Of course they loved it. They got all the goodies the locals can only dream of and, more important, the tourists are allowed to leave.
Oh, what do you call an institution where you get shot in the back if you try to leave?
John
Bush
Sell it and buy a ski lodge?
John
I don't know about those you mention but the published peak efficiency of the ones in the Prius (including the inverter) are about 93%, put two in series and the losses to convert from mechanical energy back to mechanical energy when operating at peak efficiency would be about 15%
- for other operating conditions they can be a lot worse, hence my 20% number.
AC Propulsion
When considering regenerative efficiency the numbers get even worse - the battery may only have a 70% efficiency giving only a 50% overall energy recovery efficiency.
Undoubtedly the efficiency could be improved but would add weight and cost - Toyota and Honda are the only manufacturers with real-world experience of producing this class of machines in million unit quantities so presumably these designs represent their view of the optimum compromise for this application
kevin
A point. Those technically able to to do such an investment regard living the 18 years as doubtfull. Those with a good prospect of seeing these 18 years regard the investment beyond their reach. Apparently none these days is willing to do an investment for the future generation.
A pity.
Rene
Most of the stuff sold for residential use is so incredibly crude. I mean, what would it take to design an automatic mixer between hot and cold? It ain't rocket science and has been done before.
[...]-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
power.
But from what? Usually water rights and all that have been divvied up "appropriately" many moons ago.
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Deregulation can be good if there is competition. Airline travel was pretty much restricted to upper class folks before deregulation. But deregulation while keeping monopolies in place is IMHO not a good thing.
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many
Dense central urban populations take the train or subway. Suburbanites have no choice, so most of this conversation is geared toward them. And guess what, a whole lot of the U.S. is suburban. . . .
Tim
-- Deep Fryer: A very philosophical monk. Website @
There is no design needed. You can buy just such a valve already.
There's a used one.
On May 18, 3:00 pm, "Tim Williams" wrote: [....]
AC motors are not all that hard to generate power with, if you already have AC power systems to run them. If the slip frequency goes negative, the terminal impedance of an AC motor has a negative real component.
They are permanent magnet AC synchronous 3-phase motors - so they don't need excitation.
They use a DC rail of up to 500V (650V in other Toyota models) feeding three half bridges to drive the motor pretty much as you describe.
They are not set into reverse to regenerate though, the PWM duty-cycle is controlled to give boost so that current flows into the battery rather than out. They can regenerate with a road-speed as low as
7mph, while allowing over 100mph before they run out of control because the BEMF exceeds the rail voltage.kevin
I know those, they also come within single-lever shower/bathtub control valves where you just set a temperture instead of a percentage. I think Grohe makes them. But most aren't fast and when you have the situation that Jeff saw in Israel the water coming through the pipes can turn from barely warm to scalding in milliseconds. Unless you have a point-of-use recirc but most houses are not that modern.
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Can't see the spreadsheet but IIRC it does cost that much. As people who moved into this area have painfully found out. Real estate is less expensive than the Bay Area but the rude awakening comes when the A/C is used. Then PG&E begins to charge them through the nose. Same for people with heat pumps in winter. Which is why we had a heat pump in Europe but do not have one here.
The reason why PV is popular in Europe is that goverments there provide HUGE subsidies. They often get well north of 50c/kWh and the other ratepayers foot the bill. There is no free lunch.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
One solution that I saw was an inverted siphon between the mixer output pipe coming out of the wall, and the shower head. The pipe was about 6 ft long. There was a bi-metallic thermometer clamped to the entry point. My guess is that it would give about a 3 second warning of impending thermal excess. The installation looked commercially done and may have been part of aftermarket kit. As I was a visitor, I didn't give the shower a proper test flight.
It would be fairly trivial to build a proper mixer, with electronic (or bi-metallic mechanical) temperature control and independent flow control. There were some on sale in Israel in the early 1970's when I was there. It's just that the apartment where I was living didn't have one and apparently nobody thought the cost was justified. People can get used to almost anything.
I once had my bathroom sink setup as in a medical office or surgeons wash room. Limited manually adjustable temperature (to insure self sterilization) and foot switch operated flow control (to prevent contaminating the hands). It saved considerable water and by implication, considerable energy heating the water. My ladyfriend at the time found it "inconvenient" so I reluctantly removed it.
An IR faucet adapter:
The same device could easily be installed in a shower, with foot valve operation. Set the temperature with a controlled mixing arrangement and adjust the flow (or more crudely on/off) with a foot switch. It's even patented:
So, what's preventing such installations in the home? I once discussed the issue with a local doctor, who was building a new house at the time. The Uniform Building Code for residential dwellings won't allow such innovative plumbing. It's perfectly acceptable for commercial and hospital, just not residential. I'll supply a suitable conspiracy theory when I have time.
Hmmm.... I still have the parts of the foot operated sink valve somewhere. I should try to resurrect it.
Incidentally, one of the old but fun problems with hospital water control is selecting the temperature. One set of regulations demanded that the water be hotter than 52C in order to minimally self sterilize. Another set of regulations from a different agency, demanded that water be no warmer than 52C to prevent scalding. This was about 10 years ago, and hopefully a suitable compromise has been reached by now.
"Control of nosocomial Legionnaires' disease by keeping the circulating hot water temperature above 55 degrees C: experience from a 10-year surveillance programme in a district general hospital."
Google couldn't find anyone using a rooftop solar water heater as a drinking water purifier or pasteurizer. Stand alone yes, but not part of the water heater pretzel:
Yet another opportunity ignored.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
My wife works in a hospital where one inspection agency requires plastic-bag liners in trash cans, and another agency forbids them. They adjust according to which inspection is scheduled.
John
Y'er news header shows that you're using Windoze. You might want to download the various Word, Excel, and Powerpoint viewers from Microsloth.
Word 2003:
Excel 2003:
PowerPointless 2007:
Visio 2003:
"The world's largest solar power plant is only the latest addition to Germany's investment in alternative power..."
The way I understand it (from a rather marginal TV documentary) the logic is that when the oil runs out, Germany will have electricity while most other countries will not. It's also part of creating jobs and dealing with the unemployment problem. German taxpayers apparently paid about $3.8 billion last year to subsidize alternative engergy sources. Whatever it takes.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
A friend had the same sort of problem with trash can lids in his restaurant. The county health inspectors insisted on them and the state inspectors gave him a major ding for having them.
-- Keith
One more for your collection. OSHA requires rubber mats in the food preparation areas in order to prevent slip and fall due to slop on the floor. Some other hospital safety agency forbids such rubber mats to facilitate slop cleanup and prevent filth accumulation in the mats. The hospital currently uses the same strategy. Rubber mats are either deployed or well hidden depending on the scheduled inspection type.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Wait a year; that's Obama's energy plan too.
-- Keith
^ ^ ^ ^ ^ ^ ^ ^
Ok, then that's included in my list (maybe not explicitly). Permanent magnet you just strap on a rectifier and boost converter, but you have the weight of the magnets to contend with, which I've got to imagine is quite substantial in the many-HP range. Or are these magnetized cage rotors, so, er, semi-synchronous I suppose might be a way to put it. (Full magnetized rotor is synchronous, nonmagnetized "squirrel cage" rotor (which I was thinking of with "AC (induction) motor") is the regular deal.)
Alright, which is like what I went on to say, but AC?
God, that must be awful, you need to run a VFD in reverse. So to suck power from it, you need to synchronize the rate with the shaft? Minus the difference which is power drawn of course.
I suppose it's no BFD if you have a bidirectional (power in/out) self contained VFD controller inside a feedback loop that's controlled by the gas/brake pedals to make it feed power out of or into the battery, but that's an awful lot of trouble. I'd just as soon go for a frickin DC motor, but maybe it's not as efficient.
Tim
-- Deep Fryer: A very philosophical monk. Website @
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