heat to keep the oxygen-transport style cells at operating temperature without wasting fuel or power to do it. So you insulate the box and run the ventilation plumbing like a stove pipe - coaxial, with the hot exhaust in the middle and the cool incoming air on the outside. This minimizes the heat loss to the room and acts like a counter-current heat exchanger to preheat the fresh air with the heat from the exhaust, while cooling the exhaust.

It's similar to what I did with my first unix box, back in the '80s or so: The thing put out as much heat as a space heater. So I hooked up a dryer vent hose to the 4" exhaust fan and dumped the hot air outside. Cooling problem solved. (In the winter I dumped it INSIDE to save on heating bills.)

Comment Your heater and furnace need electirc? Mine don't (Score 1) 108

Right now, if I don't have electric and gas, my water heater and furnace become inoperable.

In my remote house my heat and water heater both work fine on only propane. As long as the tank is not empty we're fine (and the tank only needs filling about three times a year).

The water heater is gas with a pilot light and no electric controls (except for the pilot light safety thermocouple, which generates enough power from the flame's heat to control the safety shutdown).

While the regular furnace has electronic controls and blower, I also have a backup: A propane "fireplace" stove in the great room, with a room layout that lets it heat the living area and keep the pipes from freezing.

Again it works with a pilot light, and the thermocouple's few millivolts also provide enough power, controlled by a mechanical-switch thermostat in the middle of the house, to operate the main gas valve as well. Though the stove's room blower will also fail in an outage, convection is more than adequate to circulate the heat in the big-open-space-in-the-middle house design. Kept things nice and comfy when we had a day-long outage in deep winter.

When away the stats are set to 55 for the furnace, 50 for the backup stove. This worked just fine one winter, when the furnace's draft sensor failed and the furnace was dead for weeks until we got there and discovered the issue. That definitely paid for the stove in one event.

Comment CO2 (Score 1) 108

If you have a fuel cell that burns methane (i.e. Natural gas) or other fuels the fuel cell will have to reform it into Hydrogen (releasing CO2) before it's used.

And if you're ultimately running from fossil fuels, methane is the least carbon-emitting choice.

Burning the hydrogen atoms to water produces MOST of the power from fossil fuels. Burning the carbon to CO2 produces a little more. But in gas and oil it's mostly there to make the hydrogen easier to handle than H2.

Methane has four hydrogens per carbon (4:1), the best ratio of all hydrocarbons. Ethane: (6: 2 = 3:1), propane: 8:3 = 2.666..."1, and so on. As you transition from gasses to oil you're approaching the large saturated hydrocarbon molecule limit of 2:1.

Then there's coal, where you're JUST burning the carbon. All CO2, much less energy (though still plenty if you burn ENOUGH of it).

Tell me when they come up with a range of affordable, small, light weight, fuel cells that efficiently make a couple hundred to a couple thousand watts by burning odorized propane with ambient air. I want one for my car, one for my travel trailer, and one for each house.

Comment Re:What's a fuel cell? (Score 1) 108

Electrolysis is not cost effective and requires more electrical power than your fuel cell could produce.

By the same argument, power grids "are not cost effective" because they require more electrical power input than they deliver to the cu
stomer.

Electrolysis may be VERY cost effective. Just think of it as a different sort of energy distribution system, not as a conversion of fuel to electricity, and compare its costs to what it replaces.

(This is similar to the bogus argument against solar panels: "They take more energy to make than they deliver over their lifetime." First that's false - they reach energy breakeven very early in their life. Second, they produce post-carnot-cycle electricity, while most of the energy going into making them is pre-carnot-cycle heat. Third, you need to compare their energy consumption apples-to-apples: How much energy does it take to build and fuel the fraction of the power grid that would deliver the same amount of electricity to the same site - from melting steel to build transformers, to clearing trees and stringing poles, to building power plants and switchgear, to fueling the plants to make the electricity (digging for and transporting coal, drilling for and pumping oil, disposing of radioactive waste, ...) to losing a fraction of that to carnot cycle efficiency, transformer losses, corona discharge, resistive heating of transmission lines, ...)

Comment Re:It's time to kill off the boomers. (Score 1) 400

Those so-called "Death Panels" already exist. Why is it alright for Insurance Companies to pick and choose who gets to live, and who must die, while bankrupting even more people in the process? I'd feel much safer if "profit" wasnt a primary variable in whether me or my loved ones get to live or die.

A rhetorical question deserves a rhetorical answer:

Because, with private insurance companies, you can either change policies or insurance companies, to get policy terms (and "death panels") more to your liking. Or you can dump the insurance company altogether and pay the hospitals as many buck as they ask to get as much health care as you both need and can afford.

With Obama care:
  - You're forced to buy insurance.
  - You're forced to buy a plan the government approved.
  - You're forced to buy a plan with some very expensive coverage that you may not need or want.
  - And the government picks your "death panel". Don't like that one? Find another country.

Comment Re:Now Open It (Score 1) 231

SAP upgrades can easily take that long, but SAP can easily run organizations an order of magnitude bigger, and two orders of magnitude more complicated than Tesla.

From the comments I'm readin in this story, my take home messege here is that SAP probably shouldn't run organizations at all. What the hell does their software do for all this expense and hassle anyway?

Comment Mod parent up. (Score 2) 231

In my experience, the biggest problem is when the CIO is not allowed to refuse requests. Once that is cleared (and the CIO is competent) then projects get finished on time and on budget.

In this case, it sounds like Elon had a lot of confidence in Jay's ability as CIO.

Submission + - Captain James Kirk is now commanding a destroyer 1

mcgrew writes: The Wall Street Journal is reporting that Captain Kirk will be commanding the U.S. Navy’s most advanced destroyer.

On screen, the newest Capt. Kirk is a brash, headstrong, rebellious commander who gets in bar brawls, defies orders from his superiors, and temporarily loses command of the Enterprise. The real life Capt. Kirk is expected to have a much more sedate command. “No stories of him kissing green aliens or yelling ‘KAAHHHNNN!’ on the bridge of his ship,” said Mr. Servello. “No worry over him stealing his own ship to chase after Spock, although I am told he is looking for a chief engineer named Scotty.”

Comment Re:clemency? (Score 5, Insightful) 504

Basically her response is that of the bankrobber who is angry and blaiming his friends for turning him in rather than himself for being caught with the cash.

The response of the entire administration has been the response of a spoiled, petulant teenager.

In fact, this has been the response of the administration -- and the previous one -- to just about any development or obstancle they don't like.

The US is no longer a nation of laws. It is a nation of men (and some women) who are impulsive, incompetent, largely juvenile, disrespectful of their offices, and contemptuous of both the public and the law. The Administration is being run by people with the mentality and motives of a cast of Saturday morning cartoon, or late Thursday night TV villains. Unfortunately these people have one common talent -- they are all connected to each other like threads in a rotten carpet.

Not a nation of laws. A nation of men. And a particularly base and uninspiring kind of man at that. Central and South American countries have been run by such men for centuries. Run into the ground. The US, for all its power and potential, is now being run into the ground as well.

The end result is probably something like Singapore. Ostensibly free, but scratch the surface and you quickly hit authoritarianism and an oligarchy of connected families and companies. The problem is, most of the US governing class would see little wrong with such an outcome.

Comment Re:Yes it is (Score 5, Insightful) 398

Pretty much all foreign intelligence agencies already knew about what the NSA was up to; the USA government IS upset because Snowden informed the USA general public.

What the NSA was and is doing wasn't a big secret among governments. Many of the governments now complaining about being spied on cooperated with the USA to gather and share much of this information. Yes, they might be pissed that the USA crossed a few lines here and there, but they knew the USA was spying on everyone.

Comment And now they get ripped off, too. (Score 1) 195

Top performers burn out fast and do not return to the IT field.

And now they get ripped off, too.

People with links to other talented, employable, people have been getting finder's bonuses from their employers for recommending a good candidate.

Now Google has patented mining their email and social network metadata so THEY can get a hiring fee. They just monitized the money out of their subscribers' pockets into their own.

Comment Re:Unimaginable wasting of money (Score 1) 219

The price of living in a free society is that occasionally someone is going to get pissed off at the world and blow up spectators at a marathon or take a gun to a classroom of kiddies. It would be great if we could stop this, but if the only way of stopping it is to take away your freedom and allow the government to spy on its people then maybe the price is too high.

Assuming that such things would actually be effective in the first place. Even if they were that they wouldn't put the public at greater risk from rogue "law enforcement".

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