May 20, 2007

Why can't innovation and research be emphasized on something like this?

A car that runs on compressed air (my emphasis):

Many respected engineers have been trying for years to bring a compressed air car to market, believing strongly that compressed air can power a viable "zero pollution" car. Now the first commercial compressed air car is on the verge of production and beginning to attract a lot of attention, and with a recently signed partnership with Tata, India's largest automotive manufacturer, the prospects of very cost-effective mass production are now a distinct possibility. The MiniC.A.T is a simple, light urban car, with a tubular chassis that is glued not welded and a body of fibreglass. . . .

Most importantly, it is incredibly cost-efficient to run according to the designers, it costs less than one Euro per 100Km (about a tenth that of a petrol car). Its mileage is about double that of the most advanced electric car (200 to 300 km or 10 hours of driving), a factor which makes a perfect choice in cities where the 80% of motorists drive at less than 60Km. The car has a top speed of 68 mph.

Refilling the car will, once the market develops, take place at adapted petrol stations to administer compressed air. In two or three minutes, and at a cost of approximately 1.5 Euros, the car will be ready to go another 200-300 kilometres.

As a viable alternative, the car carries a small compressor which can be connected to the mains (220V or 380V) and refill the tank in 3-4 hours.

Due to the absence of combustion and, consequently, of residues, changing the oil (1 litre of vegetable oil) is necessary only every 50,000 Km.

The temperature of the clean air expelled by the exhaust pipe is between 0 - 15 degrees below zero, which makes it suitable for use by the internal air conditioning system with no need for gases or loss of power.

This sounds ideal for huge urban areas or even fairly congested suburban areas (like north Wilmington, DE!) where one would barely even approach that top speed of 68 mph. Tom Noyes has been Delaware's information bastion about clean power, and his devotion to the topic has sparked my own interest.

Lack of serious innovation for items such as this makes me wonder sometimes if the premise for stories like this really aren't right on the money (pun intended).

Posted by Hube at May 20, 2007 08:52 AM | TrackBack

Comments  (We reserve the right to edit and/or delete any comments. If your comment is blocked or won't post, e-mail us and we'll post it for you.)

This smells like a crock to me.

Compressed air isn't a fuel, any more than batteries are a fuel. They are a storage mechanism. How does the air get compressed? Fossil fuel powered electrical compressors, certainly.

What is the secret sauce that allows one to burn gas, compress air, and then get 200 mph, when just burning gas gets only 25 mph?

I don't believe there is any.

Posted by: TJIC at May 20, 2007 10:12 AM

Hube, this sounds like an interesting approach for personal, local transportation. The plug-in electrical vehicle also comes to mind because it is similar, similar in the sense that both depend ultimately on electricity generation. Thus the cost per mile in emissions and dollars due to the generation of the electricity to run either vehicle must be taken into account when comparison is made to the internal combustion engine, also depending on what fuel is uses as well. So there is complexity here that is often glibly overlooked due to the lack of an holistic analysis. I have yet to run across an authoritative article written at this level that compares the alternatives for personal transportation.

Posted by: Perry at May 20, 2007 12:18 PM

Thanks for the interesting story (and the kind words).

Of course compressed air is a medium for storing energy rather than an energy source. I can't judge the engineering of the concept, except to note that air compressors are cheap and common. Keep us posted.

Posted by: tommywonk at May 20, 2007 09:35 PM

"What is the secret sauce that allows one to burn gas, compress air, and then get 200 mph, when just burning gas gets only 25 mph?"

It is rather simple, cars generally use piston engines running on the Otto cycle. We use these designs largely because cars start and stop a lot (in an industrial sense) so we need an engine which supplies both power and torque over a wide RPM range. Piston engines also throttle fairly well. They're also light weight and gasoline makes for a good chemical battery to store energy and give good range to the vehicle. You'll note that peak energy efficiency doesn't really factor into this anywhere.

In industrial settings, fossil fuels would probably be burned to heat water to steam which is then run through a steam turbine to produce electrical power. This equipment can be quite heavy, doesn't throttle well, and doesn't generate good power over a wide RPM band. Fortunately it doesn't need to because power levels don't generally vary widely from moment to moment over the entire grid. It is also quite a bit cleaner because you can burn the fuel at temperatures and pressures which are optimal for clean and efficient combustion. This is a very efficient system but it wouldn't make for a good car.

Posted by: Jeff the Baptist at May 21, 2007 01:53 PM