BioDiesel Benz on "MythBusters"

Cool! I just Tivo'd it... can't wait to watch it.

This is commonly done in the UK. Sometimes people add thinners to the vegetable oil.

DRAT! Why can't the gas engines run on E85 gas???? Guess I will have to consider a diesel if I want to buy another MB.

The MB petrol engines should run on Ethanol but they might need adjustment. Some cars produce more power on Ethanol. Ethanol is getting more common in the UK as is LPG.

My feeling is that if Ethanol takes off, countries that are very fertile and able to produce the sugar beet used in ethanol production will become the new OPEC.

Ethanol is caustic. E85 (85% ethanol, 15% petrol) requires fuel supply components that will not degrade when they come in contact with ethanol in this high of a concentration. Most vehicles in the US cannot handle E85 unless they are marked as FFV (Flex Fuel Vehicle) and these were mainly produced as a tax dodge by the auto makers (I believe that there was some incentive that so many vehicles had to support alternative fuels). But note that the MPG you get from E85 is measurably less than pure petroleum, so the true savings may be minor, if not negative. E10 (10% ethanol) is safe for most all cars and has been common in many areas of the US for a long time.

Josh

Indeed. In the Uk some petrol companies water down the petrol with ethanol. As much as 15%. You get noticeably fewer MPG especially in cars with bigger engines.

Who told you that? One gallon of ethanol = about 80,000 BTU One gallon of gasoline = about 115,000 BTU

So there is less energy in a gallon of ethanol than in a gallon of gasoline.

If the ethanol has less energy then how in the heck are you going to get more energy out of the fuel?

Older engines that are not designed for ethanol will not run right... thereby weaker. Engines that are designed for FFV will utilize ethanol more efficient and thereby more power.

Easy, Ethanol has far a higher octane rating than gasoline, so you can use a much higher compression ratio. Either through a higher static ratio or turbo/supercharging. Saab sells their BIOPower turbo in Europe that gets 184hp out of a 2.0l 4 cylinder turbo when running on E85, but only 148 on straight gasoline. However, I have seen no fuel consumption figures for that engine for each mode, I can only assume that it is considerably worse on E85.

Kevin Rhodes Westbrook, Maine, USA

Better (more complete) combustion for one I would think. Also the temperature difference; ie exhaust temperature could make a difference. Probably more factors...

cheers, guenter

possibility of running a Diesel auto on french fry grease.

Their viewers must be pretty ignorant if this is Discovery worthy news to them.

cp