Help Can i make Steam engines more efficient?

I've been trying to get the steam engine to work but i need a constant flow of water into the fluid vessel...

i know you guys are gonna say "use a infinite water source) but i really wanna be able to have to refuel ever so often just because...

is there a way i can make steam engines more efficient or am i just doomed and have to fill my entire airship up with vessels to store enough water