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mnmarcus · 12-22-2010, 03:17 PM

Good discussion! Disclaimer: I am partial to turbodiesels and hydraulics because they are proven, reliable, "low" tech options.
Here are some links that seem relevant, please point out any errors, etc. The

faces are around my thoughts.

From Fat Knowledge: Algae Biodiesel vs. Solar Panels

The solar panel fueled electric car takes a little less that 1/5 the amount of land to run as a algae biodiesel powered car. It is by far the more efficient source of energy for sustainable transportation.

dcb, I wish it was the other way around. Might be 1/5 the cost though!?

From Electro Automotive: FAQ on Electric Car Efficiency & Pollution

Table 4. Operating Efficiency Comparison Between EVs and ICE Vehicles

EVs & Power Plants ICE & Fuel Refining
Processing 39% (Electricity Generation) 92% (Fuel Refining)
Transmission Lines 95% -
Charging 88% -
Vehicle Efficiency 88% 15%
Overall Efficiency 28% 14%

Also from Electro Automotive: FAQ on Electric Car Efficiency & Pollution

Table 5. Fuel Efficiency Comparison Between EVs and ICE Vehicles

Electric-Powered GM EV1
Start with 1 million BTUs
Energy left after generation (39% efficiency) 390,000 BTUs
Energy left after charging losses (88% efficiency) >343,000 BTUs
BTUs per kilowatt-hour 3412 BTUs
Electricity available 100.6 kWhr
Energy efficiency 0.19 kWhr/mile
Miles per million BTUs 529.5 miles
Equivalent mpg 69 mpg

Gasoline-Powered Acura .2TL
Start with >1 million BTUs
Energy left after refining (92% efficiency) 920,000 BTUs
Energy left after transport (95% efficiency) 874,000 BTUs
BTUs per gallon of gasoline 115,400 BTUs
Gallons available 7.6 gallons
Fuel economy> 24 mpg
Miles per million BTUs 182.5 miles
Equivalent mpg 24 mpg

But what is the range? I bet the Acura is farther than 182 mi & the EV isn't even close to 530mi. So I'd point out the energy density is much better with gas. If we compared the drag coefficients between these two cars the gas version would look even better, plus a turbo-diesels ICE is going to be way more efficient than a gasoline ICE...

From Electric vs Gasoline – Which is more cost effective? True Cost – Analyzing our economy, government policy, and society through the lens of cost-benefit

[1] Electrical energy is created by burning fossil fuels in a power plant at 40% efficiency, followed by transmitting it to your house at 93% efficiency, and using it in an electric vehicle at 92% efficiency, providing a total efficiency of around 34% for an electric vehicle. Crude oil refineries operate at 75% efficiency, and gasoline distribution might cause another 6% energy loss. Since internal combustion engines are only 20% efficient (gas?) , total efficiency would be around 14%. Assuming that the natural gas and oil to power our vehicles comes from the same well, we can directly compare these efficiencies, and thus conclude that electric vehicles are significantly more efficient.

So EV is .40*.93*.92=.34 efficiency
GAS is .75* .94 *.2= .20 efficiency
Would turbo-diesel be .75*.94*.41=.29 efficiency?
Does the above example skip the charging losses for the EV?
If .29*X=.34 does that mean the EV is 17% more efficient? -not including moving the batteries around?

12-22-2010, 03:17 PM	#66 (permalink)
mnmarcus EcoModding Apprentice Join Date: Feb 2010 Location: duluth mn Posts: 117 Thanks: 20 Thanked 14 Times in 10 Posts	Good discussion! Disclaimer: I am partial to turbodiesels and hydraulics because they are proven, reliable, "low" tech options. Here are some links that seem relevant, please point out any errors, etc. The faces are around my thoughts. From Fat Knowledge: Algae Biodiesel vs. Solar Panels The solar panel fueled electric car takes a little less that 1/5 the amount of land to run as a algae biodiesel powered car. It is by far the more efficient source of energy for sustainable transportation. dcb, I wish it was the other way around. Might be 1/5 the cost though!? From Electro Automotive: FAQ on Electric Car Efficiency & Pollution Table 4. Operating Efficiency Comparison Between EVs and ICE Vehicles EVs & Power Plants ICE & Fuel Refining Processing 39% (Electricity Generation) 92% (Fuel Refining) Transmission Lines 95% - Charging 88% - Vehicle Efficiency 88% 15% Overall Efficiency 28% 14% Also from Electro Automotive: FAQ on Electric Car Efficiency & Pollution Table 5. Fuel Efficiency Comparison Between EVs and ICE Vehicles Electric-Powered GM EV1 Start with 1 million BTUs Energy left after generation (39% efficiency) 390,000 BTUs Energy left after charging losses (88% efficiency) >343,000 BTUs BTUs per kilowatt-hour 3412 BTUs Electricity available 100.6 kWhr Energy efficiency 0.19 kWhr/mile Miles per million BTUs 529.5 miles Equivalent mpg 69 mpg Gasoline-Powered Acura .2TL Start with >1 million BTUs Energy left after refining (92% efficiency) 920,000 BTUs Energy left after transport (95% efficiency) 874,000 BTUs BTUs per gallon of gasoline 115,400 BTUs Gallons available 7.6 gallons Fuel economy> 24 mpg Miles per million BTUs 182.5 miles Equivalent mpg 24 mpg But what is the range? I bet the Acura is farther than 182 mi & the EV isn't even close to 530mi. So I'd point out the energy density is much better with gas. If we compared the drag coefficients between these two cars the gas version would look even better, plus a turbo-diesels ICE is going to be way more efficient than a gasoline ICE... From Electric vs Gasoline – Which is more cost effective? True Cost – Analyzing our economy, government policy, and society through the lens of cost-benefit [1] Electrical energy is created by burning fossil fuels in a power plant at 40% efficiency, followed by transmitting it to your house at 93% efficiency, and using it in an electric vehicle at 92% efficiency, providing a total efficiency of around 34% for an electric vehicle. Crude oil refineries operate at 75% efficiency, and gasoline distribution might cause another 6% energy loss. Since internal combustion engines are only 20% efficient (gas?) , total efficiency would be around 14%. Assuming that the natural gas and oil to power our vehicles comes from the same well, we can directly compare these efficiencies, and thus conclude that electric vehicles are significantly more efficient. So EV is .40.93.92=.34 efficiency GAS is .75* .94 .2= .20 efficiency Would turbo-diesel be .75.94.41=.29 efficiency? Does the above example skip the charging losses for the EV? If .29X=.34 does that mean the EV is 17% more efficient? -not including moving the batteries around?