Clean power system

A method of powering a diesel-fueled vehicle that meets government mandated emission limits throughout periods of varying power demand, including periods of high power demand, comprising:

• operating a diesel-fueled internal combustion engine to drive an axle and produce an exhaust comprising CO;
• processing the exhaust through a fuel cell that removes at least 50% of the CO from the exhaust and produces electric power from the exhaust;
• using the electric power to energize an electric motor that also drives the axle;
• wherein the government mandated emission limits are United States government-mandated emission limits, the meeting of which limits requires the vehicle to emit less than 0.4 g/bhp-hr NOX and less than 0.04 g/bhp-hr PM;
• throughout the periods the engine is operated in a low temperature combustion mode whereby the engine exhaust meet those limits with regard to NOX and PM emissions without exhaust aftertreatment;
• and
• the low temperature combustion mode is characterized by heterogeneous combustion of the diesel fuel with compressed air within the engine's cylinders with sufficiently large quantity of re-circulated exhaust gas such that the fuel combusts at sufficiently low temperatures that the engine produces an exhaust containing substantial quantities of hydrocarbons and CO but no more than about 0.4 g/bhp-hr NOX and no more than about 0.04 g/bhp-hr particulate matter (PM) without further treatment.