There are two problems with compressed air cars. First, the technology to compress air is extremely inefficient. Compressing the air heats it up, and that heat is generally lost. This represents quite a bit of lost energy in the system. Add to that the inefficiencies in whatever power system you use to power the compressor. The second problem is the reverse of the first. When the compressed air enters the cylinders and expands, the temperature drops significantly. You can use complicated multistage decompression, but that adds friction. External heating prevents the system from freezing up, but that requires energy.
IEEE Spectrum covered a prototype late last year. http://spectrum.ieee.org/energy/environment/deflating-the-air-car Ted Eckert Compliance Engineer Microsoft Corporation [email protected] The opinions expressed are my own and do not necessarily reflect those of my employer. From: John Woodgate [mailto:[email protected]] Sent: Friday, February 19, 2010 1:54 PM To: [email protected] Subject: Re: Safety requirements for schools In message <5ee25f4c3567f748871d74829b84dd9d4dd55...@tk5ex14mbxc141.redmond.corp.mic rosoft.com>, dated Fri, 19 Feb 2010, Ted Eckert <[email protected]> writes: >Hydrogen is less volatile and safer to work with than methane. Why >worry about hydrogen in cars when we have had CNG (compressed natural >gas) vehicles on the roads for years. Many of us have natural gas >piped straight into our homes. In general, hydrogen is fairly safe and >easy to work with. A British physicist has calculated that a viable car could be made to run on compressed nitrogen. If so, that would be a VERY GOOD THING. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK I should be disillusioned, but it's not worth the effort. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]> - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
