Direct Injection 2-Stroke Technology
The Engines and Energy Conversion Laboratory [at CSU] together with Envirofit developed a bolt-on, direct-injection retrofit kit for carbureted two-stroke engines that are major polluters in many Third World countries.
This technology drastically reduces pollution to within acceptable environmental standards while improving fuel economy more than 35 percent. This easily installed, direct-injection retrofit technology is initially targeted to the tens of millions of tricycle taxis that dominate the roads in many Third World countries.
The taxis are critical to the social structure in providing economical transportation for the working class and providing income for millions of tricycle taxi driver families. The deadly pollution from these inexpensive, yet polluting vehicles also kills thousands of people annually in areas of Southeast Asia, Africa and South America.
“Who creates gadgets to change their world?” wrote John Voelcker, author of the article that appeared in the Stanford Social Innovation Review [summer 2006 issue]. “The 10 social entrepreneurs profiled in this article do. But they don’t just invent gizmos … They also ask hard-nosed economic questions that help them understand their products’ distribution, adoption and maintenance.”
Late last year, Envirofit signed its first major agreement to retrofit 3,000 two-stroke tricycle taxi engines in Vigan, a UNESCO World Heritage city in the northern Philippines, with cleaner, more efficient engines. The innovative retrofit technology will reduce harmful emissions from two-stroke engines by up to 90 percent and reduce fuel consumption by more than 35 percent.
Economies of scale should get the cost of these units down to $200 or less. A program of micro-loans is set to operate in parallel to enable taxi operators to pay for the retrofit in one year. These dudes only make about $4-8/day.
Less pollution & better fuel economy… Nice.
Maybe Bill & Melinda can use some of Warren”s money to knock a few bucks off the price of each one. [grin]
Save a little energy and retrofit to boot? Sounds good so far.
Win-win.
But I thought pollution in the developing world was caused by Bush’s failure to sign the Kyoto Protocols?
/sarcasm
I never gave any thought to the environmental aspects when I was sneaking out of the Olongapo City hotels, as Olongapo City was off limits for overnight stays. They’d back up to the back door and we’d nip out and climb in the back, with the early morning cries of the baloot sellers following us back to the base at Subic Bay. This was back in the late sixties, and I had other things on my mind.
And what about AL ower Lawn mower/tractors???
Again, sleazy mechanics and sleazy vendors will sell/install it for an obscene price, making it a failure.
I wonder what it does for performance and horsepower..
Upping fuel economy while reducing polution? Its gotta hurt performance – force the engine to burn less gas or something – the only question is how they’d get reasonably similar power … sounds like either a hoax or something that will make the taxis near useless …
Eideard’s The Man!!
Good find amigo.
8. Its gotta hurt performance – force the engine to burn less gas or something
No, it prevents the engine from wasting as much gas… per the “Conventional Two-stroke section of the linked article:
http://www.envirofit.org/page/130/index.html
“… the exhaust ports are also open at this time, allowing 30%-40% of the fuel to be lost directly into the exhaust stream. At idle conditions the losses can be as high as 70%.”
A good animation of a conventional 2-stroke is at:
http://www.keveney.com/twostroke.html
It shows how the fuel/air circulates in the crankcase – dissolving the oil on the cylinder walls, and flushing it into the combustion chamber = burning oil…
Bruce IV –
Actually, there is a precedent for this WRT four-stroke engines – in the early 80s, when carmakers replaced carburetors and primitive emission controls (exhaust gas recirculation, etc) with catalytic converters, there were similar improvements in emissions, performance, and fuel economy simultaneously.
Nice one, Mike.
Be interesting to try. My 2 stroke fires out a lot of exhaust.. I wonder if elevation effects it any. I ride up in the mountains.. and sometimes here in the valley.. a difference of 4000-5000 feet.. it likes to foul out in the mountains. I run the fuel a bit hotter in the upper elevation.
I still think it would effect performance.
13 I still think it would effect performance.
Well, yeah…
I would expect a fuel-injected 2-stroke to out-perform a normally-aspirated one… [grin]
They don’t appear to be messing with the compression ratio, or anything like that.
The main [if not only] reasons they are getting improved economy & reduced emissions is by eliminating the waste of un-burned fuel going straight out the exhaust pipe, and by reducing the amount of crankcase oil getting into the combustion chamber.
I have a Mercury Optimax direct injection outboard. Not only does it meet US and California polution standards as if it were a 4-stroke, it gets the same mileage as the 4 strokes on similar boats.
Apparently it needs a crankshaft driven air compressor and also what looks like an electric fuel and oil pump, in addition to the doohickey that goes on the new cylinder head (does it work like a diesel with no spark?). Interesting idea, but sounds pretty expensive unless you like to tinker with and modify small engines yourself.
I wonder how those hard working low paid cab drivers will take to being told they need to put on this thing, thought up by well-meaning American college kids…
Now, what to do about all that smelly oil smoke that still comes out.
(“We can sell you a catalytic converter muffler, too…”)
Increasing efficiency in any 2-cycle engine means removing more combustion byproducts, Pterocat.
More motivating is the cost of fuel. If a taxi operator can save a couple bucks/day on fuel — when he’s making less than $10/day — is easy as pie. They won’t “need to be told” to do anything when they see other operators saving money on the cost of doing business.
If the oil flow is interrupted the motor will seize. A relative bought a $9000 outboard motor years ago and the motor blew twice because oil injection failed. If a few engines blows, these will be unbolted and dropped overboard. I hope they solved that problem, with some redundancy.
18. …and the motor blew twice because oil injection failed.
I was wondering about that.
I know some [all?] 2-strokes require oil to be mixed with the gas, while some motorcycles are designed with a separate oil tank and do the mixing automatically…
http://science.howstuffworks.com/two-stroke6.htm
Mike, virtually every 2-stroke sold in the Third World has the oil mixed into the gasoline. These folks apparently are starting with 125cc Kawasakis — the biggest chunk of what’s around — and they’re pre-mix.
I had a 2 cycle Suzuki bike once back in the 70’s, which had the separate oil injection system (no premixing the gas and oil). It metered the oil directly to the cylinder walls and presumably also to the crankcase with pipes and fittings etc. but blue smoke still emanated from it. The 2 cycle design is desirable with its light power-to-weight ratio and simplicity, but how do you lubricate it without leaking the lubricant into the exhaust?
It’s an old problem, getting rid of the junk coming out of the rear ends of cows, humans, putt-putt motors, atomic power plants etc. etc.
I wish i could get it for my bike.
The direct injection kits result in a slight increase in horsepower and better than thirty percent increase in fuel mileage, while reducing hydrocarbon emissions by 90%. They cut use of two-stroke oil by 50%. The exhaust is no longer smoky. The taxi drivers save enough on gas and oil to pay off the loan for the kit in a year or less. The World Bank estimates there are 100-million of the two-stroke taxis in Southeast Asia, contributing to brown clouds of smoke over major cities there. And NASA says those clouds regularly drift to the US. Regardless where they go, they contribute to global warming. Direct injection allows the compression ratio to be increased, creating more horsepower. The system works great in Mercury Optimax engines. Raff, the air is thinner at high altitudes. Less air means you need to reduce the amount of gas to match the air by installing leaner jets. Otherwise your bike runs rich.