More accurately, it is not energy efficiency but energy storage volumetric efficiency, or the ability to store large amounts of energy densely that is important in a vehicle. An electric motor is much more efficient than an internal combustion engine, but that is more than offset by the poor energy density (and mass) of batteries compared to gasoline or other chemical fuels.
---------- >From: "Scott Lacey" <sco...@world.std.com> >To: "Ted Rook" <t...@crestaudio.com> >Cc: emc-p...@majordomo.ieee.org >Subject: Re: 1kW per square meter.......free >Date: Sat, Jun 8, 2002, 12:15 PM > > > Ted, > > While most "alternative energy" schemes sound very promising, energy efficiency > problems make most of them impractical for real world use. Small solar charging > systems are great for maintaining a charge on a seldom used battery in a spare > automobile, or similar application, but the ratio of charge time to usage > has to be > large. The problems with a solar powered automobile would be: > > 1) Lots of expensive (and unsightly) solar panels plus the numerous serial and > parallel connections needed to make a usable system. Even then, the car would > have to be parked in the sunlight many more hours than it was driven. > > 2) An expensive buck/boost charge controller to compensate for the enormous > voltage variations due to weather. > > 3) A trunk full of heavy, expensive batteries, with their need to be eventually > replaced. > > 4) And finally, how would the batteries be charged if it rained for four or > five days > straight? > > The hybrid gas/electric vehicles seem to be the only practical electric > vehicles made > so far. And even these seem to be expensive enough that sales have to be > subsidized. > > I know people who have tried to use solar dc electrical systems at remote camps. > You have to strictly ration electrical usage even if you only use the place on > weekends after it has charged all week. Most people eventually revert to using > combinations of propane, gasoline, and kerosene for light and cooking. A gallon of > Coleman fuel will last a week running a stove and some lights. > > As to the energy efficiency of gasoline, years ago I watched a > demonstration where a > homemade mortar lobbed a sand-filled beer can hundreds of yards using a > SPOONFUL of gasoline! It graphically proved the point about why it is so hard to > replace the internal combution engine. > > Scott Lacey > On 7 Jun 2002 at 13:52, Ted Rook wrote: > >> >> sorry, off topic, mostly for US residents: >> >> just imagine everyone's car being coated with 'solar cell generator' >> material with a storage device in the trunk...... >> >> and how about air-conditioners that run on the Stirling cycle from a >> solar energy collector... >> >> lousy for the oil lobby but fantastic for the human race >> >> >> >> >> >> ------------------------------------------- >> This message is from the IEEE EMC Society Product Safety >> Technical Committee emc-pstc discussion list. >> >> Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ >> >> To cancel your subscription, send mail to: >> majord...@ieee.org >> with the single line: >> unsubscribe emc-pstc >> >> For help, send mail to the list administrators: >> Ron Pickard: emc-p...@hypercom.com >> Dave Heald: davehe...@attbi.com >> >> For policy questions, send mail to: >> Richard Nute: ri...@ieee.org >> Jim Bacher: j.bac...@ieee.org >> >> All emc-pstc postings are archived and searchable on the web at: >> http://ieeepstc.mindcruiser.com/ >> Click on "browse" and then "emc-pstc mailing list" > > > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" > ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
