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Environmental issues?

Posted: Tue Jan 22, 2008 5:06 am
by shud_b_rite
Is it harmful to release non-combusted greengas/propane into the atmosphere?

I know methane is bad (speeds up global warming, wont go into details), I dont know about propane however. They use it in airsoft so im assuming it isn't to harmful. Im trying to decide what the best option would be for me, propane or air. I dont care if its not illegal but if it is harmful I will try and stay away from it (i care about the environment). It is only going to be for a small marble/pellet rifle and propane seems like a good choice, but I just want to find out what effects it has, can anyone help? I have done research but this information is hard to find.

Note: I am aware that one person using propane in a small pneumatic wont destroy the world. I am also aware the propane smells and it is higly flammible. I am also aware about other gases I could use instead.

Posted: Tue Jan 22, 2008 5:58 am
by jackssmirkingrevenge
Seriously, 5 years of spudgun usage is probably less harmful than half in hour driving a car, I wouldn't be too concerned if I were you.

Posted: Tue Jan 22, 2008 6:08 am
by Infernal Maveric
If you are worried about harming the environment, then stay away from combustions. The gases are harmful, but still won't make a difference to the diminishing Ozone etc.

Go with a pnuematic and stay away from CO2, as again, that's a greenhouse gas. Use a bike pump or an air compressor and fire away. SMall BB guns can be made highly efficiant with a shock pump to get up to 400PSI of air in a chamber which out preforms combustions.

Posted: Tue Jan 22, 2008 6:34 am
by psycix
The amounts of fuel used in a spudgun are so small.
You shouldnt worry about it.

Posted: Tue Jan 22, 2008 12:57 pm
by MaxuS the 2nd
Global Warming is severely overrated.

Posted: Tue Jan 22, 2008 1:20 pm
by Fnord
If I remember right, propane is worse than chlorofluorocarbons when released into the atmosphere. However, since there are so few people doing it, you're not going to have any impact. It takes huge amounts of pollution over long time periods to effect anything.

Unless you inadvertently set off a volcano with your potato gun, you're not going to hurt the environment.

Edit: actually, after looking outside, I wouldn't mind a bit of global warming right now.

Posted: Tue Jan 22, 2008 3:19 pm
by Ragnarok
MaxuS the 2nd wrote:Global Warming is severely overrated.
It's overrated a little, but we still need to be VERY concerned about it. However, the bigger concern is that the reason it's high is the rate at which we're using the world's resources.

Unless we cut down there, in a few decades, we'll have cars and electrical gadgets that have no fuel save the small trickle we're getting from our renewable sources of both (biofuel, and solar/wind/wave/etc power).

Thing is, we're currently just disposing of the waste bits of crude oil, often by burning - we're matching supply to meet demand, rather than adapting our demands to meet supply.
Being "green" has the much more important "side-effect" that we're preserving our resources for longer.

So really, we need to stop toxifying the earth, and save it's resources.

However in this case, the difference is so tiny that you wouldn't notice it.
Actually, that's an idea... how much damage does a spudgun do to the environment?

Pneumatic and Compressor:

Some facts - one kWh of electricity from current sources is about 1 kg of CO2 (yeah, quite a lot)
But, let's say we have a cheap 1 kW compressor, which will generate 1 kg of CO2 per hour.
It outputs maybe... 3 scfm. You can get better for the same input, but this is a cheap one.
We have a 3 litre chamber at 100 psi, which needs 0.75 cubic feet to fill it. So, we get 240 fills an hour at approximately 4g of CO2 per fill.

Even the very best car (The VW Polo 1.4 TDI if you're wondering, and it trumps the Toyota Prius on both fuel efficiency and CO2 emissions) only gets about 100g of CO2 per km - so one fill of a pneumatic spudgun with a rather inefficient compressor does only as much damage to the environment as driving 130 feet in the world's most environmentally friendly car.

If you'd used CO2 bottles to fill it, it would be equivalent to a quarter mile in the car.

Propane Combustion:

I know that a molecule of methane is considered as damaging as 23 of CO2. I'm assuming propane is the same.
One firing of a 3 litre propane combustion needs 0.231 grams of propane.
If you leak all that, that's equivalent to 5.3 grams of CO2 - 175 feet in the VW Polo.

If you burn that, you will create 3 CO2 molecules - or in this case, 0.7 grams of CO2 - just 23 feet of driving.
Well, who'd of thought it? Contrary to what Infernal Maveric said, a propane combustion is actually 6 times more environmentally friendly per shot than a pneumatic using a compressor.

Summary:

But, lets put that in different terms... A hour's driving in the car at 30 mph will be about 5 kg of CO2.

That's 1250 shots of the pneumatic, and an astonishing 7150 from the propane combustion (assuming no leaked propane)
Assuming you fire on average 20 times a week - that's a year and a quarter of the pneumatic, and 6 years 11 months of the propane combustion.

If you leak every 10th shot from the combustion, that's still 4300 shots (4 years, 3 months) for the damage that one hour of driving in the world's most green car will do. Unless you have a major leak, you're very careless, or your mix is horrifically rich, it will be a lot better than that.

So, JSR was a little optimistic to say 5 years for a half hour in a car, but it was pretty close.
In short, you don't even need to be even in the slightest worried about it. If every 6 or 7 years you can cut back on your driving by an hour or two, then you've actually broken even.

So don't worry about it, spudding is a very green hobby.

PS: I'll work out later how much CO2 is generated by people using a bike pump for a fuller picture.

Posted: Tue Jan 22, 2008 3:37 pm
by Skywalker
Very good summary of our environmental/economic behavior, Rag! And nice to see some back of the envelope calculations too, that's kinda fun.

Posted: Tue Jan 22, 2008 3:51 pm
by Fnord
Of course, making a propane cylinder still produces CO2...

Posted: Tue Jan 22, 2008 5:04 pm
by psycix
Wow nice calculation Rag

Now we just need to calculate in all the gas burned to get to your PVC-store OR shipping of it AND all pollution caused by creating the PVC.
And more of that....

But if you would track down everything you use that way you will find out almost EVERYTHING pollutes.

Posted: Tue Jan 22, 2008 5:23 pm
by Ragnarok
psycix wrote:Now we just need to calculate in all the gas burned to get to your PVC-store OR shipping of it AND all pollution caused by creating the PVC.
In fairness, it's not normal to talk about the hidden CO2 costs of building the car, or getting the diesel to the fuel pumps in your local garage, etc... I don't think I need to talk about the environmental costs of creating the launchers.

But you're right. A packet of potato crisps is about 80-90g of CO2 to harvest, cook, package and transport. The planet can support some CO2 emissions, but although it would develop to handle more, we're stopping it by felling the rainforest - if we left that alone, then it would grow with the extra CO2 available, and it would simply absorb everything we make, but because most people don't give a damn, it can't.

Posted: Tue Jan 22, 2008 5:27 pm
by PVC Arsenal 17
The ocean puts out more O2 than the rainforests.

Posted: Tue Jan 22, 2008 5:51 pm
by potatoflinger
Why does everyone always talk about global warming? I think that it's just a part of the earth's natural system. Weren't people worried about global cooling 50 years ago?

Posted: Tue Jan 22, 2008 6:08 pm
by daberno123
I think that it's just a part of the earth's natural system. Weren't people worried about global cooling 50 years ago?
Yes this is how the last ice age both started and ended. Actually people are worried about how humans are impacting the earth's natural process of warming and cooling by throwing unnatural pollutants into the mix.

Posted: Tue Jan 22, 2008 6:16 pm
by shud_b_rite
For those of you who didnt know im not using it for combustion, its for a pneumatic. I also said that i am aware that one person using propane in a pneumatic is not gonna do jack to the environment even if it is harmful. I guess no one read my notes at the bottem of my first post.

I know global warming is way overrated, i dont go overboard but i try to limit the amount of harmful things that come out of my car exhaust. The reason I ask this question is because airsoft uses green gasgas (which is propane with silicon oil in it) and if it is as harmful as freon (if you know how bad it is then you'll know that its bad) then it is a big no no, even if it is used in small amounts. I have also been thinking about other ways to use this gas which would involve using it to store energy.