Hi, also in case others may not know: When we say ACE we mean the ACE 3000 - Russ Rollands 1984 ish dream of which the C&O almost built - then oil slid back to make coal uneconomic. The loco is essentially a diesel outline but with a fully balanced reciprocating steam engine drive, etc. – see the ultimate steam page. As such it would have an exhaust steam driven alternator thus providing the electrical power for the condenser vacuum and coolant pumps and all other auxiliaries - like the compressor, boiler feed water pumps, PF blower, cab heater and AC etc.. We would also have an auxiliary steam motor driven alternator. ETH (electric train heating - UK term)is also possible but my prototype proposal would be a freight only demonstrator, so no spare juice to keep the passengers warm - just the wee man up front.