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drmiller100 · 05-31-2012, 11:57 PM

Chaz, Thank You.

I assumed the corners are rounded at the back. And I assumed 7 feet by 8 feet, for 56 square feet.
Then I went to the calculator, and typed in 15,000 pounds as vehicle weight just as a place to start.

So, I WAGged .40 for rounded corners and Cd.

I got 10.8 mpg at 60 mph, which passes a sanity test but maybe a bit high based on personal experience.

Then I typed in .177 as the 50 percent mark.

I got 16.7 mpg at 60 mph. HOLY CRAP.

So. Assume a 1000 mile trip, and assume 4 dollars per gallon.
(1000/10.8)*4 = 370 dollars without.

(1000/16.7 ) *4 = 240 dollars with.

Wow. HUGE difference!!!!

05-31-2012, 11:57 PM	#26 (permalink)
drmiller100 Master EcoModder Join Date: Dec 2011 Location: Boise Idaho Posts: 842 Thanks: 39 Thanked 89 Times in 69 Posts	Chaz, Thank You. I assumed the corners are rounded at the back. And I assumed 7 feet by 8 feet, for 56 square feet. Then I went to the calculator, and typed in 15,000 pounds as vehicle weight just as a place to start. So, I WAGged .40 for rounded corners and Cd. I got 10.8 mpg at 60 mph, which passes a sanity test but maybe a bit high based on personal experience. Then I typed in .177 as the 50 percent mark. I got 16.7 mpg at 60 mph. HOLY CRAP. So. Assume a 1000 mile trip, and assume 4 dollars per gallon. (1000/10.8)4 = 370 dollars without. (1000/16.7 ) 4 = 240 dollars with. Wow. HUGE difference!!!!