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Edited on Mon Sep-04-06 07:51 AM by madokie
Edit to add: This is not my own writing I am only passing it on.
MPG comparisons with IC vehicles make little sense, because the energy content of a gallon of gasoline masks the HUGE wars, diplomacy, energy and other costs of gasoline. So while the gallon of gas looks like a bargain, at about 35 kWh for about 8 lbs., it comes with a "ghost" standing right behind it...dead soldiers, ruined cultures, oil-soaked Sea Otters, blasted wetlands, squandered water, electric and natural gas, air and Ocean pollution.
HOWEVER, the rule of thumb, if you want to simplify such comparisons, is that the SEV gets from 4 to 6 miles for each kWh of electric power in the battery pack. It takes a bit more energy to charge the battery, and there is a loss in inversion and re- conversion to DC charging (94.5% efficient inverter), so let's say a total "sunlight to wheel well" efficiency of 3 miles per kWh, or about 105 MPGE (105 miles traveled on the energy equivalent of one gallon of gasoline, without the gasoline).
Now let's look at the gallon of gasoline, and see what our fleet average 20 MPG *really* works out to...
More than 8% of the energy in the gallon of gasoline had to be spent for electric and natural gas to extract and refine it, according to the CEC website that making gasoline is our number one industrial user of natural gas and electric power...what do you think raises that oil from the wells, and runs the refineries? Then there is the cooling water, hundreds of millions of gallons per day of Taxpayer- subsidized potable water. So that creates a "ghost" energy that is required for that gallon, meaning it takes about 39 kWh to make the 35 kWh in the gallon of gasoline just based on traceable electric and natural gas costs. So when you burn the gallon of gas, you are burning a "ghost" 4 kWh in addition to the delivered 35 kWh, or a total of at least 40 kWh when you count in the cost of gasoline transport trucks and gas station energy usage. So that gallon of gas is already "ghosted" even ignoring pollution and land-use refinery costs in addition to extraction, pumping and refining.
Much of our war budget (can't call it defense any more) is spent on protecting and transporting oil fields and pipelines. While the energy content of running a giant aircraft carrier battle group, and its covey of warplanes, is difficult to amortize over 10B gallons of gasoline per year, we can talk about dollars...say $200B of those war dollars, meaning that each gallon of gasoline costs $20 in war costs alone. Running this down to kWh, at least 50% of the energy content in the gallon of gasoline was spent in fighting for and defending transport of that gallon of gasoline...This "ghost" energy brings us to about 80 kWh, 35 kWh delivered and at least 45 kWh "ghosts" that you can't get.
Pollution and health care costs, urban runoff of oil debris also has an energy cost...but lets be generous, and say that each gallon of gasoline has 20 kWh of these energy "ghosts" in excess of other costs.
With this kind of reasoning, tracing the life-cycle costs of gasoline, the ostensible 20 miles granted by the 35 kWh in each gallon of gasoline really costs more than 100 kWh when all upstream costs are considered.. .
The traditional calculation is that the IC vehicle gets .6 miles per kWh (20/35). But with the "ghost" energy in the calculation, the IC only gets at most .2 miles per kWh (20/100).
The additional costs of solar power...well, the sun is free, but making the solar panels costs energy. Amortized over the projected life of the solar panels, more than 25 years at 80%, these costs are very small...say 1%.
So your SEV goes 100 miles up to 200 miles on the energy equivalent of one gallon of gasoline (at between 3 and 6 miles per kWh at 35 kWh per gallon equivalent, "GGE") but at least 3 miles per GGE.
Counting in the additional energy costs of gasoline manufacture and extraction, the GGE is not 35 kWh but really 100 kWh!
So you really go the equivalent of 300 miles up to 600 miles per GGE, when the energy "ghosts" alone (not counting other costs) that come with gasoline are added in...
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