JM>  The efficiency refered to in this case is NOT just the
JM> efficiency of the engine at producing mechanical work, but
JM> rather the efficiency of the co-gen SYSTEM at producing BOTH
JM> mechanical work PLUS recoverable heat.
JM>  In a diesel, about 1/3 of the heat value in the fuel gets
JM> converted to mechanical energy (- giving the efficiency rating
JM> you are used to seeing), 1/3 of the heat value is lost in heat
JM> to the cooling system, and 1/3 of the heat normally goes out
JM> with the exhaust.
JM>  As a co-gen system, with the engine mounted in the space to
JM> be heated, all the cooling system heat is recovered and a
JM> substantial portion of the exhaust heat as well.  This gives
JM> efficiency as a co-gen system, as: 33% (mechanical energy) + 33%
JM> (heat recovered from engine cooling) + say, a 78% recovery of
JM> the heat in the exhaust - .78(.33) or 26%. SO.. as a co-gen
JM> efficiency is .33 +.33 +.26 = 93%.
 This assumes that no fuel is wasted as unburned/incompletely
burned out the tail pipe.
 * SLMR 2.1a * Is That All There Is ?
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