Is biodiesel more efficient than gasoline?

Question

Hi, I'm a ninth grade student and I'm doing research on biodiesel. I had to create a batch and I have to present it on a Science fair next Friday. I have some questions that need to be answered, for I have to prove a Physics principle and I need to know BIodiesel's strong points.

1) Is biodiesel more efficient than gasoline? (Can I prove it?)

2) Is biodiesel flammable?

Thank you very much

Answer 1

1 yes go to evolution bio-diesel

2 yes as much as diesel

3 yes depends on the cost of methanol and your source of veg oil ?

4 no must be diesel motor needs major rework to use in a gas motor

Answer 2

It is less efficient.  Cars get about 20% less miles per gallon and pollute about 10% more.

Yes it is flamable.

In 5-10 years Biodiesel will have been a passing fad.  It is not efficient, raises food prices, aND IS  bad for motors.

Just the current gimmick.  Farmers are the only ones benefiting

Answer 3

1. Yes bio-diesel is more efficient the gasoline, if you mean does it have more potential for work then gasoline. 1 Gallon gasoline = 124,000 Btu (rounded to nearest 1000) Bio-diesel has about 130,000 BTU/gallon diesel contains about 140,000 BTU/gallon.  It’s going to be difficult for you to PROVE bio-diesel is more efficient, gasoline and diesel engine work on different principals, so I’d download a report from the EPA showing the energy content of different fuels.

2. Bio-diesel is flammable just like diesel and burn much like diesel. That mean’s it’s harder to burn then gasoline, and thus somewhat safer then gasoline, but it also mean it will be harder to burn when give your demo. You could get an old fashion lamp, the type with a wick and burn bio-diesel that way, to show it is flammable.

Hope it helps

EDIT

Most of the people who answered are confusing ethanol with bio-diesel. Ethanol is not as efficient as gasoline or bio-diesel. Ethanol also take much more energy to create then bio-diesel, bio-diesel uses a chemical process to covert vegetable oil into fuel, while ethanol need to be distilled, using heat, to make ethanol that can be burned in a car engine.

Bio-diesel can be use in place of diesel and you don't need to start a diesel engine first before switching over to bio-diesel, you might have to do that if you use straight vegetable oil.

EDIT again

3) Is biodiesel more expensive than gasoline? It can be depending on the source of the vegetable oil, many people can get it for free, but new oil is more expensive then diesel right now, but in a few years you might see algae oil being used.

4) Can biodiesel run in a regular motor?

Bio-diesel can run in any DIESEL engine, bio-diesel is not a replacement for gasoline. As the name implies it is a replacement for diesel.

Answer 4

Quite a few views on this apparently! Bio-deiesel has a lower energy content (37 MegaJoules/Kg) than fossil diesel (42 MegaJoules/kg). However it's higher lubricity, lower cetane rating and higher oxygen content mean that engine efficiency rarely drops by more than 10%, if at all. Incidentally, this also means a more complete burn, leading to less CO2 pollution than comparative fossil diesel.

Biodiesel is not listed as a flammable liquid- FYI, it's FlashPoint is around 180C

Incidentally, the following should be taken into account when studying bio-diesel:

Bio-diesel, when well made, is good for the car and will not harm a diesel engine. However, if it is badly made (eg an incomplete catalyst reaction, a reaction left too long, using poor quality or unsuitable oils/fats in the first place) then it probably will damage the engine, or the vehicle as a whole. Possible problems are hydrogenation of the fuel (meaning water will be present in the fuel), di-glycerides or tri-glycerides being present in the fuel (leading to incomplete combustion, increased CO2, deposits left in the engine and all the other things that people believe bio-diesel will do). The key is to get the process right so that the quality of fuel can be ensured.

Incidentally, Tesco in the UK sold a batch of badly made fossil diesel a few months ago- it wrecked a few thousand vehicles. So for those out there that say "bio-diesel is flawed and destroys cars"- apparently so does fossil diesel from the pump!

Answer 5

No.  Diesel and Bio diesel get about the same mileage.  Which, in most diesels is between 8 and 12 mpg.  Were as a gasoline auto gets around 16-30 mpg.  Bio Diesel is flammable, however, you cannot start a car off of bio diesel.  A bio diesel motor requires starting with normal diesel fuel and the warming to operating temperature (which is slightly hotter with bio diesel vs normal diesel).  The great benefit of Bio Diesel, it's free (for now), made from used fry oil that can be collected from any place that has a deep fryer.

And, bio diesel does nothing to food prices, that's ethanol the other person is thinking about.

Answer 6

It takes more energy to create a gallon of biodiesel  than it can produce itself.  The only reason anyone creates the stuff is because it is subsidized by the government (which is actually our tax money).  This also makes the price of food go up and it ends up hurting poor people.

Answer 7

Biodiesel is much more efficient than gasoline.  It can drop mileage up to about 2% from diesel, but even with this drop, a VW TDI will get around 45+ mpg combined.  This is due mostly to the fact that compression ignition (diesel) engines are more efficient than spark ignition (gas) engines.  It is a fuel and thus is flammable, but won't readily burn in open air.  Trying to light a pool of it won't work, but if you soak a rag or paper towel in it, it will burn like a torch.  The flash point of biodiesel is around 266 degrees Fahrenheit, while diesel's is 147 degrees, and gasoline is -52 degrees.  It also produces less emissions than petrodiesel, even eliminating the sulfur dioxide that is a leading contributer to acid rain.

Many of the people above are talking about either straight new or waste vegetable oil or ethanol.  Vegetable oil is+ often run in dual-tank systems where the car is started and shut off on regular diesel or biodiesel.  Ethanol, the alcohol in alcoholic drinks is also used as fuel, known as E85, is used in flex-fuel vehicles, and does take almost as much if not more energy to produce as it returns.  Ethanol does have a significant loss in fuel economy when compared to gasoline, but has a higher octane rating, and can be used in high performance engines that have high compression ratios.  Also, producing the amount of ethanol required to run a car could require a lot of government paperwork and hoop-jumping since it is a controlled substance (alcoholic drinks).

Answer 8

1) Is biodiesel more efficient than gasoline? (Can I prove it?)

> VW TDI - 40 - 50 mpg

    VW gas - 20-35 mpg

epa.gov can prove it for you.

2) Is biodiesel flammable?

> No, it requires high temp. and a flame to ignite. Lighting a match will not light biodiesel (or diesel usually). This is because it has a high "Flash point", which gas does not.

3) Is biodiesel more expensive than gasoline?

> Yes. $5.00 vs $3.40 per gallon.

4) Can biodiesel run in a regular motor?

> Yes. Any regular diesel engine.