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Post by jeffolie on Nov 23, 2010 11:07:28 GMT -6
lol Totally electric car 99 MPG according to EPA ====================================================== What’s Wrong With This Picture: The 99 MPG Non Sequitur Edition By Edward Niedermeyer on November 23, 2010 Why does the Nissan Leaf get a 99 MPG from the EPA? After all, you could pour gallons of gasoline into the thing and it wouldn’t budge an inch. It is, after all, an electric car. But hey, this ain’t America if a consumer can’t glance at a label and say “gosh honey, check out how many em-pee-gees this one gets. That sure is a whole lot of em-pee-gees.” And at least the EPA did include the most important detail: the Leaf’s battery range is rated 73 miles, or about three quarters the range Nissan had been claiming. Of course, as is always the case, your mileage may vary… only the amount of gasoline required by a Nissan Leaf won’t. www.thetruthaboutcars.com/2010/11/whats-wrong-with-this-picture-the-99-mpg-non-sequitor-edition/
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Post by graybeard on Nov 24, 2010 0:06:57 GMT -6
CNG, Compressed Natural Gas, MPG is measured in GGE, Gasoline Gallon Equivalent. I've never seen GGE for battery cars, but it could be calculated, based on KWH and GGE of CNG to provide the electricity.
The 99 mpg is probably a code for "No way to measure."
GB
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Post by unlawflcombatnt on Nov 24, 2010 1:34:02 GMT -6
CNG, Compressed Natural Gas, MPG is measured in GGE, Gasoline Gallon Equivalent. I've never seen GGE for battery cars, but it could be calculated, based on KWH and GGE of CNG to provide the electricity. The 99 mpg is probably a code for "No way to measure." GB Is there a KWH to GGE equivalent or conversion? It seems like an MPG conversion to KWH would not be able to account for the weight of the car.
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Post by graybeard on Nov 24, 2010 8:49:39 GMT -6
This is from the comments on the link posted by Jeffo: The EPA got 99MPGe by using the following formula: (33.7 kWh of energy per gallon of gas)/(34 kWh per 100 miles) = 99 MPGe for 73 miles Using Insideline’s numbers from their Volt review: (33.7)/(39 kWh per 100 miles) = 86 MPGe for 34 miles GarbageMotorsCo.November 23rd, 2010 at 3:21 pm Um, Government Motors already told us what the mileage was going to be? gm-volt.com/2009/08/11/chevy-volt-gets-230-mpg-city-epa-rating/230MPG Robert SchwartzNovember 24th, 2010 at 1:03 am What they are doing is equating the thermal energy in a gallon of gasoline (~130 MJ) to an amount of electricity having the same value in Joules where, by definition, 1 KWh is 3.6 MJ. The problem with that is that it is far more efficient (upwards of 99%) to convert electricity into motion by use of an electric motor than it is to convert the thermal energy in fossil fuel into motion by the use of any type of heat engine (reciprocating, turbines, etc.). The latter process is constrained by the laws of thermodynamics to mundane levels. A modern ICE does well to convert 35% of the thermal energy into motion. Fixed plants, such as those run by electric utilities, can by dint of higher capital investment, increase that level to as much as 60%. Of course most electricity is produced by the combustion of fossil fuel and the use of the thermal energy to turn generators. Therefor, ICE will always be at a disadvantage in any comparison that leaves out the original generation of the electricity. A fairer comparison would be to haircut the electricity by a factor of 50% or more to reflect that fact. If you do that to the 99 mpg given above, you get 45 mpg. Not so impressive, especially when compared to the Prius and other hybrids. ---------- Subsequent posts calculate the Leaf MPGe at 33. Without the big rebates, it would be dead in the water. Some people think fuel cell vehicles like the not yet available Honda Clarity have more potential. BTW, EPA used 12.4 cents/kwh. I pay SoCalEdison 31-35 cents/kwh. GB
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Post by waltc on Nov 24, 2010 13:31:00 GMT -6
Volkswagen is producing turbo diesel vehicles that get 50 mpg. The GM Opel/Vauxhall Tigra that does better than 60mpg on the open road or the Ford Fiesta that gets 45 mpg in the city and 60 mpg on the freeway.
But none are sold in the U.S. for various political reasons.
And oh a Citroen IMS back in 1950's got a 100 mpg. Of course something like that would never be tolerated by Americans, no DVD player, no IPOD , no heated seats or GPS, didn't need the processing power of a F-22 just to turn over the engine, etc.
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Post by graybeard on Nov 25, 2010 5:23:34 GMT -6
In 1913, a 1911 Franklin Speed Car set a certified world's economy record of 83.5 mpg. It had an aircooled 4 cyl OHV engine with spherical combustion chambers.
We've come a long way, huh?
GB
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Post by waltc on Nov 26, 2010 23:04:38 GMT -6
We've only come a long way in terms of marketing, as for vehicles we've only made real advances in comfort, safety and complexity. Basic engine mileage not so much. Though doubtless the automotive companies many Mechanical and electronic engineers with phd's working feverishly to make impractical and very expensive alternative energy vehicles that will never see the light of day. Much like the educated dolts who didn't have the sense to be embarrassed of their designs and competed in the www.theregister.co.uk/2010/09/17/automotive_x_prize/Most vehicles were mostly self propelled coffins that required a massive maintenance team to keep running and which would go airborne once they hit a nasty crosswind(such as the winner of the comp VLC)them thanks to their design. And if that's not bad enough, try stuffing a bunch of 200-300lb Americans into them and watch their tiny 40 hp motor blow.
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Post by fredorbob on Nov 27, 2010 0:07:20 GMT -6
This is from the comments on the link posted by Jeffo: The EPA got 99MPGe by using the following formula: (33.7 kWh of energy per gallon of gas)/(34 kWh per 100 miles) = 99 MPGe for 73 miles Using Insideline’s numbers from their Volt review: (33.7)/(39 kWh per 100 miles) = 86 MPGe for 34 miles GarbageMotorsCo.November 23rd, 2010 at 3:21 pm Um, Government Motors already told us what the mileage was going to be? gm-volt.com/2009/08/11/chevy-volt-gets-230-mpg-city-epa-rating/230MPG Robert SchwartzNovember 24th, 2010 at 1:03 am What they are doing is equating the thermal energy in a gallon of gasoline (~130 MJ) to an amount of electricity having the same value in Joules where, by definition, 1 KWh is 3.6 MJ. The problem with that is that it is far more efficient (upwards of 99%) to convert electricity into motion by use of an electric motor than it is to convert the thermal energy in fossil fuel into motion by the use of any type of heat engine (reciprocating, turbines, etc.). The latter process is constrained by the laws of thermodynamics to mundane levels. A modern ICE does well to convert 35% of the thermal energy into motion. Fixed plants, such as those run by electric utilities, can by dint of higher capital investment, increase that level to as much as 60%. Of course most electricity is produced by the combustion of fossil fuel and the use of the thermal energy to turn generators. Therefor, ICE will always be at a disadvantage in any comparison that leaves out the original generation of the electricity. A fairer comparison would be to haircut the electricity by a factor of 50% or more to reflect that fact. If you do that to the 99 mpg given above, you get 45 mpg. Not so impressive, especially when compared to the Prius and other hybrids. ---------- Subsequent posts calculate the Leaf MPGe at 33. Without the big rebates, it would be dead in the water. Some people think fuel cell vehicles like the not yet available Honda Clarity have more potential. BTW, EPA used 12.4 cents/kwh. I pay SoCalEdison 31-35 cents/kwh. GB Yeah it's something like this.
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Post by fredorbob on Nov 27, 2010 0:09:14 GMT -6
In 1913, a 1911 Franklin Speed Car set a certified world's economy record of 83.5 mpg. It had an aircooled 4 cyl OHV engine with spherical combustion chambers. We've come a long way, huh? GB We're been operating on WW2 technology for quite a while now, it's the limitations brought by current theoretical physics. The only thing new since WW2 is computers. Someone needs to come up with better theories on physics.
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Post by fredorbob on Nov 27, 2010 0:10:24 GMT -6
We've only come a long way in terms of marketing, as for vehicles we've only made real advances in comfort, safety and complexity. Basic engine mileage not so much.... An internal combustion engine is an internal combustion engine, there's only so many small ways you can improve on efficiency. Just like an electric motor is just an electric motor.
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Post by graybeard on Nov 27, 2010 6:30:55 GMT -6
It's not the engine/motor that's so important, but the fuel storage. A six pound gallon of gas will take a car 30-50 miles. It takes about a 500 lb battery and its physical support (frame, brakes, wheels, tires) to take that same car 30-50 miles. To refuel a battery can take all night.
Electricity/electronics has been the key to auto improvement over the last 100 years, beginning with the electric starter in 1912.
GB
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Post by fredorbob on Nov 28, 2010 1:15:43 GMT -6
Remember the "La-Ser" fad in the 1980's? Instead of spark plugs they used "La-Sers". Sounded futuristic, but it obviously didn't work out.
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nope that's my idea
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