First Tank of Gas, What a Ride !

Ray Moore-
Do you understand what happens when gasoline spills on the ground? Do you understand why money and effort was invested in vapor recovery gas pumps? If not, perhaps you need to do your homework on the basics of hydrocarbons and evaporation first so you might better understand the explanation. As far as the prius emissions per tank, the exact maximum allowed is 1.044g/mi (California & MA, etc. low sulfur gas at 120,000 mile lifespan from epa.gov/greenvehicles). 1.0g of this is CO. The Prius (a AT-PZEV/SULEV) has such low toxic emissions that further reductions in future cars will probably be very slight over a long time, and is given a 9.5/10 by that EPA site with 10/10 zero emissions. I read somewhere the air from the tailpipe of a PZEV is cleaner than that of a major city on a bad air day. (Can't remember the source on that, so either take it with a grain of salt or try google.com. How does that work for you?) I don't mean to frighten you, but carbon dioxide isn't actually considered toxic (I suppose it's "toxic" if it displaces oxygen for breathing, but we could say that about any substance) -- You're even breathing it right now! (I'll send you the proof in a PM if you like.. most people already accept this as fact) While CO2 may be partially responsible for the greatest environmental disaster somday, again it doesn't really make it toxic. You are right that spilled gas will have no direct or measurable effect on CO2 emissions, thought I don't think I implied that in my post. Specifically, hydrocarbon emissions are what are created in the air by spillage, and toxic runoff that can leach to waterways or ground water. I suppose to be exact the size of the drop and the amount of gas you put total in your tank may alter this pollution equation, but every time I've overpoured at the pump (in my dark rebel days) it came gushing out, not just one drop, so I will stand by my statement there will be more pollution by spilling. It is arguable whether CO air pollution or HC air/water leaching is more damaging, so I'll let you do your own research on that. EDIT: Just read on the Toyota website "In fact, driving a Prius: For 8,000 miles — about eight months of normal driving — creates less emissions than spilling a cup of gasoline" One tank approx 500miles, 1/16 of 8000 miles, cup is 8oz, 1/16 of 8oz (cup) is 0.5 oz. I can't find the precise definition of how big a drop is, but unless you are filling your tank with an eyedropper a spill will probably be 0.5oz or greater. (yes I know you get more miles out of your tank Ray by filling up until it squirts you in the eye but 500 miles/tank is a round number for the math) Website: http://129.33.47.206/about/environment/new...toyotatips.html


Topping off hurts your mileage if you spill it on the ground since it won't be burned. The actual impact depends on how much you spill and if you use the computer calculation or the pump, since the car won't calculate the gas on the ground. Basically, Gas on ground = not burned = zero MPG. Your off the cuff anecdote really doesn't prove anything in this case. If you need this explained further I'll be happy to do it in PM, but it should be just logic or common sense.

As far as the carbon canister, a common device on autos for awhile now, I'll do an empirical proof. If the system is sealed, where would liquid go in a full container when you allow for expansion (can you agree with me the gas in the ground is probably cooler than the air temp?) and motion from driving? Either to the container or breaking the seal. Granted, the canister is designed for a certain amount of liquid (thought primarily designed for vapor) since engineers are smart and know people like to try to defeat their designs, but everything has a limit. The evidence I offer of spillage are the modern cars pulling away from gas pumps dripping from their fuel ports. Thankfully, this is a fairly rare site these days since it is difficult to fill a modern cars tank completely full (those pesky engineers again!) Most people don't waste their time trying to get their tank 100% full. So I'll concede this is rare, but possible due to properties of liquids. For reference I'll let you check your Chemistry book. Most spillage would occur at the pump before the gas cap is replaced.

Wow - that certainly was a long winded version of what I tried to say earlier, with the ultimate point being, don't spill gas if you want to help the environment. Is that simple enought for you? Hopefully I was able to match your snide tone which is completely useless for a forum such as this. Generally, people can question/agree without attacking one another in a forum dedicated to knowledge. Instead, you might present proof of your own that disputes my remarks (which you did not). If you felt I was presenting non-factual information, replying with references and facts would have actually discredited my post AND been useful and helpful to everyone. If you really feel the need to flame me, just do it in a PM instead and not waste everyone else's time.

If you are criticizing me without any basis in fact, please let people know you have a need to flame rather than make a constructive, useful post.

EDIT: Added Toyota evaporative emissions source

 

It has now been proven to my satisfaction that one drop of spilled criticism can produce more than a tank's worth of pollution.