two stroke engines - engineering miracle and/or environmental abomination

[Michael D. Storey]

I do remember a dust-up here a while ago about propane fueled small outboatds. perhaps a good alternative to a two-cycle in marsh areas and small bodies of water.

[dylan winter]

what is wrong with four stroke?

sure they seldom survive being dunked.....


be careful....

don't dunk it then

what is clean water worth to you?

clearly for some poeple it counts for zip all

Dylan

[keyhavenpotterer]

Its important that when old two strokes are replaced with clean engines there not sold (to someone else to pollute the rivers with) but actively decomissioned and broken up to be unusable then the metal put in the recycle metal bin at the local tip/ recycle centre. They throw oil into the water. Water that you pull fish from, swim in and sail on. Who'd actively choose to do that to their environment, that they've gone out admire in the first place? Its an insult to the river and to others that also use it.

Dylan, chop up those seagulls and then take them to the tip. You can't sell em for spares either - just prolongs the environmental agony. You'll feel better. Less crap in your life and everyone else's given what they do. This isn't throwing away good engines, its taking the opportunity to leave your river a cleaner place before someone else gets 'em and leaves a mess for you to sail through next time your out.

[Tylerdurden]

I do remember a dust-up here a while ago about propane fueled small outboatds. perhaps a good alternative to a two-cycle in marsh areas and small bodies of water.

http://www.westmarine.com/buy/produc...ort-shaft.html

Its a great way to go for a dingy. One of the principals who developed liquid LP injection for GMC is working on it for outboards and inboards. Greater efficency and horsepower. Issue is innovation is stymied by onerous regulations and only large corporate entity's or major venture capitol can get the job done. Sad to say but the regulations everybody counts on works in reverse very often and kills development by innovators. Past that nothing is open source in the marine market place so try adapting anyone's ECU to do anything else. We shoot ourselves in the foot like this.
A good example is OBD2 and how once the architecture became open many small company's developed product's that can increase mileage and horsepower.

The whole system need to be overhauled rather than to add several new layers to it. A base line standard should be the only limit.

[wizbang 13]

When I first launched my Kutter, she had a 1957,102 seagul.As many people would admire the mill as the boat.I had a little nappy oil catcher hooked up but of course still too messy.
So,I retired it and bought a new Tohotsu.
The seagull will occoupy the "cool corner" of my storage for a long time

[dylan winter]

When I first launched my Kutter, she had a 1957,102 seagul.As many people would admire the mill as the boat.I had a little nappy oil catcher hooked up but of course still too messy.
So,I retired it and bought a new Tohotsu.
The seagull will occoupy the "cool corner" of my storage for a long time

good man

well said wizzbang

my thoughts entirely

however, some of the comments further back up the thread are bloody frightening

[sailnstink]

When I first launched my Kutter, she had a 1957,102 seagul.As many people would admire the mill as the boat.I had a little nappy oil catcher hooked up but of course still too messy.
So,I retired it and bought a new Tohotsu.
The seagull will occoupy the "cool corner" of my storage for a long time

2 or 4 stroke replacement?

[dylan winter]

excellent point there sailnstink

although just turning the seagull into a museum piece will help

I am all of a quiver to find out now

Dylan

[wizbang 13]

A 4stroke 5hp.
5 hours a gallon@ 5 knots. One ton boat

[John Bell]

Since this discussion of 2-stroke engines has veered into PWCs, there is a very real danger that we might find a solution which would lead to better PWCs, which would lead to more numerous PWCs.

But...I wonder if a 4-stroke engine with a dry-sump system would work in a PWC?

Back to 2-stroke outboards. We need to re-think the exhaust system. How about something that separates the liquids (unburned gasoline and oil) from the exhaust gases before discharging the exhaust to the atmosphere? Of course, there would need to be a reservoir to store the liquid waste for safe disposal ashore.

Tom

Um, these have been on the market for a long time. The big Yamahas are all four stroke dry sump engines. A friend has an 8 year old FX140 with a 1 liter four cyl, DOHC, 20-valve, dry sump four stroke engine making 140 HP. It's a very cool little motor. It might be fun to put one in an SCCA D-Sports Racer. It sounds fabulous revving to 10,000 rpms! I believe all the remaining two-stroke PWCs on the market are using direct injection, but I'm not positive of this fact. FWIW, Yamaha uses two of these motors in their very successful line of open bow runabouts.

I've got both two and four stroke outboards in my fleet. The 115 HP two stroke is a big gas hog, but it's damn hard to justify replacing even with marina gas around $5. A new four stroke of similar power would cost me $10K. I might get $3.5k for the old 115. I'll never burn enough gas to justify a $6500 expense. The little 6 HP four stroke is probably better but dang is it ever heavy. I hardly run either motor however. The 115 gets run long enough to get us to a favorite cove where we anchor all day before heading back the marina and the 6 hp only runs long enough to get the sailboat out to where there's enough wind to sail. And if there isn't enough wind, I don't go out to begin with.

[Mad Scientist]

Thanks, John - engine technology isn't my strong suit. Until this thread came along, the only thing I knew about dry-sump systems is that F1 cars use them...

Tom

[Jay Greer]

I have two Seagull out boards one large, one small. I do like the fact that they are a quirky reminder of earlier times. A little known fact is that they were, originaly, designed to move barges and heavy loads. The British Seagull engines, reportadly, were life savers during the evacuation at Dunkirk. Many a soldier llved to fight another day because of these reliable hi torque engines. Even so, I rarely use mine as they have an annoying habit of pissing lower case lubricant on teak decks. All in all I doubt that I have contributed a hundred billionth of a percent to world polution with them. The natural tar oozing out of undersea fishers off the California coast most likely, produces more polution in a day than all of the Seagull motors have the World over since they were first invented.
Jay

[dylan winter]

I have two Seagull out boards one large, one small. I do like the fact that they are a quirky reminder of earlier times. A little known fact is that they were, originaly, designed to move barges and heavy loads. The British Seagull engines, reportadly, were life savers during the evacuation at Dunkirk. Many a soldier llved to fight another day because of these reliable hi torque engines. Even so, I rarely use mine as they have an annoying habit of pissing lower case lubricant on teak decks. All in all I doubt that I have contributed a hundred billionth of a percent to world polution with them. The natural tar oozing out of undersea fishers off the California coast most likely, produces more polution in a day than all of the Seagull motors have the World over since they were first invented.
Jay

I agree with all you say

they are an amazing piece of engineering

they do have a wonderful history

the pollution they create is tiny compared to the natural oozes

and that final point would be relevant if we used the seagulls out at sea

but most of them are used around moorings, up creeks, on rivers and even on lakes

so one in e very five gallons you use is poured straight into the water where you sail

Imagine how you would react if you saw some bloke turn up at the ramp with a five gallon can to fill his outboard and in doing so spilled a fifth of the fuel straight into the local lake

I myself would regard him as an irresponsible twazzock


I am not saying that using an old seagull - or almost any traditional two stroke is as irresponsible as that.... but in the minds of some people it is is not that far off

In some ways seagull users are like pipe smokers - because five years ago one person complimented them on the smell of their shag they think that everyone likes the smell and are happy to light up anywhere and everywhere and sit there happily puffing indoors or out

bum.... I guess I have just upset pipe smokers and two stroke users in one post

[keyhavenpotterer]

an annoying habit of pissing lower case lubricant

They do this, oil finds it way out of every orifice additional to the cooling as you go along, leaving a slick trailing out behind you. Your not using it in the middle of the Atlantic or Pacific, your using it 100 metres out from the beach or dock to your boat in your tender. This is right where dinghy sailors, kayakers, swimmers are trying to enjoy themselves, and not get coated in oil, smell it or see it spread out accross the surface trailing out behind you. But I guess you don't see it, as your forwads of the slick. Boats are moored here too, and their owners don't want an oil slick discolouring their paintwork. Many fish feed and breed in shallow water too.

To use Seagull engines in 2012, is wholly innapropriate, ignorant, insulting to other river users and environmentally careless to the river you enjoy. Decomission and recycle it: its completely irresponsible not too. If you leave in your garage, oneday after your gone, someone will get it out, think it looks cool, all metal and shiny, and give it a run in the river. All the seals will be even more leaky, more unreliable, more and continued environmental pollution right where and when we don't need it. There not looked at with affection in the UK, just old unreliable polluting junk.

If carry weight is a problem, get some oars: ever so light and easy to carry. No back strain walking with them over the shoulder.

[Wooden Boat Fittings]

No back strain walking with them over the shoulder.

No back strain carrying a Seagull in one hand, either --

Seriously, I use my Seagull for emergency situations only, where I can't sail and where I can't row. They're amazing motors -- lightweight, powerful, and they always start on, at most, the second pull. You can store them in essentially any position. You can even drop them overboard, and they'll still start again after a quick clean.

In fact, I'm in agreement in principle with Dylan's thesis (and even though I smoked a pipe for forty-odd years,) but the amount of pollution my Seagull has contributed to the environment over its quarter-century lifetime has, I'm sure, been considerably less than that contributed by the average Forum member's motor vehicle over the last six months.

And the amount of pollution required to produce any four-stroke replacement for my Seagull would be measured in multiples of several hundred.

So, no, I'm afraid it's not going to landfill just yet.

Mike
Edited to add -- Dylan, tt wasn't shag, but Erinmore Flake.

[Ian McColgin]

About ten years ago a naval engineer and boatbuilder named Andre Mele wrote "Polluting for Pleasure." Sadly, it's not out of date.

[Bill Huson]

seems like someone (chemist) could come up with a soy or corn based oil for 2 strokes that wouldn't be nearly as bad.

Best solution = methanol and castor oil. Works great! Tad difficult to fire up, might have to squirt gasoline in the carb to get her going, but then engine will run like a screaming b---h!

[Ian McColgin]

One of the points overlooked by even "environmentally concerned" piston heads is the simple physical damage done by propellers, especially small high RPM props as found in pleasure boats. Sometime take some surface water samples in a productive wetland and study them under a low power (50x or so) mic. Then compare a surface water sample from the same place but in an outboard's wake. You'll be stunned at the carnage. Good wetlands are so productive and the damage is so concentrated at the small invertebrate level that we ignore it, but the cumulative loss of bioproductivity is a national disgrace.

[carioca1232001]

Why 2-Stroke Direct Injection is a Big Deal

I learnt about the break-through development in 2-stroke technology - most of it at Bombardier´s initiative - from a friend at my yacht club.

He has just bought himself a 24' fishing boat powered by a Mercury outboard and said he would have much preferred one of the current Evinrudes, which is how the subject came to my attention (Have been partial towards 2-strokes due to the offensive exhaust fumes).

Thanks for the link.

[Woxbox]

These look interesting. Propane powered outboards.

[Canoeyawl]

so one in e very five gallons you use is poured straight into the water where you sail

I doubt this...
edit to add, five gallons of gas in my seagull is about one hundred years.

[St.J]

I remember my boating childhood through a cloud of 2 stroke smoke.
We had two Seagulls and used them on the extraordinary number of small boats that passed through my family. Boats came and went but my father still has the Seagulls in his shed. The damn things never die. Though from the noise you'd think they were on the brink of it all the time.
Whether you're worried about their impact on the environment or not (and pouring 2 stroke oil into the Blackwater and watching it slop back and forth over an oyster bed worried me) it's their impact on the environment around my head that bothers me the most. Noisy and smelly and not conducive to a relaxing time on the water.
I've just replaced my ageing 2 stroke with a smaller 4 stroke and when we ran them side-by-side in the tank at the shop I was stunned by the difference in volume.
My father, however, replaced the Seagulls with a Torqeedo.
No competition.
When they make them more powerful and with a longer range I'll get one.

I like my boating peaceful and unhampered by obvious stimuli for guilt.


St.John

[Canoeyawl]

I'm not convinced that Batteries are any better. That we cannot see the results of the pollution caused by the manufacturing and disposal, does not make it less of a problem.
The damage to environment is perhaps not as obvious (yet). But the introduction of roughly 50,000 tons of lead each year into the landfill cannot be good.

wiki

According to a 2003 report entitled, "Getting the Lead Out," by Environmental Defense and the Ecology Center of Ann Arbor, Mich., the batteries of vehicles on the road contained an estimated 2,600,000 metric tons (2,600,000 long tons; 2,900,000 short tons) of lead. Some lead compounds are extremely toxic. Long-term exposure to even tiny amounts of these compounds can cause brain and kidney damage, hearing impairment, and learning problems in children.^[16] The auto industry uses over 1,000,000 metric tons (980,000 long tons; 1,100,000 short tons) every year, with 90% going to conventional lead-acid vehicle batteries. While lead recycling is a well-established industry, more than 40,000 metric tons (39,000 long tons; 44,000 short tons) ends up in landfills every year. According to the federal Toxic Release Inventory, another 70,000 metric tons (69,000 long tons; 77,000 short tons) are released in the lead mining and manufacturing process.^[17]
Attempts are being made to develop alternatives (particularly for automotive use) because of concerns about the environmental consequences of improper disposal and of lead smelting operations, among other reasons. Alternatives are unlikely to displace them for applications such as engine starting or backup power systems, since the batteries are low-cost although heavy.

[seedy]

One of the points overlooked by even "environmentally concerned" piston heads is the simple physical damage done by propellers, especially small high RPM props as found in pleasure boats. Sometime take some surface water samples in a productive wetland and study them under a low power (50x or so) mic. Then compare a surface water sample from the same place but in an outboard's wake. You'll be stunned at the carnage. Good wetlands are so productive and the damage is so concentrated at the small invertebrate level that we ignore it, but the cumulative loss of bioproductivity is a national disgrace.

I remember taking "the cat" from Yarmouth, seeing a large area around it turned to roiling bubbles by the jets as it pulled out, wondering about how much damage it was causing. There is no way to have a completely neutral effect on our environment, but seeing the comments here gives me some hope that we'll work it out and do better. Not perfect, but better.

My 70's motorcycle probably pollutes more just sitting there than my newer car does driving. It's getting better, took a lot of bickering and persistence to overcome the corporate heel-dragging, but we're making headway. Every change we make for cleaner air and water benefits everyone, whether they subscribe or not.

[62816inBerlin]

While 2-strokes are not banned in Berlin/Brandenburg waterways, the water quality has still improved immensely due to reduced industrial pollution, phosphate elimination and the like. All operators of 2-stroke equipment (from outboards right down to those horrible leaf-blower thingys) are requested to use special biodegradable oils.
Personally I use a 2 1/2 HP Tohatsu to get around on windless days and to my dock in unfavourable conditions. Consuming less than 10 litres per annum and a 30:1 or 40:1 mix, I do not have a bad conscience about using the 2-stroke. Every day in the summer, the excursion "steamers" passing by belch diesel fumes and often leaving traces of oil seem to indicate that other issues need to be tackled.
Although I am an environmentalist at heart, I am of the opinion that humans, too, are part of the environment and have the right to use resources, even for pure enjoyment, as long as we do it in a responsible, conservative fashion. Posing restrictions that are too tight gets peoples' backs up and encourages a back-swing, leading to support for those who want to deregulate everything.

Cheers!
Gernot H.

[John Bell]

If carry weight is a problem, get some oars: ever so light and easy to carry. No back strain walking with them over the shoulder.

I've got oars in my boat also. The problem is my boat rows like it's a sailboat. That is to say not very well. It's just nice to be able to motor a mile and a half out of the narrow cove where my usual boat ramp is located to the best sailing area on the the lake. I'll take a bit of back strain to save me from having to row a cranky sailboat a couple of miles.

[wizbang 13]

I motor my " Kutter" for 60 miles,one way ( gig harbor to port Townsend)or a50 mile round trip ( gig to oly n back) witthout a second thought. No torquedo can do that .

[Mad Scientist]

I'm not convinced that Batteries are any better. That we cannot see the results of the pollution caused by the manufacturing and disposal, does not make it less of a problem.
The damage to environment is perhaps not as obvious (yet). But the introduction of roughly 50,000 tons of lead each year into the landfill cannot be good...

I suspect that the pollution from lead batteries in landfills is several orders of magnitude less than the polution from tetra-ethyl (sp?) lead which was used in gasoline back in the bad old days.

It seems to be in the nature of batteries to require highly reactive (and usually toxic) chemical combinations to achieve usable energy densities. (But I sure wouldn't mind being wrong about this!)

Tom

[Canoeyawl]

I suspect that the pollution from lead batteries in landfills is several orders of magnitude less than the polution from tetra-ethyl (sp?) lead which was used in gasoline back in the bad old days.
Tom

That is a given. (There are other evils associated with energy and resources. War being one of them).
There was an interesting theory that violent crime has been significantly reduced since the elimination of lead from gasoline.

"Tests have shown that the amount of lead in Americans’ blood fell by four-fifths between 1975 and 1991. A 2007 study by the economist Jessica Wolpaw Reyes contended that the reduction in gasoline lead produced more than half of the decline in violent crime during the 1990s in the U.S. and might bring about greater declines in the future. Another economist, Rick Nevin, has made the same argument for other nations."

link

[62816inBerlin]

Re: Batteries
Lead or other batteries should be fully recyclable as they are compact encased units.
Here in Germany you either have to return an old battery when purchasing a new one or you have to pay a deposit. This means the old batteries are sent to recycling companies for recovery of the raw materials.
Re: 2 strokes and fuels
As someone commented earlier - possibly the environmental damage associated with the production of a new engine, however clean, outweighs the damage caused by keeping and running an old engine for 10 - 20 hours a year. Of course the damage occurs elsewhere, not on your favourite pond, but to mother Earth, it's all the same.
We never used leaded gas - the tetraethyl lead is only required for the valves of 4-strokes. In Trinidad, unleaded gas was sold for cooking purposes and (I believe) taxed lower than motor fuel, so using it made economical sense although no one even thought about the ecological aspect in the 1960s!

Whether I'd use an engine at all depends on the size of the body of water and the conditions. I've never used one on my Mirror. Occasionally go motoring around the lake with the frozen-snot daysailer on windless days and have no qualms about that.

Gernot H.

[Ted Chism]

I've got a low hours Vire 7 that I am planning to instal in my current build. So, how enviromentaly nasty is an engine like this? Am I going to be embarased by the oil slik in my wake, or am I going to be able motor with a relatively "clean" conscience?

[Canoeyawl]

I've got a low hours Vire 7 that I am planning to instal in my current build. So, how enviromentaly nasty is an engine like this? Am I going to be embarased by the oil slik in my wake, or am I going to be able motor with a relatively "clean" conscience?

It will be horrible, a nightmare... Just send it to me today and I'll recycle it for you.

[PeterSibley]

This seems a possible solution, one I'm going to investigate.

[Ron Williamson]

That is a given. (There are other evils associated with energy and resources. War being one of them).
There was an interesting theory that violent crime has been significantly reduced since the elimination of lead from gasoline.

"Tests have shown that the amount of lead in Americans’ blood fell by four-fifths between 1975 and 1991. A 2007 study by the economist Jessica Wolpaw Reyes contended that the reduction in gasoline lead produced more than half of the decline in violent crime during the 1990s in the U.S. and might bring about greater declines in the future. Another economist, Rick Nevin, has made the same argument for other nations."

link

I recently heard a bit on the radio regarding the drop in violent crime.
They attributed some of it to the increase in the availability of birth control in the sixties and seventies.
R

[Hwyl]

I recently heard a bit on the radio regarding the drop in violent crime.
They attributed some of it to the increase in the availability of birth control in the sixties and seventies.
R

TThat is proposed in the book Freakonomics.

I'd hoped this thread would have brought out some of the ground breaking designs in 2 strokes, there is an Australianone that works with flitch plates and many small cylinders

[P.I. Stazzer-Newt]

There are more things in heaven and earth.....

Enter, stage left, the ghosts of Favill and Hooper.

Google and the two-stroke time machine

[upchurchmr]

Boy you got me there. I immediately went looking for Australianone to see what was new. Finally realized you needed a space. I had kept reading this thread in hopes there would be something new that could work and not offend the nazi's (ECO). While I do agree there is a problem, some of the attitudes seam more like religous zealotry than anything else.

I would appreciate if you could include a link if you have some actual information to bring to our attention. Thanks

Australianone[/COLOR] that works with flitch plates and many small cylinders

[zertgold]

I haven't read this whole thread, but wanted to leave my two cents. 2-cycle has advantages over 4, but it is destructive to the environment. I think a couple submissions have touched on this; I was talking to a older man at the yard. He said a long time ago he was helping this kid with an dirt bike engine, two-stroke. The kid said something was wrong so the guy took the whole engine a part. The engine was unique as there was a separate reservoir for the oil. The old man put the engine back together cleaning up a few things, but finding nothing wrong. He started it up and it ran fine.

He had one question for the kid though: "What was all the white stuff in the engine? I have never seen anything like it."
The kid says: "its milk. I ran out of oil and noticed milk was slippery" (I assume farm milk)

The old man was baffled, but the milk seemed to be doing the trick. Makes you wonder what environmentally friendly things you could use in a two cycle engine. Fish oil? Snake oil?

[Phil Y]

Dylan mate comparing the old Seagull to a modern 2 stroke is a bit of a long bow. The real thrust in those Seagulls is the same as those soap boats you made in the bath when you were a kid, something to do with surface tension-the slick of oil actually pushes the boat into the clean water in front. The prop is more or less superfluous-thats why they mostly don't bother with clutches, and of course reverse gear wouldn't work. Modern 2 strokes don't drip fuel into the water, and they actually burn the oil-I mix mine about 50 to 1 and that seems fine. Someone above suggested that EPA says 2 stroke outboards account for most of the marine pollution on the planet-or something like that. Sorry I just can't believe that. Particularly in the UK where there are still plenty of old Jaguars about, most marine oil pollution would surely come from stormwater run-off.

[DanSkorupka]

I have a bit of expertise in this area.

Whether a two stroke is dirty or not depends mostly on if it is taken proper care of.

I have seen pre ww1 era evinrude RBM motors chugging along on 16/1 mix using 3 weight 4 stroke oil and running like a top with no smoke whatsoever. I have also seen high strung 100/1 mix yamaha loopers in every condition from almost 4 stroke cleanliness to toxic purple cloud.
I have owned a crossflow 2 stroke evinrude and that one motor has been in every shape from "visible oil slick when moving on a boat" all the way to "barely can smell the fumes when running in a bucket"

I will admit that other than without fuel injection or strato charging twostrokes will never have good values for HC output, but the level of pollution depends on the user, and the condition of the engine and most importantly NEEDS NOT BE TERRIBLE.
I have seen seagulls running cleaner than the little tohatsu loopers do when freshly broken in. It is not magic.
A properly tuned two stroke will burn the lubricant so much cleaner and hotter than the petrol that you can get a boost of over a hp on a motorcycle by using 16 to 1 instead of the recommended 32/1. The engine in that study was unharmed by an 80/1 torture test so reduced friction is a small player. There was only a tiny increase in carbon buildup from the 60/1 run and the 16/1 run. The tests were performed with non synthetic conventional oil in the 1970s

[John Bell]

Dylan mate comparing the old Seagull to a modern 2 stroke is a bit of a long bow. The real thrust in those Seagulls is the same as those soap boats you made in the bath when you were a kid, something to do with surface tension-the slick of oil actually pushes the boat into the clean water in front. The prop is more or less superfluous-thats why they mostly don't bother with clutches, and of course reverse gear wouldn't work. Modern 2 strokes don't drip fuel into the water, and they actually burn the oil-I mix mine about 50 to 1 and that seems fine. Someone above suggested that EPA says 2 stroke outboards account for most of the marine pollution on the planet-or something like that. Sorry I just can't believe that. Particularly in the UK where there are still plenty of old Jaguars about, most marine oil pollution would surely come from stormwater run-off.

Golf clap!

[AnalogKid]

Boy you got me there. I immediately went looking for Australianone to see what was new. Finally realized you needed a space. I had kept reading this thread in hopes there would be something new that could work and not offend the nazi's (ECO). While I do agree there is a problem, some of the attitudes seam more like religous zealotry than anything else.

I would appreciate if you could include a link if you have some actual information to bring to our attention. Thanks

This is the only Australian engine I know of (not saying much) that uses flitch plates. It's not a gasoline engine but runs on compressed air. For small utility vehicles, scooters, for lifts and possibly small outboards it looks really promising, but I've been watching it for years and there have been disappointingly few developments of late.

[upchurchmr]

I don't know what a flitch plate, but this kind of motor (compressed air) has been debunked time and time again. Not enough energy in compressed air to do much, especially for a trip. These guys act like compressed air is free. Sitting at home doing nothing will be good for pollution, and that's what you will be doing if you have one of these.

[AnalogKid]

Well apparently the engines have been fitted to the little trucks in Melbourne market for years now - perhaps one of our Melbourne based correspondents could comment. It's never going to power a full sized pickup at interstate speeds for 200 miles, but what engineair have to date looks viable for personal urban transport.

And where does it suggest the compressed air magically appears? The site advocates heat recovery systems linked to high efficiency compressors and distribution sites. Pretty much all alternative energy solutions are about moving the point of pollution from a low-efficiency distributed model to a more central point where emissions can be better managed. Also, if that point source involves generating electricity then zero emission solutions could apply (hydro, geo-thermal, wind farm, etc.).

[upchurchmr]

I would really like to see some actual numbers. How big of a tank is required for 20 miles? Or what ever. How much does a charge cost? High efficiency compressors and distribution sites don't exist, as far as I know. What are you going to due with the recovered heat? If you don't have a direct and immediate useage this is just wasted energy. This is pie in the sky, suitable for very local use, since you have to get home or get a tow. I can see it inside a manufacturing plant, but it is going to cost. Does anybody know what pressure the tanks run at? Perhaps we should ask a scuba shop what it actually costs to fill a tank. What is the equivalent $/gallon energy compared to gasoline?

[62816inBerlin]

I have seen the size of a compressed-air tank that is only used to re-start a slow-running reversible diesel engine (installed in 1967 in a former steamboat) directly coupled to the prop shaft. That is an impressive amount of steel. To store enough energy in compressed air to travel any distance in a reasonably-sized vehicle you either need a humongous tank (volume wise) containing lower pressure air or a very strong, heavy tank at extremely high pressure.
It would be interesting to compare the energy/weight and energy/volume ratios of this form of storage to that of accumulator batteries (lead/acid, lithium ion, NiCad) and supercapacitors.
Anyone care to research the issue ?

Gernot H.

... the difference between men and boys is the price of their toys ...

[Phil Y]

Is that like a steam engine, but using compressed air instead of generated steam?

[Stiletto]

Is that like a steam engine, but using compressed air instead of generated steam?

Snap!
I was going to say that it looked like steam could be used to power it.

[62816inBerlin]

Snap!
I was going to say that it looked like steam could be used to power it.

Like this ?


or this

http://www.flickr.com/photos/benfran...5835/lightbox/

or this ?


... the difference between men and boys is the price of their toys ...
Gernot H.