The Drive-a-Toyota Act
in [Toyota]
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From: Bill Putney on 6 Jul 2007 18:34 Jeff wrote: > Bill Putney wrote: > >> Jeff wrote: >> >>> Cars can also have electrically powered water pumps, power steering >>> pumps, valves, and compressors for the air conditioners, although I >>> don't know if any do, yet. >> >> >> An honest question: All those things suck energy whether mechanically >> or electricaly powered (and the power has to ultimately come from the >> IC engine). For each one, is the electrical version inherently more >> efficient than a mechanically powered (belt or gear driven) one? > > > I think the electrically powered ones of these are usually more > efficient, because they can be more efficiently shot off (even if you > shut off the A/C, there still is loss from friction in the pulleys) and > they operate at the proper speed (the A/C compressor in my car would run > a lot fast if I drive in 3rd gear on the highway instead of 5th). OK - makes sense. > Plus, I think the generating mechanism on a hybrid means less wasted > energy. Assuming you're not meaning strictly the regenerative braking, can you explain what you mean? You're saying that the mechanism it uses to convert mechanical energy into electrical energy is more efficient than the alternator (the auto mfgrs. are back to calling them generators now) in a traditional car? How is it done? Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
From: Bill Putney on 6 Jul 2007 18:53 Is your last name O'Shaughnessy, by chance? At VA Tech, there is a dormitory named O'Shaughnessy - everyone has always called it O'Shagnasty. Oh those crazy college kids! Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
From: Jeff on 6 Jul 2007 18:58 Bill Putney wrote: > Jeff wrote: > >> Bill Putney wrote: >> >>> Jeff wrote: >>> >>>> Cars can also have electrically powered water pumps, power steering >>>> pumps, valves, and compressors for the air conditioners, although I >>>> don't know if any do, yet. >>> >>> >>> An honest question: All those things suck energy whether mechanically >>> or electricaly powered (and the power has to ultimately come from the >>> IC engine). For each one, is the electrical version inherently more >>> efficient than a mechanically powered (belt or gear driven) one? >> >> >> I think the electrically powered ones of these are usually more >> efficient, because they can be more efficiently shot off (even if you >> shut off the A/C, there still is loss from friction in the pulleys) >> and they operate at the proper speed (the A/C compressor in my car >> would run a lot fast if I drive in 3rd gear on the highway instead of >> 5th). > > OK - makes sense. > >> Plus, I think the generating mechanism on a hybrid means less wasted >> energy. > > Assuming you're not meaning strictly the regenerative braking, can you > explain what you mean? You're saying that the mechanism it uses to > convert mechanical energy into electrical energy is more efficient than > the alternator (the auto mfgrs. are back to calling them generators now) > in a traditional car? How is it done? A generator converts mechanical energy to DC current, not A/C current. Because Toyota is so concerned with efficiency with the Prius, having an efficient generator system must have been a priority. And the output doesn't have to be converted to D/C with a rectifier. There's power loss in the rectifier. (All automotive alternators have them.) Plus, the drive to the generators is direct drive, not belt drive driven, so there is less friction loss with a generator than a belt-drive. It is also inherently more efficient to drive these things from electricity than directly from belts, because they run at the proper speed, not a speed determined by the engine. Plus, you don't need to run the engine to run the A/C or other things, which saves on fuel (although you need to run the engine every now and then to recharge the batteries or otherwise recharge the batteries) and you can use regenerative braking to recharge the batteries. SO there are a whole bunch of reasons why it is better to run these things off of electricity, not just one. Jeff > Bill Putney > (To reply by e-mail, replace the last letter of the alphabet in my > address with the letter 'x')
From: Bonehenge (B A R R Y) on 6 Jul 2007 19:22 On Fri, 06 Jul 2007 19:06:21 -0400, "Elmo P. Shagnasty" <elmop(a)nastydesigns.com> wrote: > >With those electric motors there to help with low end grunt and getting >the car moving, the engine can be tuned more specifically for running at >certain efficient speeds. I always thought electric motors would make AWD very simple.
From: C. E. White on 6 Jul 2007 19:34
"DH" <dh(a)stargate.com> wrote in message news:468e4ff9$0$20568$88260bb3(a)free.teranews.com... > "C. E. White" <cewhite3(a)removemindspring.com> wrote in message > news:468e5971$1(a)kcnews01... >> "DH" <dh(a)stargate.com> wrote in message >> news:468e45aa$0$32552$88260bb3(a)free.teranews.com... >> >>> I'll have to ask one of the Prius owners around here (Frostbite Falls, >>> Minnesota) if the car was comfortable in the winter. >> >> I saw one reference where they commented on the excellence of the heater. >> I don't think you need to worry. > > Simply using a heating element to speed up getting hot air from the > defroster is a good idea and, since I usually dress warmly in the winter, > anyway, probably meets my real need, which is to see the road. Even on a > conventional car, this would be a welcome feature. I wonder if any luxury > cars have it? > > Reminds me of a feature that Chrysler once offered on their minivans, a > windshield heating element located where the windshield wipers park to > help keep the bottom of the windshield de-iced and wipers free (I can't > believe no one has copied this feature, nor that Chrysler seems to have > abandoned it). For several years Ford (and GM on some cars) offered an electrically heated windshield. The windshields had a very thin nickel coating on the glass and when a high frequency AC current was applied, it would heat the surface of the windshield. I had this feature on a 1986 Mercury Sable. It was fabulous. When you got in the car, you pushed the windshield defrost button, and after about 20 seconds, the frost on the windshield just turned to water. Unfortunately it was a pricey option ($1k). Ford (and GM ) eventually discontinued offering it. You can tell a car that has the feature because at certain sun angles, the windshield will have a bronze tint. Ed |