and then found this which may work, but the benefits may not outbid the cost.
A compressed air car would generate no pollution while you are driving. However, the power plant that produces the electricity that compresses the air (or liquifies the nitrogen, for that matter) is probably generating pollution from the coal or oil it is burning. Power plants are relatively clean and very efficient compared to car engines, so this is not a bad trade-off. Still, it’s important to compare apples to apples.
Another thing that would be interesting to figure out is the efficiency of a liquid-nitrogen engine. If you burn gasoline in a car engine, only about 20 percent of it powers the wheels. The rest creates wasted heat. It would be interesting to see how efficient a power plant is, plus how efficient a nitrogen liquefier is, plus how efficient a liquid-nitrogen engine is – that would tell you whether you were creating a technology that is better or worse than the gasoline engine in terms of efficiency.
If you are wondering what the manufacturers are doing and what will happen to the large deisel engines of the not-too-distant future:-
FUTURE TRUCK POWERTRAIN CONCEPT - THE CO2 CHALLENGE
[from] Truck & Bus World Forum 8th and 9th December 2008, Gothenburg
The expected further increase of fuel prices and the CO2challenge have opened a new dimension of system cost versus efficiency.
Solutions which were not attractive in the past are gaining more and more attractiveness.
As system complexity is significantly increasing R&D strategies of OEM`s, suppliers, and engineering companies will have to be aligned in a close cooperation.
Cross functional and systems overlapping research will be mandatory.
Long term the fuel consumption of a 40 t long haul truck can be reduced by ~ 12 -23 %.
At road load approximately 1/3 is related to further development of the base engine, charging system and after-treatment systems, 1/3 can be achieved by downsizing and hybridization, and 1/3 can be achieved by using waste energy (mainly from the exhaust) by introducing a secondary / bottoming cycle.
For HD powertrains a very attractive pay back period can be expected.
It is recommendable to consider a total engine family concept, consisting e.g. of 12 ltr -8 ltr -5 ltr / 4cyl versions replacing a 16 -12 -8 ltr family.
The Volvo burns 0.7 US gallons with the aircon running, and the CAT burns 1 USG per hour at fast idle, which is 1100 rpm.
Some states have banned idling, but it gets way too hot down south not to idle, and way to cold up here not to idle. If your bunk heater has packed up, idle it. You have a great big night heater beneath you. Use it.
I would suggest that there isnt a driver with a hole in his ar*e that would sleep in a cab, freezing/sweating his nuts off when he has a
16 litre solution under the bonnet…
