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Berkeley Engineers Have Some Bad News About Air Cars
cheeks5965 writes "We've argued before over compressed air vehicles, a.k.a. air cars. Air cars are an enchanting idea, providing mobility with zero fuel consumption or environmental impacts. The NYTimes' Green Inc. blog reports that the reality is less rosy. New research from UC Berkeley and ICF International puts a period at the end of the discussion, showing that compressed air is a very poor fuel, storing less than 1% of the energy in gasoline; air cars won't get you far, with a range of just 29 miles in typical city driving; and despite appearing green the vehicles are worse for the environment, with twice the carbon footprint as gasoline vehicles, from producing the electricity used to compress the air. Given these barriers, manufacturer claims should definitely be taken with a grain of salt."
They were first developed to be used in environments, where sparks could lead to an explosion (e.g. chemical plants or refineries). There you can't use electric cars.
>>>all those Prius owners don't really seem to care about Lithum strip mines
Prius cars don't use lithium. They use nickle and hydride, and when disposed are no more harmful than throwing-away coins and water. (Although recycling the metal would be better.)
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
I did an apprenticeship in Motor Mechanics for 4 years when I left school 25 years ago. I recall a question to the tutor back then about compressed air to drive a car. Here was his answer: Compressed air is not good as a primary driving medium, it is only good as a buffer(the storage tank) or where electricity might add risk. Examples being driving air tools in a pit below ground. By its nature, compressed air must pass thru constricted orifices. There is tremendous loss of pressure over distance. I recall our workshop compressor...very different from what you buy at a hardware store. Huge tank, dual motors, each on three phase power. The newbies job was to empty the water and oil traps from the Air Intake system. About 20 litres per day and about 200 mls of oil like fluid(The atmosphere in the workshop back then was a haze of car fumes and dust). We had 4 electric hoists and one compressed air hoist too. The air hoist could lift many times the wieght of the electric.
I think compressed air cars will serve a specialist role, operating in specific roles. Whether there is commercial visbility, I do not know. Aside from the modern buzzword of "Footprint", the technology to compress air is as old as stem and pistons. That wont change. Even on high tech air craft carriers, the landing restraints have huge hoary old compressed air pistons dampenening the jets planes. The tech below deck, keeps the ram clean and applies some lubricant periodically....just as would happen in steam train days.
In post Patriot Act America, the library books scan you.
To actually get an asynchronous motor in a car working and to control the speed you need some sophisticated electronics which weren't available when the gas pressure cars were initially developed.
The nickel mine you are thinking about is probably Inco's mine in Sudbury Ontario. There is indeed a dead zone, but it is not a strip mine, the mine is underground. The dead zone is the result of acid fallout from the smelter. After killing off the area, and facing criticism, Inco built what was then the world's largest smokestack in the early seventies. The smelter still belches sulfur compounds, but now they are dispersed over a much larger area.
Much of the area still looks like a moonscape.
http://en.wikipedia.org/wiki/Inco_Superstack
If the only tool you have is a hammer, you'd better start looking for a carpentry job.